We have a recurring problem with our server where all ip addresses become “improperly configured” after a random interval of time.
It can work for weeks without any problem and suddenly break apart (most of time in the middle of the night…).
The server is running on Debian 9.12 with Plesk 18.
When the error occurs all websites become unavailable. If we look at the Plesk interface, we can see all ip addresses (except the original one that came with the server) on error with the following message :
“This IP address is not configured properly”.
Plesk offers a “Repair” link for each ip which solves the problem.
Restarting the server also fixes the issue.
I didn’t find anything in the system’s logs, but I’ve found these errors in the Plesk’s logs:
stderr: nginx: [emerg] bind() to XX.XXX.XXX.XXX:443 failed (99: Cannot assign requested address) nginx: configuration file /etc/nginx/nginx.conf test failed [2020-09-10 05:52:55.520] ERR [util_exec] proc_close() failed ['/opt/psa/admin/bin/nginx-config' '-t'] with exit code  [2020-09-10 05:52:55.520] ERR [panel] '/opt/psa/admin/bin/nginx-config' '-t' failed with code 1.
There is one error of this kind for each IP address.
I don’t know if it may be related, but just before the first error in the log, there is this error:
[2020-09-10 05:50:07.606] ERR [panel] 2020-09-10 05:50:03 INFO: pum is called with arguments: ['--list', '--repo-info', '--json'] 2020-09-10 05:50:07 ERROR: W:GPG error: http://ppa.launchpad.net/ondrej/php/ubuntu focal InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 4F4EA0AAE5267A6C, E:The repository 'http://ppa.launchpad.net/ondrej/php/ubuntu focal InRelease' is not signed., W:Updating from such a repository can't be done securely, and is therefore disabled by default., W:See apt-secure(8) manpage for repository creation and user configuration details., W:GPG error: https://repo.cloudlinux.com/kernelcare-debian/6 stable InRelease: The following signatures were invalid: E58FE9B3FE3B0470525159BD6DC3D600CDEF74BB 2020-09-10 05:50:07 ERROR: Exited with returncode 1. [2020-09-10 05:52:53.165] ERR [util_exec] proc_close() failed ['/opt/psa/admin/bin/nginx-config' '-t'] with exit code  [2020-09-10 05:52:53.165] ERR [panel] '/opt/psa/admin/bin/nginx-config' '-t' failed with code 1.
It’s related to a custom repository that we added months ago. At first glance it doesn’t seem related but I don’t know, the error is only 2 minutes ahead of the first IP address related error.
Do you have any insight to share?
Thanks for your help.