Container Version does not save settings properly


Well-Known Member
Nov 23, 2011
I'm starting to look into moving from a KVM over to a LXC container for my filters.

I've set one up, but every time I go to make a change to some of the settings, seemingly the ones that require postfix modification, I am getting the following error:

update config section 'mail' failed: command 'systemctl restart postfix@-' failed: exit code 1 (500)

I get this when I look at the status of postfix:

systemctl status postfix.service
● postfix.service - Postfix Mail Transport Agent
Loaded: loaded (/lib/systemd/system/postfix.service; enabled; vendor preset: enabled)
Active: active (exited) since Sat 2019-04-06 08:32:58 EDT; 2h 26min ago
Process: 253 ExecStart=/bin/true (code=exited, status=0/SUCCESS)
Main PID: 253 (code=exited, status=0/SUCCESS)
Tasks: 0 (limit: 629145)
CGroup: /system.slice/postfix.service

Apr 06 08:32:58 swarmx1 systemd[1]: postfix.service: Failed to reset devices.list: Operation not permitted
Apr 06 08:32:58 swarmx1 systemd[1]: Starting Postfix Mail Transport Agent...
Apr 06 08:32:58 swarmx1 systemd[1]: Started Postfix Mail Transport Agent.
Apr 06 08:32:58 swarmx1 systemd[1]: postfix.service: Failed to reset devices.list: Operation not permitted

On my PVE hosts, I am running the following version:
pve-manager/5.3-11/d4907f84 (running kernel: 4.15.18-9-pve)

Anyone run into this and if so, what have you done to get around it? I've tried a few different configs of the LXC containers and they all exhibit the same error.

To test, do the following:

In your Admin section, go to Configuration --> Mail Proxy --> TLS and try enabling TLS. It will give you the above error and once you close out the actual change, the change is there in the GUI at least. It happens every time I make a change to something.

However, it doesn't exhibit the issue on Configuration --> Mail Proxy --> Transports.
That seems to save fine.

Any thoughts?

postfix.service: Failed to reset devices.list: Operation not permitted
This can be ignored safely. The reason postfix is failing is probably something else.

What kind of Container are you using? Can you post the config? (`pct config CTID`)

On another note, if you're not already using it, we recently created a new Container for PMG, you should be able to find it among the other templates. (proxmox-mailgateway-5.2-standard_5.2-1_amd64.tar.gz)
Thanks for this and sorry about the late reply. I did use the mail gateway template and thats what caused me the issues. I removed it and then recreated it as an "unprivileged container" and that seems to have done the trick with it and not they are working.


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