cmdeploy: enable running DNS commands on localhost

cmdeploy/src/cmdeploy/cmdeploy.py

@@ -72,7 +72,7 @@ def run_cmd_options(parser):
     parser.add_argument(
         "--ssh-host",
         dest="ssh_host",
-        help="specify an SSH host to deploy to; uses mail_domain from chatmail.ini by default",
+        help="Deploy to 'localhost', via 'docker', or to a specific SSH host",
     )
     parser.add_argument(
         "--skip-dns-check",
@@ -135,6 +135,11 @@ def dns_cmd_options(parser):
         default=None,
         help="write out a zonefile",
     )
+    parser.add_argument(
+        "--ssh-host",
+        dest="ssh_host",
+        help="Run the DNS queries on 'localhost', in the chatmail 'docker' container, or on a specific SSH host",
+    )
 
 
 def dns_cmd(args, out):

cmdeploy/src/cmdeploy/dns.py

@@ -10,7 +10,7 @@ def get_initial_remote_data(sshexec, mail_domain):
     if sshexec == "docker":
         return remote.rdns.perform_initial_checks(mail_domain, pre_command="docker exec chatmail ")
     elif sshexec == "localhost":
-        return remote.rdns.perform_initial_checks(mail_domain, pre_command="running on localhost")
+        return remote.rdns.perform_initial_checks(mail_domain, pre_command="")
     return sshexec.logged(
         call=remote.rdns.perform_initial_checks, kwargs=dict(mail_domain=mail_domain)
     )

cmdeploy/src/cmdeploy/remote/rdns.py

@@ -26,9 +26,6 @@ def perform_initial_checks(mail_domain, pre_command=""):
     WWW = query_dns("CNAME", f"www.{mail_domain}")
 
     res = dict(mail_domain=mail_domain, A=A, AAAA=AAAA, MTA_STS=MTA_STS, WWW=WWW)
-    if pre_command == "running on localhost":
-        return res
-
     res["acme_account_url"] = shell(pre_command + "acmetool account-url", fail_ok=True)
     res["dkim_entry"], res["web_dkim_entry"] = get_dkim_entry(
         mail_domain, pre_command, dkim_selector="opendkim"

docs/DOCKER_INSTALLATION_EN.md

@@ -96,6 +96,11 @@ docker compose logs -f chatmail # view container logs, press CTRL+C to exit
 
 8. After installation is complete, you can open `https://<your_domain_name>` in your browser.
 
+9. To send messages to other chatmail relays,
+   you need to set additional DNS records.
+   Run `docker exec chatmail scripts/cmdeploy.sh dns --ssh-host localhost`
+   to see recommended DNS records and check whether they are correct.
+
 ## Using custom files
 
 When using Docker, you can apply modified configuration files to make the installation more personalized. This is usually needed for the `www/src` section so that the Chatmail landing page is customized to your taste, but it can be used for any other cases as well.