feat: add CI for docker

Docker and Compose support is provided through a standalone repo at
https://github.com/chatmail/docker, add reusable Docker build/test CI
jobs to staging workflows and a Docker docs stub pointing to the
chatmail/docker repository.

Requires CHATMAIL_DOCKER_DISPATCH_TOKEN secret in relay repo settings
(fine-grained PAT with contents:write on chatmail/docker).

.github/workflows/ci.yaml

@@ -15,7 +15,7 @@ jobs:
         with:
           ref: ${{ github.event.pull_request.head.sha }}
       - name: download filtermail
-        run: curl -L https://github.com/chatmail/filtermail/releases/download/v0.5.2/filtermail-x86_64 -o /usr/local/bin/filtermail && chmod +x /usr/local/bin/filtermail
+        run: curl -L https://github.com/chatmail/filtermail/releases/download/v0.6.1/filtermail-x86_64 -o /usr/local/bin/filtermail && chmod +x /usr/local/bin/filtermail
       - name: run chatmaild tests 
         working-directory: chatmaild
         run: pipx run tox

.github/workflows/docker-deploy.yaml

@@ -0,0 +1,125 @@
+name: Docker deploy
+
+on:
+  workflow_call:
+    inputs:
+      staging_host:
+        required: true
+        type: string
+        description: 'SSH hostname (e.g. staging2.testrun.org)'
+      mail_domain:
+        required: true
+        type: string
+        description: 'MAIL_DOMAIN for docker compose'
+      zone_file:
+        required: true
+        type: string
+        description: 'Default zone file basename (e.g. staging.testrun.org-default.zone)'
+
+jobs:
+  deploy-docker:
+    name: Docker deploy on ${{ inputs.staging_host }}
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    environment:
+      name: ${{ inputs.staging_host }}
+      url: https://${{ inputs.staging_host }}/
+    concurrency: ${{ inputs.staging_host }}
+    env:
+      VPS: root@${{ inputs.staging_host }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: true
+      - name: Setup SSH
+        run: |
+          mkdir ~/.ssh
+          echo "${{ secrets.STAGING_SSH_KEY }}" >> ~/.ssh/id_ed25519
+          chmod 600 ~/.ssh/id_ed25519
+          ssh-keyscan ${{ inputs.staging_host }} > ~/.ssh/known_hosts
+          # Reuse TCP connection for all subsequent ssh/scp calls
+          echo -e "Host ${{ inputs.staging_host }}\n  ControlMaster auto\n  ControlPath ~/.ssh/ctrl-%r@%h:%p\n  ControlPersist 10m" >> ~/.ssh/config
+
+      - name: stop bare services, install Docker, prepare mounts
+        run: |
+          ssh $VPS bash -s <<'EOF'
+          systemctl stop postfix dovecot nginx opendkim unbound filtermail doveauth chatmail-metadata iroh-relay mtail fcgiwrap acmetool 2>/dev/null || true
+          curl -fsSL https://download.docker.com/linux/debian/gpg -o /etc/apt/keyrings/docker.asc && chmod a+r /etc/apt/keyrings/docker.asc
+          echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/debian $(. /etc/os-release && echo $VERSION_CODENAME) stable" > /etc/apt/sources.list.d/docker.list
+          apt-get update
+          apt-get install -y docker-ce docker-ce-cli containerd.io docker-compose-plugin
+          mkdir -p /srv/chatmail/certs /srv/chatmail/dkim
+          cp -a /var/lib/acme/. /srv/chatmail/certs/ || true
+          cp -a /etc/dkimkeys/. /srv/chatmail/dkim/ || true
+          cp /etc/chatmail/chatmail.ini /srv/chatmail/chatmail.ini
+          EOF
+
+      - name: deploy with Docker
+        run: |
+          SHORT_SHA=$(echo "${{ github.sha }}" | cut -c1-7)
+          GHCR_IMAGE="ghcr.io/chatmail/docker:sha-${SHORT_SHA}"
+          rsync -avz --exclude='.git' --exclude='venv' --exclude='__pycache__' ./ $VPS:/srv/chatmail/relay/
+          echo "${{ secrets.GITHUB_TOKEN }}" | ssh $VPS "docker login ghcr.io -u ${{ github.actor }} --password-stdin && \
+            docker pull ${GHCR_IMAGE} && \
+            cd /srv/chatmail/relay && CHATMAIL_IMAGE=${GHCR_IMAGE} MAIL_DOMAIN=${{ inputs.mail_domain }} docker compose -f docker/docker-compose.yaml -f docker/docker-compose.ci.yaml up -d"
+
+      - name: wait for container healthy
+        run: |
+          ssh $VPS 'docker exec chatmail journalctl -f --no-pager' &
+          LOG_PID=$!
+          trap "kill $LOG_PID 2>/dev/null || true" EXIT
+          for i in $(seq 1 60); do
+            status=$(ssh $VPS 'docker inspect --format={{.State.Health.Status}} chatmail 2>/dev/null' || echo "missing")
+            echo "  [$i/60] status=$status"
+            if [ "$status" = "healthy" ]; then
+              echo "Container is healthy."
+              exit 0
+            fi
+            if [ "$status" = "unhealthy" ]; then
+              echo "Container is unhealthy!"
+              break
+            fi
+            sleep 5
+          done
+          echo "Container did not become healthy."
+          kill $LOG_PID 2>/dev/null || true
+          ssh $VPS bash -s <<'EOF'
+          echo "--- failed units ---"
+          docker exec chatmail systemctl --failed --no-pager || true
+          echo "--- service logs ---"
+          docker exec chatmail journalctl -u dovecot -u postfix -u nginx -u unbound --no-pager -n 50 || true
+          echo "--- listening ports ---"
+          docker exec chatmail ss -tlnp || true
+          echo "--- chatmail.ini ---"
+          docker exec chatmail cat /etc/chatmail/chatmail.ini || true
+          EOF
+          exit 1
+
+      - name: show container state
+        run: |
+          ssh $VPS bash -s <<'EOF'
+          echo "--- listening ports ---"
+          docker exec chatmail ss -tlnp
+          echo "--- chatmail.ini ---"
+          docker exec chatmail cat /etc/chatmail/chatmail.ini
+          EOF
+
+      - name: Docker integration tests
+        run: ssh $VPS 'docker exec chatmail cmdeploy test --slow --ssh-host @local'
+
+      - name: Docker DNS
+        run: |
+          git checkout .github/workflows/${{ inputs.zone_file }}
+          ssh $VPS bash -s <<'EOF'
+          docker exec chatmail chown opendkim:opendkim -R /etc/dkimkeys
+          docker exec chatmail cmdeploy dns --ssh-host @local --zonefile /opt/chatmail/staging.zone --verbose
+          docker cp chatmail:/opt/chatmail/staging.zone /tmp/staging.zone
+          EOF
+          scp $VPS:/tmp/staging.zone staging-generated.zone
+          cat staging-generated.zone >> .github/workflows/${{ inputs.zone_file }}
+          cat .github/workflows/${{ inputs.zone_file }}
+          scp .github/workflows/${{ inputs.zone_file }} root@ns.testrun.org:/etc/nsd/${{ inputs.staging_host }}.zone
+          ssh root@ns.testrun.org "nsd-checkzone ${{ inputs.staging_host }} /etc/nsd/${{ inputs.staging_host }}.zone && systemctl reload nsd"
+
+      - name: Docker final DNS check
+        run: ssh $VPS 'docker exec chatmail cmdeploy dns -v --ssh-host @local'

.github/workflows/test-and-deploy-ipv4only.yaml

@@ -4,6 +4,7 @@ on:
   push:
     branches:
       - main
+      - j4n/docker-pr
   pull_request:
     paths-ignore:
       - 'scripts/**'
@@ -12,6 +13,11 @@ on:
       - 'LICENSE'
 
 jobs:
+  trigger-docker-build:
+    if: github.event_name == 'push'
+    uses: ./.github/workflows/trigger-docker-build.yaml
+    secrets: inherit
+
   deploy:
     name: deploy on staging-ipv4.testrun.org, and run tests
     runs-on: ubuntu-latest
@@ -22,6 +28,8 @@ jobs:
     concurrency: staging-ipv4.testrun.org
     steps:
       - uses: actions/checkout@v4
+        with:
+          submodules: true
 
       - name: prepare SSH
         run: |
@@ -63,13 +71,13 @@ jobs:
           # download acme & dkim state from ns.testrun.org
           rsync -e "ssh -o StrictHostKeyChecking=accept-new" -avz root@ns.testrun.org:/tmp/acme-ipv4/acme acme-restore || true
           rsync -avz root@ns.testrun.org:/tmp/dkimkeys-ipv4/dkimkeys dkimkeys-restore || true
-          # restore acme & dkim state to staging2.testrun.org
+          # restore acme & dkim state to staging-ipv4.testrun.org
           rsync -avz acme-restore/acme root@staging-ipv4.testrun.org:/var/lib/ || true
           rsync -avz dkimkeys-restore/dkimkeys root@staging-ipv4.testrun.org:/etc/ || true
           ssh -o StrictHostKeyChecking=accept-new -v root@staging-ipv4.testrun.org chown root:root -R /var/lib/acme || true
 
-      - name: run deploy-chatmail offline tests 
-        run: pytest --pyargs cmdeploy 
+      - name: run deploy-chatmail offline tests
+        run: pytest --pyargs cmdeploy
 
       - name: setup dependencies
         run: |
@@ -102,3 +110,12 @@ jobs:
       - name: cmdeploy dns
         run: ssh root@staging-ipv4.testrun.org "cd relay && scripts/cmdeploy dns -v --ssh-host localhost"
 
+  deploy-docker:
+    needs: [deploy, trigger-docker-build]
+    if: github.event_name == 'push'
+    uses: ./.github/workflows/docker-deploy.yaml
+    with:
+      staging_host: staging-ipv4.testrun.org
+      mail_domain: staging-ipv4.testrun.org
+      zone_file: staging-ipv4.testrun.org-default.zone
+    secrets: inherit

