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Author SHA1 Message Date
Jagoda Ślązak 29204a73f1 chore(deps): Upgrade filtermail to v0.7.3
## 0.7.3 - 2026-06-27

### Features

- *(transport)* Worker eviction
## 0.7.2 - 2026-06-26

### Documentation

- *(readme)* Disable colors in mermaid diagrams
- *(readme)* Update Transport mode doc

### Features

- *(transport)* Destination worker pool

### Refactor

- Implement Display for AddressDomain

### Testing

- Test filtermail-transport

Signed-off-by: Jagoda Ślązak <jslazak@jslazak.com>
2026-06-29 07:04:19 +02:00
27 changed files with 25 additions and 381 deletions
-2
View File
@@ -20,8 +20,6 @@ concurrency:
jobs:
no-dns:
name: LXC deploy and test
permissions:
contents: read
uses: chatmail/cmlxc/.github/workflows/lxc-test.yml@main
with:
cmlxc_version: main
+1 -3
View File
@@ -29,7 +29,7 @@ jobs:
ref: ${{ github.event.pull_request.head.sha }}
persist-credentials: false
- name: download filtermail
run: curl -L https://github.com/chatmail/filtermail/releases/download/v0.7.4/filtermail-x86_64 -o /usr/local/bin/filtermail && chmod +x /usr/local/bin/filtermail
run: curl -L https://github.com/chatmail/filtermail/releases/download/v0.7.3/filtermail-x86_64 -o /usr/local/bin/filtermail && chmod +x /usr/local/bin/filtermail
- name: run chatmaild tests
working-directory: chatmaild
run: pipx run tox
@@ -57,8 +57,6 @@ jobs:
lxc-test:
name: LXC deploy and test
permissions:
contents: read
uses: chatmail/cmlxc/.github/workflows/lxc-test.yml@main
with:
cmlxc_version: main
+1 -1
View File
@@ -51,7 +51,7 @@ jobs:
mkdir -p "$HOME/.ssh"
echo "${{ secrets.CHATMAIL_STAGING_SSHKEY }}" > "$HOME/.ssh/key"
chmod 600 "$HOME/.ssh/key"
rsync -rILvh -e "ssh -i $HOME/.ssh/key -o StrictHostKeyChecking=no" $GITHUB_WORKSPACE/doc/build/ "${{ secrets.USERNAME }}@chatmail.at:${STEPS_PREPARE_OUTPUTS_PRID}/"
rsync -rILvh -e "ssh -i $HOME/.ssh/key -o StrictHostKeyChecking=no" $GITHUB_WORKSPACE/doc/build/ "${{ secrets.USERNAME }}@chatmail.at:/var/www/html/staging.chatmail.at/doc/relay/${STEPS_PREPARE_OUTPUTS_PRID}/"
env:
STEPS_PREPARE_OUTPUTS_PRID: ${{ steps.prepare.outputs.prid }}
+2 -2
View File
@@ -1,7 +1,7 @@
# Chatmail relays for end-to-end encrypted email
Chatmail relay servers are interoperable Mail Transport Agents (MTAs) designed for:
Chatmail relay servers are interoperable Mail Transport Agents (MTAs) designed for:
- **Zero State:** no private data or metadata collected, messages are auto-deleted, low disk usage
@@ -18,7 +18,7 @@ Chatmail relay servers are interoperable Mail Transport Agents (MTAs) designed f
- **Reliable Federation and Decentralization:** No spam or IP reputation checks, federating
depends on established IETF standards and protocols.
This repository contains everything needed to setup a ready-to-use chatmail relay on an ssh-reachable host.
This repository contains everything needed to setup a ready-to-use chatmail relay on an ssh-reachable host.
For getting started and more information please refer to the web version of this repositories' documentation at
[https://chatmail.at/doc/relay](https://chatmail.at/doc/relay)
-1
View File
@@ -8,7 +8,6 @@ version = "0.3"
dependencies = [
"iniconfig",
"filelock",
"psutil",
"requests",
"crypt-r >= 3.13.1 ; python_version >= '3.13'",
]
-10
View File
@@ -75,16 +75,6 @@ class Config:
self.privacy_pdo = params.pop("privacy_pdo", None)
self.privacy_supervisor = params.pop("privacy_supervisor", None)
self.max_load_1m = float(params.pop("max_load_1m", 5))
self.min_available_memory_mb = parse_size_mb(
params.pop("min_available_memory", "200M")
)
self.min_free_disk_space_mb = parse_size_mb(
params.pop("min_free_disk_space", "1G")
)
self.max_imap_connections = int(params.pop("max_imap_connections", 10000))
self.max_smtp_connections = int(params.pop("max_smtp_connections", 1000))
