CentOS

The question about mdadm is only applicable if /boot (or / if /boot is part of that) is on an mdadm device. It has been know that an mdadm aray can lose one of its members so the drive that has dropped out no longer gets updated. If the non-updated drive is the one that the BIOS is set to boot from ...

Also, I believe the kernel install updates /etc/grub2.cfg or /etc/grub2-efi.cfg which should be symlinks to their /boot/grub2 equivalents. IF the symlink is broken and the /etc files are real files then it'll update the real files in /etc but not the ones in /boot... which are the ones that grub rea...

Have you got mdadm RAID?

You'll need to _add_ logging to it so that it tells you what it is doing.

Also check in /var/log/messages for errors.

Change your scripts so they log what they do and any errors they get. Without that, any answers will just be guesswork.

Report it to Nagios XL. They are using something which has been dead for at least 5 years and will never come back. They need to change to use something else.

A quick google says "use PDO". It seems php-mssql was removed from php 7.x.I see php-pdo is in appstream in EL9 but it also looks like you need php-pdo-dblib from EPEL to allow MSSQL use.

Why have you installed CentOS 7 now? It dies in June this year.

Sorry to tell you but there is no CentOS 8. Red Hat abolished CentOS at the end of 2021 and CetnOS 8 is already dead. CentOS 7 limps on to its EOL in June this year and then there will be no supported CentOS versions. There are two replacement distros that sprang up to take teh place that CentOS lef...

I'll "suggest". Do not deploy CentOS 7 now. It reaches end of life in 4 months time and then it will be dead. It's not worth the effort to install it now, use something newer.