.github/workflows/test-and-deploy.yaml

@@ -4,6 +4,7 @@ on:
   push:
     branches:
       - main
+      - j4n/docker-pr
   pull_request:
     paths-ignore:
       - 'scripts/**'
@@ -12,6 +13,11 @@ on:
       - 'LICENSE'
 
 jobs:
+  trigger-docker-build:
+    if: github.event_name == 'push'
+    uses: ./.github/workflows/trigger-docker-build.yaml
+    secrets: inherit
+
   deploy:
     name: deploy on staging2.testrun.org, and run tests
     runs-on: ubuntu-latest
@@ -95,3 +101,12 @@ jobs:
       - name: cmdeploy dns
         run: cmdeploy dns -v
 
+  deploy-docker:
+    needs: [deploy, trigger-docker-build]
+    if: github.event_name == 'push'
+    uses: ./.github/workflows/docker-deploy.yaml
+    with:
+      staging_host: staging2.testrun.org
+      mail_domain: staging2.testrun.org
+      zone_file: staging.testrun.org-default.zone
+    secrets: inherit

.github/workflows/trigger-docker-build.yaml

@@ -0,0 +1,24 @@
+name: Trigger Docker image build
+
+on:
+  workflow_call:
+
+jobs:
+  trigger-docker-build:
+    name: Trigger Docker image build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/github-script@v7
+        with:
+          github-token: ${{ secrets.CHATMAIL_DOCKER_DISPATCH_TOKEN }}
+          script: |
+            await github.rest.repos.createDispatchEvent({
+              owner: 'chatmail',
+              repo: 'docker',
+              event_type: 'relay-updated',
+              client_payload: {
+                relay_ref: context.ref,
+                relay_sha: context.sha,
+                relay_sha_short: context.sha.slice(0, 7)
+              }
+            })

chatmaild/pyproject.toml

@@ -6,10 +6,7 @@ build-backend = "setuptools.build_meta"
 name = "chatmaild"
 version = "0.3"
 dependencies = [
-  "aiosmtpd",
   "iniconfig",
-  "deltachat-rpc-server",
-  "deltachat-rpc-client",
   "filelock",
   "requests",
   "crypt-r >= 3.13.1 ; python_version >= '3.11'",
@@ -70,6 +67,7 @@ commands =
 deps = pytest 
        pdbpp 
        pytest-localserver
+       aiosmtpd
        execnet
 commands = pytest -v -rsXx {posargs}
 """

chatmaild/src/chatmaild/config.py

@@ -1,4 +1,3 @@
-import ipaddress
 import os
 from pathlib import Path
 
@@ -21,10 +20,7 @@ def read_config(inipath):
 class Config:
     def __init__(self, inipath, params):
         self._inipath = inipath
-        if is_valid_ipv4(params["mail_domain"]):
-            self.mail_domain = f"[{params.get('mail_domain')}]"
-        else:
-            self.mail_domain = params["mail_domain"]
+        self.mail_domain = params["mail_domain"]
         self.max_user_send_per_minute = int(params.get("max_user_send_per_minute", 60))
         self.max_user_send_burst_size = int(params.get("max_user_send_burst_size", 10))
         self.max_mailbox_size = params["max_mailbox_size"]
@@ -42,6 +38,7 @@ class Config:
         self.filtermail_smtp_port_incoming = int(
             params.get("filtermail_smtp_port_incoming", "10081")
         )
+        self.filtermail_http_port = int(params.get("filtermail_http_port", "10082"))
         self.postfix_reinject_port = int(params.get("postfix_reinject_port", "10025"))
         self.postfix_reinject_port_incoming = int(
             params.get("postfix_reinject_port_incoming", "10026")
@@ -80,7 +77,7 @@ class Config:
                 )
             self.tls_cert_mode = "external"
             self.tls_cert_path, self.tls_key_path = parts
-        elif self.mail_domain.startswith("_") or is_valid_ipv4(params["mail_domain"]):
+        elif self.mail_domain.startswith("_"):
             self.tls_cert_mode = "self"
             self.tls_cert_path = "/etc/ssl/certs/mailserver.pem"
             self.tls_key_path = "/etc/ssl/private/mailserver.key"
@@ -161,12 +158,3 @@ def get_default_config_content(mail_domain, **overrides):
                 lines.append(line)
         content = "\n".join(lines)
     return content
-
-
-def is_valid_ipv4(address: str) -> bool:
-    """Check if a mail_domain is an IPv4 address."""
-    try:
-        ipaddress.IPv4Address(address)
-        return True
-    except ValueError:
-        return False

chatmaild/src/chatmaild/newemail.py

@@ -7,7 +7,7 @@ import secrets
 import string
 from urllib.parse import quote
 
-from chatmaild.config import Config, is_valid_ipv4, read_config
+from chatmaild.config import Config, read_config
 
 CONFIG_PATH = "/usr/local/lib/chatmaild/chatmail.ini"
 ALPHANUMERIC = string.ascii_lowercase + string.digits
@@ -31,15 +31,7 @@ def create_dclogin_url(email, password):
     Uses ic=3 (AcceptInvalidCertificates) so chatmail clients
     can connect to servers with self-signed TLS certificates.
     """
-    domain = email.split("@")[-1]
-    domain_without_brackets = domain.strip("[").strip("]")
-    if is_valid_ipv4(domain_without_brackets):
-        imap_host = "&ih=" + domain_without_brackets
-        smtp_host = "&sh=" + domain_without_brackets
-    else:
-        imap_host = ""
-        smtp_host = ""
-    return f"dclogin:{quote(email, safe='@[]')}?p={quote(password, safe='')}&v=1{imap_host}{smtp_host}&ic=3"
+    return f"dclogin:{quote(email, safe='@')}?p={quote(password, safe='')}&v=1&ic=3"
 
 
 def print_new_account():

cmdeploy/pyproject.toml

@@ -10,7 +10,6 @@ dependencies = [
   "pillow",
   "qrcode",
   "markdown",
-  "pytest",
   "setuptools>=68",
   "termcolor",
   "build",
@@ -21,6 +20,7 @@ dependencies = [
   "execnet",
   "imap_tools",
   "deltachat-rpc-client",
+  "deltachat-rpc-server",
 ]
 
 [project.scripts]

cmdeploy/src/cmdeploy/basedeploy.py

@@ -1,7 +1,10 @@
 import importlib.resources
 import io
 import os
+from contextlib import contextmanager
 
+from pyinfra import host
+from pyinfra.facts.server import Command
 from pyinfra.operations import files, server, systemd
 
 
@@ -10,6 +13,39 @@ def has_systemd():
     return os.path.isdir("/run/systemd/system")
 
 
+def is_in_container() -> bool:
+    """Return True if running inside a container (Docker, LXC, etc.)."""
+    return (
+        host.get_fact(
+            Command,
+            "systemd-detect-virt --container --quiet 2>/dev/null && echo yes || true",
+        )
+        == "yes"
+    )
+
+
+@contextmanager
+def blocked_service_startup():
+    """Prevent services from auto-starting during package installation.
+
+    Installs a ``/usr/sbin/policy-rc.d`` that exits 101, blocking any
+    service from being started by the package manager.  This avoids bind
+    conflicts and CPU/RAM spikes during initial setup.  The file is removed
+    when the context exits.
+    """
+    # For documentation about policy-rc.d, see:
+    # https://people.debian.org/~hmh/invokerc.d-policyrc.d-specification.txt
+    files.put(
+        src=get_resource("policy-rc.d"),
+        dest="/usr/sbin/policy-rc.d",
+        user="root",
+        group="root",
+        mode="755",
+    )
+    yield
+    files.file("/usr/sbin/policy-rc.d", present=False)
+
+
 def get_resource(arg, pkg=__package__):
     return importlib.resources.files(pkg).joinpath(arg)
 

cmdeploy/src/cmdeploy/chatmail.zone.j2

@@ -1,32 +0,0 @@
-;
-; Required DNS entries for chatmail servers 
-;
-{% if A %}
-{{ mail_domain }}.                   A     {{ A }}
-{% endif %}
-{% if AAAA %}
-{{ mail_domain }}.                   AAAA  {{ AAAA }}
-{% endif %}
-{{ mail_domain }}.                   MX 10 {{ mail_domain }}.
-{% if strict_tls %}
-_mta-sts.{{ mail_domain }}.          TXT "v=STSv1; id={{ sts_id }}"
-mta-sts.{{ mail_domain }}.           CNAME {{ mail_domain }}.
-{% endif %}
-www.{{ mail_domain }}.               CNAME {{ mail_domain }}.
-{{ dkim_entry }}
-
-;
-; Recommended DNS entries for interoperability and security-hardening
-;
-{{ mail_domain }}.                   TXT "v=spf1 a ~all"
-_dmarc.{{ mail_domain }}.            TXT "v=DMARC1;p=reject;adkim=s;aspf=s"
-
-{% if acme_account_url %}
-{{ mail_domain }}.                   CAA 0 issue "letsencrypt.org;accounturi={{ acme_account_url }}"
-{% endif %}
-_adsp._domainkey.{{ mail_domain }}.  TXT "dkim=discardable"
-
-_submission._tcp.{{ mail_domain }}.  SRV 0 1 587 {{ mail_domain }}.
-_submissions._tcp.{{ mail_domain }}. SRV 0 1 465 {{ mail_domain }}.
-_imap._tcp.{{ mail_domain }}.        SRV 0 1 143 {{ mail_domain }}.
-_imaps._tcp.{{ mail_domain }}.       SRV 0 1 993 {{ mail_domain }}.

cmdeploy/src/cmdeploy/cmdeploy.py

@@ -13,7 +13,7 @@ import sys
 from pathlib import Path
 
 import pyinfra
-from chatmaild.config import read_config, write_initial_config, is_valid_ipv4
+from chatmaild.config import read_config, write_initial_config
 from packaging import version
 from termcolor import colored
 
@@ -87,11 +87,11 @@ def run_cmd_options(parser):
 def run_cmd(args, out):
     """Deploy chatmail services on the remote server."""
 