# TLS certificate management.
# If tls_external_cert_and_key is set, use externally managed certs.
# Otherwise derived from the domain name:
-3
View File
@@ -14,7 +14,6 @@ except ImportError:
from .config import Config, read_config
from .dictproxy import DictProxy
from .migrate_db import migrate_from_db_to_maildir
from .syslimits import has_sufficient_resources
NOCREATE_FILE = "/etc/chatmail-nocreate"
VALID_LOCALPART_RE = re.compile(r"^[a-z0-9._-]+$")
@@ -148,8 +147,6 @@ class AuthDictProxy(DictProxy):
return userdata
if not is_allowed_to_create(self.config, addr, cleartext_password):
return
if not has_sufficient_resources(self.config):
return
lock = filelock.FileLock(str(user.password_path) + ".lock", timeout=5)
with lock:
@@ -42,33 +42,6 @@ mail_domain = {mail_domain}
# minimum length a password must have
#password_min_length = 9
#
# System resource limits
#
# The following three limits refuse creation of new addresses
# while existing addresses keep working.
# Rejections are logged by the doveauth service.
# Maximum 1-minute load average, as reported by "uptime";
# it counts processes waiting for disk I/O as well as for CPU.
#max_load_1m = 5
# Minimum memory available without swapping.
#min_available_memory = 200M
# Minimum free disk space on the file system holding the mailboxes.
#min_free_disk_space = 1G
# Maximum number of concurrent IMAP connections
# (the Dovecot imap process limit).
#max_imap_connections = 10000
# Maximum number of concurrent SMTP connections
# on each of the submission and smtps ports (the Postfix process limit).
# A single client IP may use up to a fifth of this.
#max_smtp_connections = 1000
# Use externally managed TLS certificates instead of built-in acmetool.
# Paths refer to files on the deployment server (not the build machine).
# Both files must already exist before running cmdeploy.
-32
View File
@@ -1,32 +0,0 @@
"""Detect whether the system is at its limits."""
import logging
import psutil
MB = 1024 * 1024
def read_value(getter):
try:
return getter()
except Exception as e:
logging.warning("ignoring unreadable system limit: %s", e)
return None
def has_sufficient_resources(config):
"""Return False if load, memory or disk exceeds a configured limit."""
load = read_value(lambda: psutil.getloadavg()[0])
mem = read_value(lambda: psutil.virtual_memory().available // MB)
disk = read_value(lambda: psutil.disk_usage(str(config.mailboxes_dir)).free // MB)
if load is not None and load > config.max_load_1m:
msg = f"load avg {load:.2f} > {config.max_load_1m:.2f}"
elif mem is not None and mem < config.min_available_memory_mb:
msg = f"available memory {mem}MB < {config.min_available_memory_mb}MB"
elif disk is not None and disk < config.min_free_disk_space_mb:
msg = f"free disk {disk}MB < {config.min_free_disk_space_mb}MB"
else:
return True
logging.warning("registration rejected: %s", msg)
return False
-4
View File
@@ -20,10 +20,6 @@ def make_config(tmp_path):
basedir.mkdir(parents=True, exist_ok=True)
overrides = settings.copy() if settings else {}
overrides["mailboxes_dir"] = str(basedir)
# permissive resource limits so tests never depend on host load/memory/disk
overrides.setdefault("max_load_1m", "99999")
overrides.setdefault("min_available_memory", "0")
overrides.setdefault("min_free_disk_space", "0")
write_initial_config(inipath, mail_domain, overrides=overrides)
return read_config(inipath)
@@ -45,8 +45,6 @@ def test_read_config_basic_using_defaults(tmp_path, maildomain):
assert example_config.username_min_length == 9
assert example_config.username_max_length == 9
assert example_config.password_min_length == 9
assert example_config.max_imap_connections == 10000
assert example_config.max_smtp_connections == 1000
assert example_config._unused_keys == []
@@ -202,17 +202,3 @@ def test_50_concurrent_lookups_different_accounts(gencreds, dictproxy):
res = results.get()
if res is not None:
