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