-    ssh_host = args.ssh_host if args.ssh_host else args.config.mail_domain.strip("[").strip("]")
+    ssh_host = args.ssh_host if args.ssh_host else args.config.mail_domain
     sshexec = get_sshexec(ssh_host)
     require_iroh = args.config.enable_iroh_relay
     strict_tls = args.config.tls_cert_mode == "acme"
-    if not args.dns_check_disabled and not is_valid_ipv4(args.config.mail_domain.strip("[").strip("]")):
+    if not args.dns_check_disabled:
         remote_data = dns.get_initial_remote_data(sshexec, args.config.mail_domain)
         if not dns.check_initial_remote_data(remote_data, strict_tls=strict_tls, print=out.red):
             return 1
@@ -101,17 +101,14 @@ def run_cmd(args, out):
     env["CHATMAIL_WEBSITE_ONLY"] = "True" if args.website_only else ""
     env["CHATMAIL_DISABLE_MAIL"] = "True" if args.disable_mail else ""
     env["CHATMAIL_REQUIRE_IROH"] = "True" if require_iroh else ""
-    if not args.dns_check_disabled and not is_valid_ipv4(args.config.mail_domain.strip("[").strip("]")):
+    if not args.dns_check_disabled:
         env["CHATMAIL_ADDR_V4"] = remote_data.get("A") or ""
         env["CHATMAIL_ADDR_V6"] = remote_data.get("AAAA") or ""
     deploy_path = importlib.resources.files(__package__).joinpath("run.py").resolve()
     pyinf = "pyinfra --dry" if args.dry_run else "pyinfra"
 
     cmd = f"{pyinf} --ssh-user root {ssh_host} {deploy_path} -y"
-    if ssh_host in ["localhost", "@docker"]:
-        if ssh_host == "@docker":
-            env["CHATMAIL_NOPORTCHECK"] = "True"
-            env["CHATMAIL_NOSYSCTL"] = "True"
+    if ssh_host == "localhost":
         cmd = f"{pyinf} @local {deploy_path} -y"
 
     if version.parse(pyinfra.__version__) < version.parse("3"):
@@ -210,6 +207,7 @@ def test_cmd(args, out):
     """Run local and online tests for chatmail deployment."""
 
     env = os.environ.copy()
+    env["CHATMAIL_INI"] = str(args.inipath.absolute())
     if args.ssh_host:
         env["CHATMAIL_SSH"] = args.ssh_host
 
@@ -316,7 +314,7 @@ def add_ssh_host_option(parser):
     parser.add_argument(
         "--ssh-host",
         dest="ssh_host",
-        help="Run commands on 'localhost', via '@docker', or on a specific SSH host "
+        help="Run commands on 'localhost' or on a specific SSH host "
         "instead of chatmail.ini's mail_domain.",
     )
 
@@ -378,9 +376,7 @@ def get_parser():
 
 def get_sshexec(ssh_host: str, verbose=True):
     if ssh_host in ["localhost", "@local"]:
-        return LocalExec(verbose, docker=False)
-    elif ssh_host == "@docker":
-        return LocalExec(verbose, docker=True)
+        return LocalExec(verbose)
     if verbose:
         print(f"[ssh] login to {ssh_host}")
     return SSHExec(ssh_host, verbose=verbose)

cmdeploy/src/cmdeploy/deployers.py

@@ -2,7 +2,6 @@
 Chat Mail pyinfra deploy.
 """
 
-import os
 import shutil
 import subprocess
 import sys
@@ -24,9 +23,11 @@ from .basedeploy import (
     Deployer,
     Deployment,
     activate_remote_units,
+    blocked_service_startup,
     configure_remote_units,
     get_resource,
     has_systemd,
+    is_in_container,
 )
 from .dovecot.deployer import DovecotDeployer
 from .external.deployer import ExternalTlsDeployer
@@ -149,33 +150,16 @@ class UnboundDeployer(Deployer):
         self.need_restart = False
 
     def install(self):
-        # Run local DNS resolver `unbound`.
-        # `resolvconf` takes care of setting up /etc/resolv.conf
-        # to use 127.0.0.1 as the resolver.
+        # Run local DNS resolver `unbound`. `resolvconf` takes care of
+        # setting up /etc/resolv.conf to use 127.0.0.1 as the resolver.
 
-        #
-        # On an IPv4-only system, if unbound is started but not
-        # configured, it causes subsequent steps to fail to resolve hosts.
-        # Here, we use policy-rc.d to prevent unbound from starting up
-        # on initial install.  Later, we will configure it and start it.
-        #
-        # For documentation about policy-rc.d, see:
-        # https://people.debian.org/~hmh/invokerc.d-policyrc.d-specification.txt
-        #
-        files.put(
-            src=get_resource("policy-rc.d"),
-            dest="/usr/sbin/policy-rc.d",
-            user="root",
-            group="root",
-            mode="755",
-        )
-
-        apt.packages(
-            name="Install unbound",
-            packages=["unbound", "unbound-anchor", "dnsutils"],
-        )
-
-        files.file("/usr/sbin/policy-rc.d", present=False)
+        # On an IPv4-only system, if unbound is started but not configured,
+        # it causes subsequent steps to fail to resolve hosts.
+        with blocked_service_startup():
+            apt.packages(
+                name="Install unbound",
+                packages=["unbound", "unbound-anchor", "dnsutils"],
+            )
 
     def configure(self):
         server.shell(
@@ -336,12 +320,12 @@ class TurnDeployer(Deployer):
     def install(self):
         (url, sha256sum) = {
             "x86_64": (
-                "https://github.com/chatmail/chatmail-turn/releases/download/v0.3/chatmail-turn-x86_64-linux",
-                "841e527c15fdc2940b0469e206188ea8f0af48533be12ecb8098520f813d41e4",
+                "https://github.com/chatmail/chatmail-turn/releases/download/v0.4/chatmail-turn-x86_64-linux",
+                "1ec1f5c50122165e858a5a91bcba9037a28aa8cb8b64b8db570aa457c6141a8a",
             ),
             "aarch64": (
-                "https://github.com/chatmail/chatmail-turn/releases/download/v0.3/chatmail-turn-aarch64-linux",
-                "a5fc2d06d937b56a34e098d2cd72a82d3e89967518d159bf246dc69b65e81b42",
+                "https://github.com/chatmail/chatmail-turn/releases/download/v0.4/chatmail-turn-aarch64-linux",
+                "0fb3e792419494e21ecad536464929dba706bb2c88884ed8f1788141d26fc756",
             ),
         }[host.get_fact(facts.server.Arch)]
 
@@ -474,8 +458,9 @@ class ChatmailDeployer(Deployer):
         ("iroh", None, None),
     ]
 
-    def __init__(self, mail_domain):
-        self.mail_domain = mail_domain
+    def __init__(self, config):
+        self.config = config
+        self.mail_domain = config.mail_domain
 
     def install(self):
         files.put(
@@ -498,12 +483,18 @@ class ChatmailDeployer(Deployer):
             name="Install rsync",
             packages=["rsync"],
         )
-        apt.packages(
-            name="Ensure cron is installed",
-            packages=["cron"],
-        )
 
     def configure(self):
+        # metadata crashes if the mailboxes dir does not exist
+        files.directory(
+            name="Ensure vmail mailbox directory exists",
+            path=str(self.config.mailboxes_dir),
+            user="vmail",
+            group="vmail",
+            mode="700",
+            present=True,
+        )
+
         # This file is used by auth proxy.
         # https://wiki.debian.org/EtcMailName
         server.shell(
@@ -593,7 +584,7 @@ def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -
             Out().red(f"Deploy failed: mtail_address {config.mtail_address} is not available (VPN up?).\n")
             exit(1)
 
-    if not os.environ.get("CHATMAIL_NOPORTCHECK"):
+    if not is_in_container():
         port_services = [
             (["master", "smtpd"], 25),
             ("unbound", 53),
@@ -633,7 +624,7 @@ def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -
     tls_deployer = get_tls_deployer(config, mail_domain)
 
     all_deployers = [
-        ChatmailDeployer(mail_domain),
+        ChatmailDeployer(config),
         LegacyRemoveDeployer(),
         FiltermailDeployer(),
         JournaldDeployer(),

cmdeploy/src/cmdeploy/dns.py

@@ -1,11 +1,22 @@
 import datetime
-import importlib
-
-from jinja2 import Template
 
 from . import remote
 
 
+def parse_zone_records(text):
+    """Yield ``(name, ttl, rtype, rdata)`` from standard BIND-format text."""
+    for raw_line in text.splitlines():
+        line = raw_line.strip()
+        if not line or line.startswith(";"):
+            continue
+        try:
+            name, ttl, _in, rtype, rdata = line.split(None, 4)
+        except ValueError:
+            raise ValueError(f"Bad zone record line: {line!r}") from None
+        name = name.rstrip(".")
+        yield name, ttl, rtype.upper(), rdata
+
+
 def get_initial_remote_data(sshexec, mail_domain):
     return sshexec.logged(
         call=remote.rdns.perform_initial_checks, kwargs=dict(mail_domain=mail_domain)
@@ -31,13 +42,39 @@ def get_filled_zone_file(remote_data):
     if not sts_id:
         remote_data["sts_id"] = datetime.datetime.now().strftime("%Y%m%d%H%M")
 