pytest.fail(f"concurrent lookup failed\n{res}")
def test_insufficient_resources_block_creation_not_existing_logins(
dictproxy, gencreds, monkeypatch
):
addr, password = gencreds()
assert dictproxy.lookup_passdb(addr, password)
monkeypatch.setattr(
chatmaild.doveauth, "has_sufficient_resources", lambda config: False
)
newaddr, newpassword = gencreds()
assert not dictproxy.lookup_passdb(newaddr, newpassword)
assert dictproxy.lookup_passdb(addr, password)
@@ -1,45 +0,0 @@
import shutil
import psutil
from chatmaild.syslimits import has_sufficient_resources
PERMISSIVE = {
"max_load_1m": "99999",
"min_available_memory": "0",
"min_free_disk_space": "0",
}
def test_rejects_constrained_system(make_config, caplog):
assert has_sufficient_resources(make_config("chat.example.org", PERMISSIVE))
for settings in (
{"max_load_1m": "-1.0"},
{"min_available_memory": "99999999G"},
{"min_free_disk_space": "99999999G"},
):
config = make_config("chat.example.org", PERMISSIVE | settings)
caplog.clear()
assert not has_sufficient_resources(config), settings
assert "registration rejected" in caplog.text
def test_unreadable_disk_does_not_reject(make_config, caplog):
config = make_config(
"chat.example.org", PERMISSIVE | {"min_free_disk_space": "99999999G"}
)
shutil.rmtree(config.mailboxes_dir)
assert has_sufficient_resources(config)
assert "ignoring" in caplog.text
def test_one_unreadable_value_keeps_other_checks(make_config, monkeypatch, caplog):
def raise_error(*args):
raise psutil.Error("dud")
monkeypatch.setattr(psutil, "getloadavg", raise_error)
config = make_config(
"chat.example.org", PERMISSIVE | {"min_free_disk_space": "99999999G"}
)
assert not has_sufficient_resources(config)
assert "ignoring" in caplog.text
@@ -1,2 +1,2 @@
"acme-enter-email": "{{ email }}"
"acme-agreement:https://letsencrypt.org/documents/LE-SA-v1.8-July-06-2026.pdf": true
"acme-agreement:https://letsencrypt.org/documents/LE-SA-v1.7-June-04-2026.pdf": true
+7 -25
View File
@@ -32,7 +32,6 @@ from .external.deployer import ExternalTlsDeployer
from .filtermail.deployer import FiltermailDeployer
from .mtail.deployer import MtailDeployer
from .nginx.deployer import NginxDeployer
from .websockify.deployer import WebsockifyDeployer
from .opendkim.deployer import OpendkimDeployer
from .postfix.deployer import PostfixDeployer
from .selfsigned.deployer import SelfSignedTlsDeployer
@@ -139,22 +138,9 @@ class UnboundDeployer(Deployer):
# 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():
# dns-root-data is an optional package
# that contains /usr/share/dns/root.key
#
# This file is copied into /var/lib/unbound/root.key
# at the start of "unbound" systemd unit
# by /usr/libexec/unbound-helper shell script
# from the "unbound" package as of version 1.17.1-2+deb12u4
#
# The same /var/lib/unbound/root.key can be retrieved directly
# following the procedure from
# <https://www.rfc-editor.org/info/rfc7958/#section-3.1>
# with "unbound-anchor -a /var/lib/unbound/root.key"
# We don't install and use "unbound-anchor".
apt.packages(
name="Install unbound",
packages=["unbound", "dns-root-data", "dnsutils"],
packages=["unbound", "unbound-anchor", "dnsutils"],
)
def configure(self):
@@ -180,6 +166,12 @@ class UnboundDeployer(Deployer):
dest="/etc/resolv.conf",
force=True,
)
server.shell(
name="Generate root keys for validating DNSSEC",
commands=[
"unbound-anchor -a /var/lib/unbound/root.key || true",
],
)
self.ensure_directory(
path="/etc/unbound/unbound.conf.d",
)
@@ -254,13 +246,6 @@ class LegacyRemoveDeployer(Deployer):
def install(self):
apt.packages(name="Remove rspamd", packages="rspamd", present=False)
# unbound-anchor was used to download /var/lib/unbound/root.key
# It is replaced by dns-root-data which contains /usr/share/dns/root.key.
# unbound systemd unit copies /usr/share/dns/root.key
# into /var/lib/unbound/root.key automatically on start
# as long as /usr/share/dns/root.key is present.
apt.packages(name="Remove unbound-anchor", packages="unbound-anchor", present=False)
