redis-server fails at startup, installation failed

[Samuele Giovanni Tonon]

Hello,
it is quite easy to reproduce the bug:

root@fuffa:~# apt-get update && apt-get install redis-server
[....]

The following NEW packages will be installed:
  redis-server
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/397 kB of archives.
After this operation, 1.055 kB of additional disk space will be used.
Selecting previously unselected package redis-server.
(Reading database ... 421904 files and directories currently installed.)
Preparing to unpack .../redis-server_2%3a3.2.1-1_amd64.deb ...
Unpacking redis-server (2:3.2.1-1) ...
Processing triggers for ureadahead (0.100.0-19) ...
Processing triggers for systemd (231-9ubuntu2) ...
Processing triggers for man-db (2.7.5-1) ...
Setting up redis-server (2:3.2.1-1) ...
Created symlink /etc/systemd/system/redis.service → /lib/systemd/system/redis-server.service.
Created symlink /etc/systemd/system/multi-user.target.wants/redis-server.service → /lib/systemd/system/redis-server.service.
Job for redis-server.service failed because the control process exited with error code.
See "systemctl status redis-server.service" and "journalctl -xe" for details.
invoke-rc.d: initscript redis-server, action "start" failed.
● redis-server.service - Advanced key-value store
   Loaded: loaded (/lib/systemd/system/redis-server.service; enabled; vendor preset: enabled)
   Active: activating (auto-restart) (Result: exit-code) since sab 2017-02-11 18:58:26 CET; 14ms ago
     Docs: http://redis.io/documentation,
           man:redis-server(1)
  Process: 26199 ExecStart=/usr/bin/redis-server /etc/redis/redis.conf (code=exited, status=226/NAMESPACE)
  Process: 26196 ExecStartPre=/bin/run-parts --verbose /etc/redis/redis-server.pre-up.d (code=exited, status=226/NAMESPACE)

feb 11 18:58:26 fuffa systemd[1]: redis-server.service: Control process exited, code=exited status=226
feb 11 18:58:26 fuffa systemd[1]: Failed to start Advanced key-value store.
feb 11 18:58:26 fuffa systemd[1]: redis-server.service: Unit entered failed state.
feb 11 18:58:26 fuffa systemd[1]: redis-server.service: Failed with result 'exit-code'.
dpkg: error processing package redis-server (--configure):
 subprocess installed post-installation script returned error exit status 1
Processing triggers for systemd (231-9ubuntu2) ...
Processing triggers for ureadahead (0.100.0-19) ...
Errors were encountered while processing:
 redis-server
E: Sub-process /usr/bin/dpkg returned an error code (1)

Of course it is quite impossible to understand what is happening

root@fuffa:~# journalctl -xe
-- Subject: Process /bin/run-parts could not be executed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- The process /bin/run-parts could not be executed and failed.
--
-- The error number returned by this process is 2.
feb 11 19:01:09 fuffa systemd[31304]: redis-server.service: Failed at step NAMESPACE spawning /usr/bin/redis-server: No such file or directory
-- Subject: Process /usr/bin/redis-server could not be executed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- The process /usr/bin/redis-server could not be executed and failed.
--
-- The error number returned by this process is 2.
feb 11 19:01:09 fuffa systemd[1]: redis-server.service: Control process exited, code=exited status=226
feb 11 19:01:09 fuffa systemd[1]: Failed to start Advanced key-value store.
-- Subject: Unit redis-server.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit redis-server.service has failed.
--
-- The result is failed.
feb 11 19:01:09 fuffa systemd[1]: redis-server.service: Unit entered failed state.
feb 11 19:01:09 fuffa systemd[1]: redis-server.service: Failed with result 'exit-code'.
feb 11 19:01:09 fuffa systemd[1]: redis-server.service: Service hold-off time over, scheduling restart.
feb 11 19:01:09 fuffa systemd[1]: Stopped Advanced key-value store.
-- Subject: Unit redis-server.service has finished shutting down
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit redis-server.service has finished shutting down.
feb 11 19:01:09 fuffa systemd[1]: redis-server.service: Start request repeated too quickly.
feb 11 19:01:09 fuffa systemd[1]: Failed to start Advanced key-value store.
-- Subject: Unit redis-server.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit redis-server.service has failed.
--
-- The result is failed.
feb 11 19:01:09 fuffa systemd[1]: redis-server.service: Unit entered failed state.
feb 11 19:01:09 fuffa systemd[1]: redis-server.service: Failed with result 'start-limit-hit'.

Of course, launching it from command line simply works:

root@fuffa:~# su - redis -s /bin/bash
redis@fuffa:~$ /usr/bin/redis-server /etc/redis/redis.conf
redis@fuffa:~$ echo $?
0
redis@fuffa:~$ ps auxw| grep redis-ser
redis 31431 0.0 0.0 40288 5836 ? Ssl 19:04 0:00 /usr/bin/redis-server 127.0.0.1:6379

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Alexander Zharinov (zharinov)]

I can reproduce this bug inside LXC container with Ubuntu 16.04. It is related to bug of systemd: "https://github.com/systemd/systemd/issues/6121". There is a workaround to disable PrivateDevices for redis-server service. Example:

    $ sudo su
    $ mkdir /etc/systemd/system/redis-server.service.d/
    $ cd /etc/systemd/system/redis-server.service.d/
    $ echo '[Service]' > redis.override.conf
    $ echo 'PrivateDevices=no' >> redis.override.conf

My software versions: redis-server 2:3.0.6-1, systemd 229-4ubuntu17.