[Bug 1957104] Re: updating openssh-server fails, because port 22 is in use by systemd

[Athos Ribeiro]

Hi Thomas,

Thank you for taking the time to file a bug report.

The systemd service is indeed restarted throughout the package upgrade
process. This means that sshd is supposed to halt (and cease listening
on port 22) before the service is started again.

How are you starting the ssh server? Would you mind providing your
configuration file as well (make sure there is no sensitive data being
shared if you decide to do so). Providing logs will also help us
identify the issue you have been experiencing.

As for the second issue reported, regarding creation of the /run/sshd
directory when starting the service through systemd, this is actually
performed through the RuntimeDirectory directive in the ssh unit files.

Finally, would you be able to provide a reproducer for the issue?

Since there is not enough information in your report to begin triage or to
differentiate between a local configuration problem and a bug in Ubuntu, I
am marking this bug as "Incomplete". We would be grateful if you would:
provide a more complete description of the problem, explain why you
believe this is a bug in Ubuntu rather than a problem specific to your
system, and then change the bug status back to "New".

For local configuration issues, you can find assistance here:
http://www.ubuntu.com/support/community

** Changed in: openssh (Ubuntu)
       Status: New => Incomplete

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to openssh in Ubuntu.
https://bugs.launchpad.net/bugs/1957104

Title:
  updating openssh-server fails, because port 22 is in use by systemd

Status in openssh package in Ubuntu:
  Incomplete

Bug description:
  openssh-server tries to restart itself, but openssh-server reports
  port 22 in use. This is true: systemd has taken port 22 to start sshd
  if one connects to port 22.

  two solutions:
  1. dont start sshd after installing.
     configure it without starting it afterwards.
  2. stop systemd listening on port 22
     before starting sshd, then start sshd,
     terminate it after configuring, then
     start systemd listening on port 22 again.

  Second problem:
  starting ssh.service does not check if "/run/sshd" exists. This directory has to be created before sshd is started. Unclear if this is an error with sshd not creating this directory before dropping privileges or if this has to be done once while installing. IMHO the first is the case.

  
  Workaround:
  systemctl stop ssh.service
  systemctl disable ssh.service
  apt upgrade
  systemctl enable ssh.service
  killall sshd
  mkdir /run/sshd
  systemctl start ssh.service

  ProblemType: Bug
  DistroRelease: Ubuntu 21.10
  Package: openssh-server 1:8.4p1-6ubuntu2.1
  ProcVersionSignature: Ubuntu 5.13.0-23.23-generic 5.13.19
  Uname: Linux 5.13.0-23-generic x86_64
  NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
  ApportVersion: 2.20.11-0ubuntu71
  Architecture: amd64
  CasperMD5CheckResult: pass
  CurrentDesktop: XFCE
  Date: Tue Jan 11 19:11:47 2022
  InstallationDate: Installed on 2021-08-18 (146 days ago)
  InstallationMedia: Xubuntu 21.04 "Hirsute Hippo" - Release amd64 (20210420)
  SSHDConfig: Error: command ['pkexec', '/usr/sbin/sshd', '-T'] failed with exit code 255: Missing privilege separation directory: /run/sshd
  SourcePackage: openssh
  UpgradeStatus: No upgrade log present (probably fresh install)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1957104/+subscriptions