Since our servers upgraded to Alma Linux 8.9, each time the servers reboot, CSF does not operate as normal until after its restarted via WHM.
On one server that uses PHPMailer and Office 365 SMTP, any emails that are sent by the cPanel account will fail due to "network is unreachable" and in the /var/log/messages it shows outgoing connection attempts to port 587 being blocked. This is happening whether SMTP_BLOCK is on or off, but can be resolved by simply restarting CSF.
On another server, this one is a remote server that has my external IP address whitelisted for WHM access so no other IP address can access WHM. However, after a server reboot, I cannot remotely access WHM (connection timed out). Thankfully I still have remote access to the VM and by simply restarting CSF, I can access WHM remotely.
Are you aware of such issues with CSF?