# remove historic expunge script
# which is now implemented through a systemd timer (chatmail-expire)
self.remove_file("/etc/cron.d/expunge")
@@ -371,8 +356,6 @@ class ChatmailVenvDeployer(Deployer):
def __init__(self, config):
self.config = config
self.units = (
# doveauth must restart when chatmaild/ini file changes
"doveauth",
"chatmail-metadata",
"lastlogin",
"chatmail-expire",
@@ -566,7 +549,6 @@ def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -
PostfixDeployer(config, disable_mail),
FcgiwrapDeployer(),
NginxDeployer(config),
WebsockifyDeployer(config),
MtailDeployer(config.mtail_address),
GithashDeployer(),
]
+1 -1
View File
@@ -34,7 +34,7 @@ class DovecotDeployer(Deployer):
def __init__(self, config, disable_mail):
self.config = config
self.disable_mail = disable_mail
self.units = []
self.units = ["doveauth"]
def install(self):
arch = host.get_fact(Arch)
@@ -37,15 +37,11 @@ default_client_limit = 20000
# the following warning will be logged:
# Warning: service(imap): process_limit (1024) reached, client connections are being dropped
service imap {
process_limit = {{ config.max_imap_connections }}
process_limit = 50000
}
{% if config.privacy_mail %}
# Advertised to clients as IMAP METADATA /shared/admin (RFC 5464).
# The privacy_mail contact from chatmail.ini is used because it is
# the only address set by an operator.
mail_server_admin = mailto:{{ config.privacy_mail }}
{% endif %}
mail_server_admin = mailto:root@{{ config.mail_domain }}
mail_server_comment = Chatmail server
# `zlib` enables compressing messages stored in the maildir.
# See
+3 -3
View File
@@ -20,10 +20,10 @@ class FiltermailDeployer(Deployer):
return
arch = host.get_fact(facts.server.Arch)
url = f"https://github.com/chatmail/filtermail/releases/download/v0.7.4/filtermail-{arch}"
url = f"https://github.com/chatmail/filtermail/releases/download/v0.7.3/filtermail-{arch}"
sha256sum = {
"x86_64": "484cb8dff083134aefba9fce4a6b7ef4784a0f0e28e5108ecf8bb9e58a44fd2c",
"aarch64": "66aa0ca2ca9add7a12d92883d76f8786384092adfde24a3d3a1d0b1f30d23a9e",
"x86_64": "bd4be15b27199909a44499cacf23e634249219f8cd715e5ce707de7eb711d7d9",
"aarch64": "a13038b5ca421c3b2c4c4aa50dbc3c8c4de6f9aaa877a05c0ec978b131550c6b",
}[arch]
self.download_executable(url, self.bin_path, sha256sum)
@@ -28,13 +28,6 @@ counter created_nonci_accounts
}
}
# doveauth refusing new addresses because a chatmail.ini
# system resource limit is exceeded.
counter rejected_registrations
/registration rejected: / {
rejected_registrations++
}
counter postfix_timeouts
/timeout after DATA/ {
postfix_timeouts++
@@ -80,11 +73,6 @@ counter incoming_unencrypted_mail_count
filtered_incoming_mail_count++
}
counter incoming_mailer_daemon_mail_count
/Incoming: Filtering mailer-daemon message from/ {
incoming_mailer_daemon_mail_count++
filtered_incoming_mail_count++
}
counter rejected_unencrypted_mail_count
/Rejected unencrypted mail/ {
+1 -18
View File
@@ -128,10 +128,7 @@ http {
proxy_set_header Connection "upgrade";
}
# Endpoints Iroh uses for net_report probes and that clients
# probe to tell whether this relay works. Both paths are served
# by iroh-relay 0.35 and by the 1.0 line.
location /ping {
location /relay/probe {
proxy_pass http://127.0.0.1:3340;
proxy_http_version 1.1;
}
@@ -140,20 +137,6 @@ http {
proxy_pass http://127.0.0.1:3340;
proxy_http_version 1.1;
}
location /imap {
proxy_pass http://127.0.0.1:8143;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
}
location /smtp {
proxy_pass http://127.0.0.1:8587;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "upgrade";
}
}
# Redirect www. to non-www
-8
View File
@@ -85,14 +85,6 @@ inet_protocols = all
lmtp_header_checks = regexp:/etc/postfix/lmtp_header_cleanup