-    template = importlib.resources.files(__package__).joinpath("chatmail.zone.j2")
-    content = template.read_text()
-    zonefile = Template(content).render(**remote_data)
-    lines = [x.strip() for x in zonefile.split("\n") if x.strip()]
+    d = remote_data["mail_domain"]
+
+    def append_record(name, rtype, rdata, ttl=3600):
+        lines.append(f"{name:<40} {ttl:<6} IN  {rtype:<5}  {rdata}")
+
+    lines = ["; Required DNS entries"]
+    if remote_data.get("A"):
+        append_record(f"{d}.", "A", remote_data["A"])
+    if remote_data.get("AAAA"):
+        append_record(f"{d}.", "AAAA", remote_data["AAAA"])
+    append_record(f"{d}.", "MX", f"10 {d}.")
+    if remote_data.get("strict_tls"):
+        append_record(f"_mta-sts.{d}.", "TXT", f'"v=STSv1; id={remote_data["sts_id"]}"')
+        append_record(f"mta-sts.{d}.", "CNAME", f"{d}.")
+    append_record(f"www.{d}.", "CNAME", f"{d}.")
+    lines.append(remote_data["dkim_entry"])
     lines.append("")
-    zonefile = "\n".join(lines)
-    return zonefile
+    lines.append("; Recommended DNS entries")
+    append_record(f"{d}.", "TXT", '"v=spf1 a ~all"')
+    append_record(f"_dmarc.{d}.", "TXT", '"v=DMARC1;p=reject;adkim=s;aspf=s"')
+    if remote_data.get("acme_account_url"):
+        append_record(
+            f"{d}.",
+            "CAA",
+            f'0 issue "letsencrypt.org;accounturi={remote_data["acme_account_url"]}"',
+        )
+    append_record(f"_adsp._domainkey.{d}.", "TXT", '"dkim=discardable"')
+    append_record(f"_submission._tcp.{d}.", "SRV", f"0 1 587 {d}.")
+    append_record(f"_submissions._tcp.{d}.", "SRV", f"0 1 465 {d}.")
+    append_record(f"_imap._tcp.{d}.", "SRV", f"0 1 143 {d}.")
+    append_record(f"_imaps._tcp.{d}.", "SRV", f"0 1 993 {d}.")
+    lines.append("")
+    return "\n".join(lines)
 
 
 def check_full_zone(sshexec, remote_data, out, zonefile) -> int:
@@ -58,7 +95,8 @@ def check_full_zone(sshexec, remote_data, out, zonefile) -> int:
         returncode = 1
     if remote_data.get("dkim_entry") in required_diff:
         out(
-            "If the DKIM entry above does not work with your DNS provider, you can try this one:\n"
+            "If the DKIM entry above does not work with your DNS provider,"
+            " you can try this one:\n"
         )
         out(remote_data.get("web_dkim_entry") + "\n")
     if recommended_diff:

cmdeploy/src/cmdeploy/dovecot/deployer.py

@@ -1,20 +1,33 @@
-import os
+import io
 import urllib.request
 
 from chatmaild.config import Config
 from pyinfra import host
+from pyinfra.facts.deb import DebPackages
 from pyinfra.facts.server import Arch, Sysctl
-from pyinfra.facts.systemd import SystemdEnabled
 from pyinfra.operations import apt, files, server, systemd
 
 from cmdeploy.basedeploy import (
     Deployer,
     activate_remote_units,
+    blocked_service_startup,
     configure_remote_units,
     get_resource,
-    has_systemd,
+    is_in_container,
 )
 
+DOVECOT_ARCHIVE_VERSION = "2.3.21+dfsg1-3"
+DOVECOT_PACKAGE_VERSION = f"1:{DOVECOT_ARCHIVE_VERSION}"
+
+DOVECOT_SHA256 = {
+    ("core", "amd64"): "dd060706f52a306fa863d874717210b9fe10536c824afe1790eec247ded5b27d",
+    ("core", "arm64"): "e7548e8a82929722e973629ecc40fcfa886894cef3db88f23535149e7f730dc9",
+    ("imapd", "amd64"): "8d8dc6fc00bbb6cdb25d345844f41ce2f1c53f764b79a838eb2a03103eebfa86",
+    ("imapd", "arm64"): "178fa877ddd5df9930e8308b518f4b07df10e759050725f8217a0c1fb3fd707f",
+    ("lmtpd", "amd64"): "2f69ba5e35363de50962d42cccbfe4ed8495265044e244007d7ccddad77513ab",
+    ("lmtpd", "arm64"): "89f52fb36524f5877a177dff4a713ba771fd3f91f22ed0af7238d495e143b38f",
+}
+
 
 class DovecotDeployer(Deployer):
     daemon_reload = False
@@ -26,15 +39,43 @@ class DovecotDeployer(Deployer):
 
     def install(self):
         arch = host.get_fact(Arch)
-        if has_systemd() and "dovecot.service" in host.get_fact(SystemdEnabled):
-            return  # already installed and running
-        _install_dovecot_package("core", arch)
-        _install_dovecot_package("imapd", arch)
-        _install_dovecot_package("lmtpd", arch)
+        with blocked_service_startup():
+            debs = []
+            for pkg in ("core", "imapd", "lmtpd"):
+                deb, changed = _download_dovecot_package(pkg, arch)
+                self.need_restart |= changed
+                if deb:
+                    debs.append(deb)
+            if debs:
+                deb_list = " ".join(debs)
+                # First dpkg may fail on missing dependencies (stderr suppressed);
+                # apt-get --fix-broken pulls them in, then dpkg retries cleanly.
+                server.shell(
+                    name="Install dovecot packages",
+                    commands=[
+                        f"dpkg --force-confdef --force-confold -i {deb_list} 2> /dev/null || true",
+                        "DEBIAN_FRONTEND=noninteractive apt-get -y --fix-broken install",
+                        f"dpkg --force-confdef --force-confold -i {deb_list}",
+                    ],
+                )
+                self.need_restart = True
+        files.put(
+            name="Pin dovecot packages to block Debian dist-upgrades",
+            src=io.StringIO(
+                "Package: dovecot-*\n"
+                "Pin: version *\n"
+                "Pin-Priority: -1\n"
+            ),
+            dest="/etc/apt/preferences.d/pin-dovecot",
+            user="root",
+            group="root",
+            mode="644",
+        )
 
     def configure(self):
         configure_remote_units(self.config.mail_domain, self.units)
-        self.need_restart, self.daemon_reload = _configure_dovecot(self.config)
+        config_restart, self.daemon_reload = _configure_dovecot(self.config)
+        self.need_restart |= config_restart
 
     def activate(self):
         activate_remote_units(self.units)
@@ -63,43 +104,40 @@ def _pick_url(primary, fallback):
         return fallback
 
 
-def _install_dovecot_package(package: str, arch: str):
+def _download_dovecot_package(package: str, arch: str) -> tuple[str | None, bool]:
+    """Download a dovecot .deb if needed, return (path, changed)."""
     arch = "amd64" if arch == "x86_64" else arch
     arch = "arm64" if arch == "aarch64" else arch
-    primary_url = f"https://download.delta.chat/dovecot/dovecot-{package}_2.3.21%2Bdfsg1-3_{arch}.deb"
-    fallback_url = f"https://github.com/chatmail/dovecot/releases/download/upstream%2F2.3.21%2Bdfsg1/dovecot-{package}_2.3.21%2Bdfsg1-3_{arch}.deb"
-    url = _pick_url(primary_url, fallback_url)
-    deb_filename = "/root/" + url.split("/")[-1]
 
-    match (package, arch):
-        case ("core", "amd64"):
-            sha256 = "dd060706f52a306fa863d874717210b9fe10536c824afe1790eec247ded5b27d"
-        case ("core", "arm64"):
-            sha256 = "e7548e8a82929722e973629ecc40fcfa886894cef3db88f23535149e7f730dc9"
-        case ("imapd", "amd64"):
-            sha256 = "8d8dc6fc00bbb6cdb25d345844f41ce2f1c53f764b79a838eb2a03103eebfa86"
-        case ("imapd", "arm64"):
-            sha256 = "178fa877ddd5df9930e8308b518f4b07df10e759050725f8217a0c1fb3fd707f"
-        case ("lmtpd", "amd64"):
-            sha256 = "2f69ba5e35363de50962d42cccbfe4ed8495265044e244007d7ccddad77513ab"
-        case ("lmtpd", "arm64"):
-            sha256 = "89f52fb36524f5877a177dff4a713ba771fd3f91f22ed0af7238d495e143b38f"
-        case _:
-            apt.packages(packages=[f"dovecot-{package}"])
-            return
+    pkg_name = f"dovecot-{package}"
+    sha256 = DOVECOT_SHA256.get((package, arch))
+    if sha256 is None:
+        op = apt.packages(packages=[pkg_name])
+        return None, bool(getattr(op, "changed", False))
+
+    installed_versions = host.get_fact(DebPackages).get(pkg_name, [])
+    if DOVECOT_PACKAGE_VERSION in installed_versions:
+        return None, False
+
+    url_version = DOVECOT_ARCHIVE_VERSION.replace("+", "%2B")
+    deb_base = f"{pkg_name}_{url_version}_{arch}.deb"
+    primary_url = f"https://download.delta.chat/dovecot/{deb_base}"
+    fallback_url = f"https://github.com/chatmail/dovecot/releases/download/upstream%2F{url_version}/{deb_base}"
+    url = _pick_url(primary_url, fallback_url)
+    deb_filename = f"/root/{deb_base}"
 
     files.download(
-        name=f"Download dovecot-{package}",
+        name=f"Download {pkg_name}",
         src=url,
         dest=deb_filename,
         sha256sum=sha256,
         cache_time=60 * 60 * 24 * 365 * 10,  # never redownload the package
     )
 
-    apt.deb(name=f"Install dovecot-{package}", src=deb_filename)
+    return deb_filename, True
 
 
-def _configure_dovecot(config: Config, debug: bool = False) -> (bool, bool):
+def _configure_dovecot(config: Config, debug: bool = False) -> tuple[bool, bool]:
     """Configures Dovecot IMAP server."""
     need_restart = False
     daemon_reload = False
@@ -134,19 +172,25 @@ def _configure_dovecot(config: Config, debug: bool = False) -> (bool, bool):
 
     # as per https://doc.dovecot.org/2.3/configuration_manual/os/
     # it is recommended to set the following inotify limits
-    if not os.environ.get("CHATMAIL_NOSYSCTL"):
-        for name in ("max_user_instances", "max_user_watches"):
-            key = f"fs.inotify.{name}"
-            if host.get_fact(Sysctl)[key] > 65535:
-                # Skip updating limits if already sufficient
-                # (enables running in incus containers where sysctl readonly)
-                continue
-            server.sysctl(
-                name=f"Change {key}",
-                key=key,
-                value=65535,
-                persist=True,
+    can_modify = not is_in_container()
+    for name in ("max_user_instances", "max_user_watches"):
+        key = f"fs.inotify.{name}"
+        value = host.get_fact(Sysctl)[key]
+        if value > 65534:
+            continue
+        if not can_modify:
+            print(
+                "\n!!!! refusing to attempt sysctl setting in containers\n"
+                f"!!!! dovecot: sysctl {key!r}={value}, should be >65534 for production setups\n"
+                "!!!!"
             )
+            continue
+        server.sysctl(
+            name=f"Change {key}",
+            key=key,
+            value=65535,
+            persist=True,
+        )
 
     timezone_env = files.line(
         name="Set TZ environment variable",

cmdeploy/src/cmdeploy/dovecot/dovecot.conf.j2

@@ -7,7 +7,6 @@ listen = 0.0.0.0
 protocols = imap lmtp
 
 auth_mechanisms = plain
-auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@[]
 
 {% if debug == true %}
 auth_verbose = yes

cmdeploy/src/cmdeploy/filtermail/deployer.py

@@ -14,10 +14,10 @@ class FiltermailDeployer(Deployer):
 
     def install(self):
         arch = host.get_fact(facts.server.Arch)
-        url = f"https://github.com/chatmail/filtermail/releases/download/v0.5.2/filtermail-{arch}"
+        url = f"https://github.com/chatmail/filtermail/releases/download/v0.6.1/filtermail-{arch}"
         sha256sum = {
-            "x86_64": "ce24ca0075aa445510291d775fb3aea8f4411818c7b885ae51a0fe18c5f789ce",
-            "aarch64": "c5d783eefa5332db3d97a0e6a23917d72849e3eb45da3d16ce908a9b4e5a797d",
+            "x86_64": "48b3fb80c092d00b9b0a0ef77a8673496da3b9aed5ec1851e1df936d5589d62f",
+            "aarch64": "c65bd5f45df187d3d65d6965a285583a3be0f44a6916ff12909ff9a8d702c22e",
         }[arch]
         self.need_restart |= files.download(
             name="Download filtermail",

cmdeploy/src/cmdeploy/nginx/nginx.conf.j2

@@ -73,6 +73,10 @@ http {
 
 		access_log syslog:server=unix:/dev/log,facility=local7;
 
+		location /mxdeliv/ {
+		    proxy_pass http://127.0.0.1:{{ config.filtermail_http_port }};
+		}
+
 		location / {
 			# First attempt to serve request as file, then
 			# as directory, then fall back to displaying a 404.

cmdeploy/src/cmdeploy/postfix/main.cf.j2

@@ -20,7 +20,7 @@ smtpd_tls_key_file={{ config.tls_key_path }}
 smtpd_tls_security_level=may
 
 smtp_tls_CApath=/etc/ssl/certs
-smtp_tls_security_level={{ "verify" if config.tls_cert_mode == "acme" else "encrypt" }}
+smtp_tls_security_level=verify
 # Send SNI extension when connecting to other servers.
 # <https://www.postfix.org/postconf.5.html#smtp_tls_servername>
 smtp_tls_servername = hostname
@@ -54,15 +54,14 @@ smtpd_tls_exclude_ciphers = aNULL, RC4, MD5, DES
 tls_preempt_cipherlist = yes
 
 smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
+myhostname = {{ config.mail_domain }}
 alias_maps = hash:/etc/aliases
 alias_database = hash:/etc/aliases
 
 # Postfix does not deliver mail for any domain by itself.
 # Primary domain is listed in `virtual_mailbox_domains` instead
 # and handed over to Dovecot.
-mydestination = {{ config.mail_domain }}
-local_transport = lmtp:unix:private/dovecot-lmtp
-local_recipient_maps =
+mydestination =
 
 relayhost = 
 {% if disable_ipv6 %}
@@ -89,6 +88,24 @@ inet_protocols = ipv4
 inet_protocols = all
 {% endif %}
 
+# Postfix does not try IPv4 and IPv6 connections
+# concurrently as of version 3.7.11.
+#
+# When relay has both A (IPv4) and AAAA (IPv6) records,
+# but broken IPv6 connectivity,
+# every second message is delayed by the connection timeout
+# <https://www.postfix.org/postconf.5.html#smtp_connect_timeout>
+# which defaults to 30 seconds. Reducing timeouts is not a solution
+# as this will result in a failure to connect to slow servers.
+#
+# As a workaround we always prefer IPv4 when it is available.
+# 
+# The setting is documented at
+# <https://www.postfix.org/postconf.5.html#smtp_address_preference>
+smtp_address_preference=ipv4
+
+virtual_transport = lmtp:unix:private/dovecot-lmtp
+virtual_mailbox_domains = {{ config.mail_domain }}
 lmtp_header_checks = regexp:/etc/postfix/lmtp_header_cleanup
 
 mua_client_restrictions = permit_sasl_authenticated, reject

cmdeploy/src/cmdeploy/postfix/master.cf.j2

@@ -80,9 +80,7 @@ filter    unix -        n       n       -       -       lmtp
 127.0.0.1:{{ config.postfix_reinject_port }} inet  n       -       n       -       100      smtpd
   -o syslog_name=postfix/reinject
   -o milter_macro_daemon_name=ORIGINATING
-{% if "[" not in config.mail_domain %}
   -o smtpd_milters=unix:opendkim/opendkim.sock
-{% endif %}
   -o cleanup_service_name=authclean
 
 # Local SMTP server for reinjecting incoming filtered mail 

cmdeploy/src/cmdeploy/remote/rdns.py

@@ -57,9 +57,10 @@ def get_dkim_entry(mail_domain, pre_command, dkim_selector):
     dkim_value_raw = f"v=DKIM1;k=rsa;p={dkim_pubkey};s=email;t=s"
     dkim_value = '" "'.join(re.findall(".{1,255}", dkim_value_raw))
     web_dkim_value = "".join(re.findall(".{1,255}", dkim_value_raw))
+    name = f"{dkim_selector}._domainkey.{mail_domain}."
     return (
-        f'{dkim_selector}._domainkey.{mail_domain}. TXT "{dkim_value}"',
-        f'{dkim_selector}._domainkey.{mail_domain}. TXT "{web_dkim_value}"',
+        f'{name:<40} 3600   IN  TXT    "{dkim_value}"',
+        f'{name:<40} 3600   IN  TXT    "{web_dkim_value}"',
     )
 
 
@@ -94,7 +95,7 @@ def check_zonefile(zonefile, verbose=True):
         if not zf_line.strip() or zf_line.startswith(";"):
             continue
         print(f"dns-checking {zf_line!r}") if verbose else log_progress("")
-        zf_domain, zf_typ, zf_value = zf_line.split(maxsplit=2)
+        zf_domain, _ttl, _in, zf_typ, zf_value = zf_line.split(None, 4)
         zf_domain = zf_domain.rstrip(".")
         zf_value = zf_value.strip()
         query_value = query_dns(zf_typ, zf_domain)

cmdeploy/src/cmdeploy/selfsigned/deployer.py

@@ -18,6 +18,8 @@ def openssl_selfsigned_args(domain, cert_path, key_path, days=36500):
         "-keyout", str(key_path),
         "-out", str(cert_path),
         "-subj", f"/CN={domain}",
+        # Mark as end-entity cert so it cannot be used as a CA to sign others.
+        "-addext", "basicConstraints=critical,CA:FALSE",
         "-addext", "extendedKeyUsage=serverAuth,clientAuth",
         "-addext",
         f"subjectAltName=DNS:{domain},DNS:www.{domain},DNS:mta-sts.{domain}",

cmdeploy/src/cmdeploy/sshexec.py

@@ -87,9 +87,8 @@ class SSHExec:
 class LocalExec:
     FuncError = FuncError
 
-    def __init__(self, verbose=False, docker=False):
+    def __init__(self, verbose=False):
         self.verbose = verbose
-        self.docker = docker
 
     def __call__(self, call, kwargs=None, log_callback=None):
         if kwargs is None:
@@ -101,10 +100,6 @@ class LocalExec:
         if not title:
             title = call.__name__
         where = "locally"
-        if self.docker:
-            if call == remote.rdns.perform_initial_checks:
-                kwargs["pre_command"] = "docker exec chatmail "
-                where = "in docker"
         if self.verbose:
             print_stderr(f"Running {where}: {title}(**{kwargs})")
             return self(call, kwargs, log_callback=print_stderr)