# Do not apply header checks to MIME headers
# and other headers that are actually part of the message body.
# Reference:
# <https://www.postfix.org/postconf.5.html#disable_mime_input_processing>
# <https://www.postfix.org/header_checks.5.html>
# <https://stump.io/blog/2020/11/29/a-little-gotcha-with-postfixs-header_checks/>
disable_mime_input_processing = yes
mua_client_restrictions = permit_sasl_authenticated, reject
mua_sender_restrictions = reject_sender_login_mismatch, permit_sasl_authenticated, reject
mua_helo_restrictions = permit_mynetworks, reject_invalid_helo_hostname, reject_non_fqdn_helo_hostname, permit
+5 -4
View File
@@ -18,7 +18,7 @@ smtp inet n - y - - smtpd
-o smtpd_tls_mandatory_protocols=>=TLSv1.2
-o smtpd_proxy_filter=127.0.0.1:{{ config.filtermail_smtp_port_incoming }}
-o smtpd_relay_restrictions=reject_unauth_destination
submission inet n - y - {{ config.max_smtp_connections }} smtpd
submission inet n - y - 5000 smtpd
-o syslog_name=postfix/submission
-o smtpd_tls_security_level=encrypt
-o smtpd_tls_mandatory_protocols=>=TLSv1.3
@@ -32,9 +32,9 @@ submission inet n - y - {{ config.max_smtp_connections }
-o smtpd_sender_restrictions=$mua_sender_restrictions
-o smtpd_recipient_restrictions=
-o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-o smtpd_client_connection_count_limit={{ config.max_smtp_connections // 5 }}
-o smtpd_client_connection_count_limit=1000
-o smtpd_proxy_filter=127.0.0.1:{{ config.filtermail_smtp_port }}
smtps inet n - y - {{ config.max_smtp_connections }} smtpd
smtps inet n - y - 5000 smtpd
-o syslog_name=postfix/smtps
-o smtpd_tls_wrappermode=yes
-o smtpd_tls_security_level=encrypt
@@ -48,7 +48,7 @@ smtps inet n - y - {{ config.max_smtp_connections }
-o smtpd_sender_restrictions=$mua_sender_restrictions
-o smtpd_recipient_restrictions=
-o smtpd_relay_restrictions=permit_sasl_authenticated,reject
-o smtpd_client_connection_count_limit={{ config.max_smtp_connections // 5 }}
-o smtpd_client_connection_count_limit=1000
-o smtpd_proxy_filter=127.0.0.1:{{ config.filtermail_smtp_port }}
#628 inet n - y - - qmqpd
pickup unix n - y 60 1 pickup
@@ -76,6 +76,7 @@ lmtp unix - - y - - lmtp
anvil unix - - y - 1 anvil
scache unix - - y - 1 scache
postlog unix-dgram n - n - 1 postlogd
filter unix - n n - - lmtp
# Local SMTP server for reinjecting outgoing filtered mail.
127.0.0.1:{{ config.postfix_reinject_port }} inet n - n - 100 smtpd
-o syslog_name=postfix/reinject
@@ -1,19 +0,0 @@
from pyinfra.operations import apt, server
from cmdeploy.basedeploy import Deployer
class WebsockifyDeployer(Deployer):
def __init__(self, config):
self.config = config
def install(self):
apt.packages(name="Install websockify", packages=["websockify"])
def configure(self):
self.ensure_systemd_unit("websockify/websockify-imap.service")
self.ensure_systemd_unit("websockify/websockify-submission.service")
def activate(self):
self.ensure_service("websockify-imap.service")
self.ensure_service("websockify-submission.service")
@@ -1,12 +0,0 @@
[Unit]
Description=WebSocket proxy for IMAP
After=network.target
[Service]
Type=simple
Restart=always
ExecStart=/usr/bin/websockify 127.0.0.1:8143 localhost:143
DynamicUser=true
[Install]
WantedBy=multi-user.target
@@ -1,12 +0,0 @@
[Unit]
Description=WebSocket proxy for SMTP
After=network.target
[Service]
Type=simple
Restart=always
ExecStart=/usr/bin/websockify 127.0.0.1:8587 localhost:587
DynamicUser=true
[Install]
WantedBy=multi-user.target
-87
View File
@@ -199,93 +199,6 @@ creating addresses, login with ssh to the deployment machine and run:
Chatmail address creation will be denied while this file is present.
.. _system-limits:
Configurable System Limits
--------------------------
Limits for auto-rejecting address creation
..........................................
A relay refuses creation of new addresses
when the machine runs low on resources,