cmdeploy/src/cmdeploy/tests/data/zftest.zone

@@ -1,17 +1,18 @@
-; Required DNS entries for chatmail servers
-zftest.testrun.org.                   A     135.181.204.127
-zftest.testrun.org.                   AAAA  2a01:4f9:c012:52f4::1
-zftest.testrun.org.                   MX 10 zftest.testrun.org.
-_mta-sts.zftest.testrun.org.          TXT "v=STSv1; id=202403211706"
-mta-sts.zftest.testrun.org.           CNAME zftest.testrun.org.
-www.zftest.testrun.org.               CNAME zftest.testrun.org.
-opendkim._domainkey.zftest.testrun.org. TXT "v=DKIM1;k=rsa;p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAoYt82CVUyz2ouaqjX2kB+5J80knAyoOU3MGU5aWppmwUwwTvj/oSTSpkc5JMtVTRmKKr8NUDWAL1Yw7dfGqqPHdHfwwjS3BIvDzYx+hzgtz62RnfNgV+/2MAoNpfX7cAFIHdRzEHNtwugc3RDLquqPoupAE3Y2YRw2T5zG5fILh4vwIcJZL5Uq6B92j8wwJqOex" "33n+vm1NKQ9rxo/UsHAmZlJzpooXcG/4igTBxJyJlamVSRR6N7Nul1v//YJb7J6v2o0iPHW6uE0StzKaPPNC2IVosSRFbD9H2oqppltptFSNPlI0E+t0JBWHem6YK7xcugiO3ImMCaaU8g6Jt/wIDAQAB;s=email;t=s"
+; Required DNS entries
+zftest.testrun.org.                      3600   IN  A      135.181.204.127
+zftest.testrun.org.                      3600   IN  AAAA   2a01:4f9:c012:52f4::1
+zftest.testrun.org.                      3600   IN  MX     10 zftest.testrun.org.
+_mta-sts.zftest.testrun.org.             3600   IN  TXT    "v=STSv1; id=202403211706"
+mta-sts.zftest.testrun.org.              3600   IN  CNAME  zftest.testrun.org.
+www.zftest.testrun.org.                  3600   IN  CNAME  zftest.testrun.org.
+opendkim._domainkey.zftest.testrun.org.  3600   IN  TXT    "v=DKIM1;k=rsa;p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAoYt82CVUyz2ouaqjX2kB+5J80knAyoOU3MGU5aWppmwUwwTvj/oSTSpkc5JMtVTRmKKr8NUDWAL1Yw7dfGqqPHdHfwwjS3BIvDzYx+hzgtz62RnfNgV+/2MAoNpfX7cAFIHdRzEHNtwugc3RDLquqPoupAE3Y2YRw2T5zG5fILh4vwIcJZL5Uq6B92j8wwJqOex" "33n+vm1NKQ9rxo/UsHAmZlJzpooXcG/4igTBxJyJlamVSRR6N7Nul1v//YJb7J6v2o0iPHW6uE0StzKaPPNC2IVosSRFbD9H2oqppltptFSNPlI0E+t0JBWHem6YK7xcugiO3ImMCaaU8g6Jt/wIDAQAB;s=email;t=s"
+
 ; Recommended DNS entries
-_submission._tcp.zftest.testrun.org.  SRV 0 1 587 zftest.testrun.org.
-_submissions._tcp.zftest.testrun.org. SRV 0 1 465 zftest.testrun.org.
-_imap._tcp.zftest.testrun.org.        SRV 0 1 143 zftest.testrun.org.
-_imaps._tcp.zftest.testrun.org.       SRV 0 1 993 zftest.testrun.org.
-zftest.testrun.org.                   CAA 0 issue "letsencrypt.org;accounturi=https://acme-v02.api.letsencrypt.org/acme/acct/1371472956"
-zftest.testrun.org.                   TXT "v=spf1 a:zftest.testrun.org ~all"
-_dmarc.zftest.testrun.org.            TXT "v=DMARC1;p=reject;adkim=s;aspf=s"
-_adsp._domainkey.zftest.testrun.org.  TXT "dkim=discardable"
+zftest.testrun.org.                      3600   IN  TXT    "v=spf1 a ~all"
+_dmarc.zftest.testrun.org.               3600   IN  TXT    "v=DMARC1;p=reject;adkim=s;aspf=s"
+zftest.testrun.org.                      3600   IN  CAA    0 issue "letsencrypt.org;accounturi=https://acme-v02.api.letsencrypt.org/acme/acct/1371472956"
+_adsp._domainkey.zftest.testrun.org.     3600   IN  TXT    "dkim=discardable"
+_submission._tcp.zftest.testrun.org.     3600   IN  SRV    0 1 587 zftest.testrun.org.
+_submissions._tcp.zftest.testrun.org.    3600   IN  SRV    0 1 465 zftest.testrun.org.
+_imap._tcp.zftest.testrun.org.           3600   IN  SRV    0 1 143 zftest.testrun.org.
+_imaps._tcp.zftest.testrun.org.          3600   IN  SRV    0 1 993 zftest.testrun.org.

cmdeploy/src/cmdeploy/tests/online/benchmark.py

@@ -1,4 +1,3 @@
-import time
 def test_tls_imap(benchmark, imap):
     def imap_connect():
         imap.connect()

cmdeploy/src/cmdeploy/tests/online/test_0_login.py

@@ -8,11 +8,11 @@ from chatmaild.config import read_config
 from cmdeploy.cmdeploy import main
 
 
-def test_init(tmp_path, maildomain_sanitized):
+def test_init(tmp_path, maildomain):
     inipath = tmp_path.joinpath("chatmail.ini")
-    main(["init", "--config", str(inipath), maildomain_sanitized])
+    main(["init", "--config", str(inipath), maildomain])
     config = read_config(inipath)
-    assert config.mail_domain.strip("[").strip("]") == maildomain_sanitized
+    assert config.mail_domain == maildomain
 
 
 def test_capabilities(imap):
@@ -89,16 +89,18 @@ def test_concurrent_logins_same_account(
         assert login_results.get()
 
 
-def test_no_vrfy(chatmail_config):
+def test_no_vrfy(cmfactory, chatmail_config):
+    ac = cmfactory.get_online_account()
+    addr = ac.get_config("addr")
     domain = chatmail_config.mail_domain
 
-    s = smtplib.SMTP(domain.strip("[").strip("]"))
+    s = smtplib.SMTP(domain)
     s.starttls()
 
     s.putcmd("vrfy", f"wrongaddress@{chatmail_config.mail_domain}")
     result = s.getreply()
     print(result)
-    s.putcmd("vrfy", f"echo@{chatmail_config.mail_domain}")
+    s.putcmd("vrfy", addr)
     result2 = s.getreply()
     print(result2)
     assert result[0] == result2[0] == 252

cmdeploy/src/cmdeploy/tests/online/test_0_qr.py

@@ -10,31 +10,31 @@ def test_gen_qr_png_data(maildomain):
 
 
 @pytest.mark.filterwarnings("ignore::urllib3.exceptions.InsecureRequestWarning")
-def test_fastcgi_working(maildomain_sanitized, chatmail_config):
-    url = f"https://{maildomain_sanitized}/new"
+def test_fastcgi_working(maildomain, chatmail_config):
+    url = f"https://{maildomain}/new"
     print(url)
     verify = chatmail_config.tls_cert_mode == "acme"
     res = requests.post(url, verify=verify)
-    assert maildomain_sanitized in res.json().get("email")
+    assert maildomain in res.json().get("email")
     assert len(res.json().get("password")) > chatmail_config.password_min_length
 
 
 @pytest.mark.filterwarnings("ignore::urllib3.exceptions.InsecureRequestWarning")
-def test_newemail_configure(maildomain_sanitized, rpc, chatmail_config):
+def test_newemail_configure(maildomain, rpc, chatmail_config):
     """Test configuring accounts by scanning a QR code works."""
-    url = f"DCACCOUNT:https://{maildomain_sanitized}/new"
+    url = f"DCACCOUNT:https://{maildomain}/new"
     for i in range(3):
         account_id = rpc.add_account()
         if chatmail_config.tls_cert_mode == "self":
             # deltachat core's rustls rejects self-signed HTTPS certs during
             # set_config_from_qr, so fetch credentials via requests instead
-            res = requests.post(f"https://{maildomain_sanitized}/new", verify=False)
+            res = requests.post(f"https://{maildomain}/new", verify=False)
             data = res.json()
             rpc.add_or_update_transport(account_id, {
                 "addr": data["email"],
                 "password": data["password"],
-                "imapServer": maildomain_sanitized,
-                "smtpServer": maildomain_sanitized,
+                "imapServer": maildomain,
+                "smtpServer": maildomain,
                 "certificateChecks": "acceptInvalidCertificates",
             })
         else:

cmdeploy/src/cmdeploy/tests/online/test_1_basic.py

@@ -21,8 +21,6 @@ class TestSSHExecutor:
         assert out == out2
 
     def test_perform_initial(self, sshexec, maildomain):
-        if "[" in maildomain:
-            pytest.skip("Relay doesn't have a domain")
         res = sshexec(
             remote.rdns.perform_initial_checks, kwargs=dict(mail_domain=maildomain)
         )
@@ -73,6 +71,44 @@ class TestSSHExecutor:
         assert (now - since_date).total_seconds() < 60 * 60 * 51
 
 
+def test_dovecot_main_process_matches_installed_binary(sshdomain):
+    sshexec = get_sshexec(sshdomain)
+    main_pid = int(
+        sshexec(
+            call=remote.rshell.shell,
+            kwargs=dict(
+                command="timeout 10 systemctl show -p MainPID --value dovecot.service"
+            ),
+        ).strip()
+    )
+    assert main_pid != 0, "dovecot.service MainPID is 0 -- service not running?"
+
+    exe = sshexec(
+        call=remote.rshell.shell,
+        kwargs=dict(command=f"timeout 10 readlink /proc/{main_pid}/exe"),
+    ).strip()
+    status_text = sshexec(
+        call=remote.rshell.shell,
+        kwargs=dict(
+            command="timeout 10 systemctl show -p StatusText --value dovecot.service"
+        ),
+    ).strip()
+    installed_version = sshexec(
+        call=remote.rshell.shell, kwargs=dict(command="timeout 10 dovecot --version")
+    ).strip()
+
+    assert not exe.endswith("(deleted)"), (
+        f"running dovecot binary was deleted (stale after upgrade): {exe}"
+    )
+    expected_status_text = f"v{installed_version}"
+    assert status_text == expected_status_text or status_text.startswith(
+        f"{expected_status_text} "
+    ), (
+        f"dovecot status version mismatch: "
+        f"StatusText={status_text!r}, installed={installed_version!r}"
+    )
+
+
 def test_timezone_env(remote):
     for line in remote.iter_output("env"):
         print(line)
@@ -133,7 +169,7 @@ def test_authenticated_from(cmsetup, maildata):
 
 @pytest.mark.parametrize("from_addr", ["fake@example.org", "fake@testrun.org"])
 def test_reject_missing_dkim(cmsetup, maildata, from_addr):
-    domain = cmsetup.maildomain.strip("[").strip("]")
+    domain = cmsetup.maildomain
     sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
     sock.settimeout(10)
     try:
@@ -145,7 +181,7 @@ def test_reject_missing_dkim(cmsetup, maildata, from_addr):
     msg = maildata(
         "encrypted.eml", from_addr=from_addr, to_addr=recipient.addr
     ).as_string()
-    conn = smtplib.SMTP(cmsetup.maildomain.strip("[").strip("]"), 25, timeout=10)
+    conn = smtplib.SMTP(cmsetup.maildomain, 25, timeout=10)
     conn.starttls()
 
     with conn as s:

cmdeploy/src/cmdeploy/tests/online/test_2_deltachat.py

@@ -6,8 +6,8 @@ import imap_tools
 import pytest
 import requests
 
-from cmdeploy.remote import rshell
 from cmdeploy.cmdeploy import get_sshexec
+from cmdeploy.remote import rshell
 
 
 @pytest.fixture
@@ -15,7 +15,7 @@ def imap_mailbox(cmfactory, ssl_context):
     (ac1,) = cmfactory.get_online_accounts(1)
     user = ac1.get_config("addr")
     password = ac1.get_config("mail_pw")
-    host = user.split("@")[1].strip("[").strip("]")
+    host = user.split("@")[1]
     mailbox = imap_tools.MailBox(host, ssl_context=ssl_context)
     mailbox.login(user, password)
     mailbox.dc_ac = ac1
@@ -178,7 +178,7 @@ def test_hide_senders_ip_address(cmfactory, ssl_context):
     chat.send_text("testing submission header cleanup")
     user2.wait_for_incoming_msg()
     addr = user2.get_config("addr")
-    host = addr.split("@")[1].strip("[").strip("]")
+    host = addr.split("@")[1]
     pw = user2.get_config("mail_pw")
     mailbox = imap_tools.MailBox(host, ssl_context=ssl_context)
     mailbox.login(addr, pw)

cmdeploy/src/cmdeploy/tests/plugin.py

@@ -35,6 +35,11 @@ def pytest_runtest_setup(item):
 
 
 def _get_chatmail_config():
+    inipath = os.environ.get("CHATMAIL_INI")
+    if inipath:
+        path = Path(inipath).resolve()
+        return read_config(path), path
+
     current = Path().resolve()
     while 1:
         path = current.joinpath("chatmail.ini").resolve()
@@ -61,13 +66,8 @@ def maildomain(chatmail_config):
 
 
 @pytest.fixture(scope="session")
-def maildomain_sanitized(maildomain):
-    return maildomain.strip("[").strip("]")
-
-
-@pytest.fixture(scope="session")
-def sshdomain(maildomain_sanitized):
-    return os.environ.get("CHATMAIL_SSH", maildomain_sanitized)
+def sshdomain(maildomain):
+    return os.environ.get("CHATMAIL_SSH", maildomain)
 
 
 @pytest.fixture
@@ -80,7 +80,7 @@ def maildomain2():
 
 @pytest.fixture
 def sshdomain2(maildomain2):
-    return os.environ.get("CHATMAIL_SSH2", maildomain2.strip("[").strip("]"))
+    return os.environ.get("CHATMAIL_SSH2", maildomain2)
 
 
 def pytest_report_header():
@@ -181,14 +181,14 @@ def ssl_context(chatmail_config):
 
 
 @pytest.fixture
-def imap(maildomain_sanitized, ssl_context):
-    return ImapConn(maildomain_sanitized, ssl_context=ssl_context)
+def imap(maildomain, ssl_context):
+    return ImapConn(maildomain, ssl_context=ssl_context)
 
 
 @pytest.fixture
-def make_imap_connection(maildomain_sanitized, ssl_context):
+def make_imap_connection(maildomain, ssl_context):
     def make_imap_connection():
-        conn = ImapConn(maildomain_sanitized, ssl_context=ssl_context)
+        conn = ImapConn(maildomain, ssl_context=ssl_context)
         conn.connect()
         return conn
 
@@ -232,14 +232,14 @@ class ImapConn:
 
 
 @pytest.fixture
-def smtp(maildomain_sanitized, ssl_context):
-    return SmtpConn(maildomain_sanitized, ssl_context=ssl_context)
+def smtp(maildomain, ssl_context):
+    return SmtpConn(maildomain, ssl_context=ssl_context)
 
 
 @pytest.fixture
-def make_smtp_connection(maildomain_sanitized, ssl_context):
+def make_smtp_connection(maildomain, ssl_context):
     def make_smtp_connection():
-        conn = SmtpConn(maildomain_sanitized, ssl_context=ssl_context)
+        conn = SmtpConn(maildomain, ssl_context=ssl_context)
         conn.connect()
         return conn
 
@@ -326,8 +326,8 @@ class ChatmailACFactory:
             "password": password,
             # Setting server explicitly skips requesting autoconfig XML,
             # see https://datatracker.ietf.org/doc/draft-ietf-mailmaint-autoconfig/
-            "imapServer": domain.strip("[").strip("]"),
-            "smtpServer": domain.strip("[").strip("]"),
+            "imapServer": domain,
+            "smtpServer": domain,
         }
         if self.chatmail_config.tls_cert_mode == "self":
             transport["certificateChecks"] = "acceptInvalidCertificates"
@@ -393,12 +393,15 @@ def cmfactory(rpc, gencreds, maildomain, chatmail_config):
 
 @pytest.fixture
 def remote(sshdomain):
-    return Remote(sshdomain)
+    r = Remote(sshdomain)
+    yield r
+    r.close()
 
 
 class Remote:
     def __init__(self, sshdomain):
         self.sshdomain = sshdomain
+        self._procs = []
 
     def iter_output(self, logcmd="", ready=None):
         getjournal = "journalctl -f" if not logcmd else logcmd
@@ -408,19 +411,32 @@ class Remote:
             case "localhost": command = []
             case _: command = ["ssh", f"root@{self.sshdomain}"]
         [command.append(arg) for arg in getjournal.split()]
-        self.popen = subprocess.Popen(
+        popen = subprocess.Popen(
             command,
+            stdin=subprocess.DEVNULL,
             stdout=subprocess.PIPE,
+            stderr=subprocess.DEVNULL,
         )
-        while 1:
-            line = self.popen.stdout.readline()
-            res = line.decode().strip().lower()
-            if not res:
-                break
-            if ready is not None:
-                ready()
-                ready = None
-            yield res
+        self._procs.append(popen)
+        try:
+            while 1:
+                line = popen.stdout.readline()
+                res = line.decode().strip().lower()
+                if not res:
+                    break
+                if ready is not None:
+                    ready()
+                    ready = None
+                yield res
+        finally:
+            popen.terminate()
+            popen.wait()
+
+    def close(self):
+        while self._procs:
+            proc = self._procs.pop()
+            proc.kill()
+            proc.wait()
 
 
 @pytest.fixture
@@ -459,7 +475,7 @@ class CMSetup:
 
 class CMUser:
     def __init__(self, maildomain, addr, password, ssl_context=None):
-        self.maildomain = maildomain.strip("[").strip("]")
+        self.maildomain = maildomain
         self.addr = addr
         self.password = password
         self.ssl_context = ssl_context

cmdeploy/src/cmdeploy/tests/test_cmdeploy.py

@@ -23,15 +23,19 @@ class TestCmdline:
         run = parser.parse_args(["run"])
         assert init and run
 
-    def test_init_not_overwrite(self, capsys):
-        assert main(["init", "chat.example.org"]) == 0
+    def test_init_not_overwrite(self, capsys, tmp_path, monkeypatch):
+        monkeypatch.delenv("CHATMAIL_INI", raising=False)
+        inipath = tmp_path / "chatmail.ini"
+        args = ["init", "--config", str(inipath), "chat.example.org"]
+        assert main(args) == 0
         capsys.readouterr()
 
-        assert main(["init", "chat.example.org"]) == 1
+        assert main(args) == 1
         out, err = capsys.readouterr()
         assert "path exists" in out.lower()
 
-        assert main(["init", "chat.example.org", "--force"]) == 0
+        args.insert(1, "--force")
+        assert main(args) == 0
         out, err = capsys.readouterr()
         assert "deleting config file" in out.lower()
 

cmdeploy/src/cmdeploy/tests/test_dns.py

@@ -3,7 +3,7 @@ from copy import deepcopy
 import pytest
 
 from cmdeploy import remote
-from cmdeploy.dns import check_full_zone, check_initial_remote_data
+from cmdeploy.dns import check_full_zone, check_initial_remote_data, parse_zone_records
 
 
 @pytest.fixture
@@ -125,18 +125,49 @@ class TestPerformInitialChecks:
         assert not l
 