but existing addresses keep working.
Three ``chatmail.ini`` settings control this,
shown here with their defaults::
max_load_1m = 5
min_available_memory = 200M
min_free_disk_space = 1G
- ``max_load_1m`` is the maximum 1-minute load average,
as reported by ``uptime``;
it counts processes waiting for disk I/O as well as for CPU.
It is deliberately not scaled by the number of CPUs
because I/O rather than CPU is what typically limits a relay.
- ``min_available_memory`` is the minimum memory available without swapping.
- ``min_free_disk_space`` is the minimum free disk space
on the file system holding the mailboxes.
The defaults suit the small machine described in
`Minimal requirements and prerequisites`_.
.. note::
If you run a bigger machine,
raise ``max_load_1m`` after watching ``uptime`` under typical load.
Rejections are logged by the ``doveauth`` service,
so you can check whether a limit is set too tightly::
journalctl -u doveauth --grep 'registration rejected'
If ``mtail_address`` is set, rejections are also counted
in the ``rejected_registrations`` metric.
Overall IMAP and SMTP connection limits
.......................................
Two further settings bound how many connections
the relay accepts at all, again shown with their defaults::
max_imap_connections = 10000
max_smtp_connections = 1000
``max_imap_connections`` becomes the Dovecot imap process limit,
and ``max_smtp_connections`` the Postfix process limit
on each of the submission and smtps ports.
A single client IP may use up to a fifth of ``max_smtp_connections``.
Each connection costs memory,
so these limits defend the relay against running out of RAM.
Unless ``imap_compress`` is enabled,
an IMAP connection that is idle for ``imap_hibernate_timeout``
is handed over to the ``imap-hibernate`` process
and does not count towards ``max_imap_connections``,
which is why a relay can serve far more IMAP clients
than this setting suggests.
If you run a large relay with 10k or 100k's of addresses,
check current connection counts before upgrading
and set the limits accordingly.
To see how close a running relay is to these two limits,
copy ``scripts/check-connections.sh`` from the relay repository
onto the relay and run it there::
imap 5 ports 143,993 (max_imap_connections)
5 dovecot sessions, 0 of them in an active imap process
submission 0 ports 465,587 (max_smtp_connections per port)
incoming 0 port 25 (from other relays, no chatmail.ini limit)
It counts established sockets with ``ss``
and cross-checks the IMAP number against ``doveadm who``.
Running a relay with self-signed certificates
----------------------------------------------
-26
View File
@@ -1,26 +0,0 @@
#!/bin/bash
#
# Show current IMAP and SMTP connections on a chatmail relay,
# to compare against the max_imap_connections and max_smtp_connections
# settings in chatmail.ini. Run this on the relay itself.
set -e
# Count established TCP connections whose local port is one of the arguments.
established() {
filter=$(printf 'sport = :%s or ' "$@")
ss -Htn state established "( ${filter% or } )" | wc -l
}
# doveadm prints a header line and then one line per logged-in user,
# with that user's number of connections in the second column.
sessions=$(doveadm who | awk 'NR > 1 { n += $2 } END { print n + 0 }')
# Unless imap_compress is enabled, connections idle for
# imap_hibernate_timeout are handed over to the imap-hibernate
# process, so they cost no imap process while idle.
active=$(pgrep -x imap | wc -l)
printf 'imap %6d ports 143,993 (max_imap_connections)\n' "$(established 143 993)"
printf ' %6d dovecot sessions, %d of them in an active imap process\n' "$sessions" "$active"
printf 'submission %6d ports 465,587 (max_smtp_connections per port)\n' "$(established 465 587)"
printf 'incoming %6d port 25 (from other relays, no chatmail.ini limit)\n' "$(established 25)"