 
+def test_parse_zone_records():
+    text = """
+    ; This is a comment
+    some.domain. 3600 IN A 1.1.1.1
+
+    ; Another comment
+    www.some.domain. 3600 IN CNAME some.domain.
+
+    ; Multi-word rdata
+    some.domain. 3600 IN MX 10 mail.some.domain.
+
+    ; DKIM record (single line, multi-word TXT rdata)
+    dkim._domainkey.some.domain. 3600 IN TXT "v=DKIM1;k=rsa;p=MIIBIjANBgkqhkiG" "9w0BAQEFAAOCAQ8AMIIBCgKCAQEA"
+
+    ; Another TXT record
+    _dmarc.some.domain. 3600 IN TXT "v=DMARC1;p=reject"
+    """
+    records = list(parse_zone_records(text))
+    assert records == [
+        ("some.domain", "3600", "A", "1.1.1.1"),
+        ("www.some.domain", "3600", "CNAME", "some.domain."),
+        ("some.domain", "3600", "MX", "10 mail.some.domain."),
+        (
+            "dkim._domainkey.some.domain",
+            "3600",
+            "TXT",
+            '"v=DKIM1;k=rsa;p=MIIBIjANBgkqhkiG" "9w0BAQEFAAOCAQ8AMIIBCgKCAQEA"',
+        ),
+        ("_dmarc.some.domain", "3600", "TXT", '"v=DMARC1;p=reject"'),
+    ]
+
+
+def test_parse_zone_records_invalid_line():
+    text = "invalid line"
+    with pytest.raises(ValueError, match="Bad zone record line"):
+        list(parse_zone_records(text))
+
+
 def parse_zonefile_into_dict(zonefile, mockdns_base, only_required=False):
-    for zf_line in zonefile.split("\n"):
-        if zf_line.startswith("#"):
-            if "Recommended" in zf_line and only_required:
-                return
-            continue
-        if not zf_line.strip():
-            continue
-        zf_domain, zf_typ, zf_value = zf_line.split(maxsplit=2)
-        zf_domain = zf_domain.rstrip(".")
-        zf_value = zf_value.strip()
-        mockdns_base.setdefault(zf_typ, {})[zf_domain] = zf_value
+    if only_required:
+        zonefile = zonefile.split("; Recommended")[0]
+    for name, ttl, rtype, rdata in parse_zone_records(zonefile):
+        mockdns_base.setdefault(rtype, {})[name] = rdata
 
 
 class MockSSHExec:

cmdeploy/src/cmdeploy/tests/test_dovecot_deployer.py

@@ -0,0 +1,238 @@
+from contextlib import nullcontext
+from types import SimpleNamespace
+
+import pytest
+
+from cmdeploy.dovecot import deployer as dovecot_deployer
+from pyinfra.facts.deb import DebPackages
+
+
+def make_host(*fact_pairs):
+    """Build a mock host; get_fact(cls) dispatches to the provided facts mapping.
+
+    Args:
+        *fact_pairs: tuples of (fact_class, fact_value) to register
+
+    Returns:
+        SimpleNamespace with get_fact that raises a clear error if an
+        unexpected fact type is requested.
+    """
+    facts = dict(fact_pairs)
+
+    def get_fact(cls):
+        if cls not in facts:
+            registered = ", ".join(c.__name__ for c in facts)
+            raise LookupError(
+                f"unexpected get_fact({cls.__name__}); "
+                f"only registered: {registered}"
+            )
+        return facts[cls]
+
+    return SimpleNamespace(get_fact=get_fact)
+
+
+@pytest.fixture
+def deployer():
+    return dovecot_deployer.DovecotDeployer(
+        SimpleNamespace(mail_domain="chat.example.org"),
+        disable_mail=False,
+    )
+
+
+@pytest.fixture
+def patch_blocked(monkeypatch):
+    monkeypatch.setattr(dovecot_deployer, "blocked_service_startup", nullcontext)
+
+
+@pytest.fixture
+def mock_files_put(monkeypatch):
+    monkeypatch.setattr(
+        dovecot_deployer.files,
+        "put",
+        lambda **kwargs: SimpleNamespace(changed=False),
+    )
+
+
+@pytest.fixture
+def track_shell(monkeypatch):
+    calls = []
+    monkeypatch.setattr(
+        dovecot_deployer.server,
+        "shell",
+        lambda **kwargs: calls.append(kwargs) or SimpleNamespace(changed=False),
+    )
+    return calls
+
+
+def test_download_dovecot_package_skips_epoch_matched_install(monkeypatch):
+    epoch_version = dovecot_deployer.DOVECOT_PACKAGE_VERSION
+    downloads = []
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "host",
+        make_host((DebPackages, {"dovecot-core": [epoch_version]})),
+    )
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "_pick_url",
+        lambda primary, fallback: primary,
+    )
+    monkeypatch.setattr(
+        dovecot_deployer.files,
+        "download",
+        lambda **kwargs: downloads.append(kwargs),
+    )
+
+    deb, changed = dovecot_deployer._download_dovecot_package("core", "amd64")
+
+    assert deb is None, f"expected no deb path when version matches, got {deb!r}"
+    assert changed is False, "should not flag changed when version already installed"
+    assert downloads == [], "should not download when version already installed"
+
+
+def test_download_dovecot_package_uses_archive_version_for_url_and_filename(
+    monkeypatch,
+):
+    downloads = []
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "host",
+        make_host((DebPackages, {})),
+    )
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "_pick_url",
+        lambda primary, fallback: primary,
+    )
+    monkeypatch.setattr(
+        dovecot_deployer.files,
+        "download",
+        lambda **kwargs: downloads.append(kwargs),
+    )
+
+    deb, changed = dovecot_deployer._download_dovecot_package("core", "amd64")
+
+    archive_version = dovecot_deployer.DOVECOT_ARCHIVE_VERSION.replace("+", "%2B")
+    expected_deb = f"/root/dovecot-core_{archive_version}_amd64.deb"
+
+    # Verify the returned path uses archive version, not package version (with epoch)
+    assert changed is True, "should flag changed when package not yet installed"
+    assert deb == expected_deb, f"deb path mismatch: {deb!r} != {expected_deb!r}"
+    assert dovecot_deployer.DOVECOT_PACKAGE_VERSION not in deb, (
+        f"deb path should use archive version (no epoch), got {deb!r}"
+    )
+    assert len(downloads) == 1, "files.download should be called exactly once"
+
+
+def test_install_skips_dpkg_path_when_epoch_matched_packages_present(
+    deployer, patch_blocked, mock_files_put, track_shell, monkeypatch
+):
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "host",
+        make_host(
+            (
+                dovecot_deployer.DebPackages,
+                {
+                    "dovecot-core": [dovecot_deployer.DOVECOT_PACKAGE_VERSION],
+                    "dovecot-imapd": [dovecot_deployer.DOVECOT_PACKAGE_VERSION],
+                    "dovecot-lmtpd": [dovecot_deployer.DOVECOT_PACKAGE_VERSION],
+                },
+            ),
+            (dovecot_deployer.Arch, "x86_64"),
+        ),
+    )
+    downloads = []
+    monkeypatch.setattr(
+        dovecot_deployer.files,
+        "download",
+        lambda **kwargs: downloads.append(kwargs),
+    )
+
+    deployer.install()
+
+    assert downloads == [], "should not download when all packages epoch-matched"
+    assert track_shell == [], "should not run dpkg when all packages epoch-matched"
+    assert deployer.need_restart is False, (
+        "need_restart should be False when nothing changed"
+    )
+
+
+def test_install_unsupported_arch_falls_back_to_apt(
+    deployer, patch_blocked, mock_files_put, track_shell, monkeypatch
+):
+    # For unsupported architectures, all fact lookups return the arch string.
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "host",
+        SimpleNamespace(get_fact=lambda cls: "riscv64"),
+    )
+    apt_calls = []
+
+    # Mirrors apt.packages() return value: OperationMeta with .changed property.
+    # Only lmtpd triggers a change to verify |= accumulation of changed flags.
+    def fake_apt(**kwargs):
+        apt_calls.append(kwargs)
+        changed = "lmtpd" in kwargs["packages"][0]
+        return SimpleNamespace(changed=changed)
+
+    monkeypatch.setattr(dovecot_deployer.apt, "packages", fake_apt)
+
+    deployer.install()
+
+    actual_pkgs = [c["packages"] for c in apt_calls]
+    assert actual_pkgs == [["dovecot-core"], ["dovecot-imapd"], ["dovecot-lmtpd"]], (
+        f"expected apt install of core/imapd/lmtpd, got {actual_pkgs}"
+    )
+    assert track_shell == [], "should not run dpkg for unsupported arch"
+    assert deployer.need_restart is True, (
+        "need_restart should be True when apt installed a package"
+    )
+
+
+def test_install_runs_dpkg_when_packages_need_download(
+    deployer, patch_blocked, mock_files_put, track_shell, monkeypatch
+):
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "host",
+        make_host(
+            (dovecot_deployer.DebPackages, {}),
+            (dovecot_deployer.Arch, "x86_64"),
+        ),
+    )
+    monkeypatch.setattr(
+        dovecot_deployer,
+        "_pick_url",
+        lambda primary, fallback: primary,
+    )
+    monkeypatch.setattr(
+        dovecot_deployer.files,
+        "download",
+        lambda **kwargs: SimpleNamespace(changed=True),
+    )
+
+    deployer.install()
+
+    assert len(track_shell) == 1, (
+        f"expected one server.shell() call for dpkg install, got {len(track_shell)}"
+    )
+    cmds = track_shell[0]["commands"]
+    assert len(cmds) == 3, f"expected 3 dpkg/apt commands, got: {cmds}"
+    assert cmds[0].startswith("dpkg --force-confdef --force-confold -i ")
+    assert "apt-get -y --fix-broken install" in cmds[1]
+    assert cmds[2].startswith("dpkg --force-confdef --force-confold -i ")
+    assert deployer.need_restart is True, (
+        "need_restart should be True after dpkg install"
+    )
+
+
+def test_pick_url_falls_back_on_primary_error(monkeypatch):
+    def raise_error(req, timeout):
+        raise OSError("connection timeout")
+
+    monkeypatch.setattr(dovecot_deployer.urllib.request, "urlopen", raise_error)
+    result = dovecot_deployer._pick_url("http://primary", "http://fallback")
+    assert result == "http://fallback", (
+        f"should fall back when primary fails, got {result!r}"
+    )

doc/source/getting_started.rst

@@ -98,6 +98,13 @@ steps. Please substitute it with your own domain.
    configure at your DNS provider (it can take some time until they are
    public).
 
+Docker installation
+-------------------
+
+There is experimental support for running chatmail via Docker Compose.
+See the `chatmail/docker README <https://github.com/chatmail/docker>`_
+for full setup instructions.
+
 Other helpful commands
 ----------------------