WHM/cPanel – List of all ports and a script to test them
Here is a Bash script to test all inbound cPanel ports: 20 FTP 21 FTP 22 SSH 25 SMTP 26 SMTP 53 DNS 80 HTTP
whm
How to use strace to trace network requests from an internal process on your network
Here is how you can see what ports/packets a local process is doing: strace -e trace=network -f whmapi1 validate_current_dkims domain=example.com 2>&1 | grep -E “(connect|bind|socket)”
PHP-FPM aborts/failures on WHM/cPanel with Apache – randomly stops working – intermittently
Symtoms This problem only happens on busy servers. It may or may not be preceded by these events: root@server:~# cat /opt/cpanel/ea-php82/root/var/log/php-fpm/php-fpm/error.log | grep -i rais
MySQL error – Could not increase number of max_open_files to more than 10000 (request: 40000)
Looking at a MySQL error log showed some interesting new errors. Here is the log file: 2025-02-23T06:43:15.664775Z 0 [Warning] [MY-010140] [Server] Could not increase number
cPanel & WHM update failure in upcp script – The following events were logged: “scripts/update-packages”.
Background If you have many cPanel servers you’ll find from time to time they don’t update. This is unfortunately a more common problem than usual.
How to install an older version of WHM
Scenario You’re doing disaster recovery and you need to install an older version of WHM. The reason is you have legacy PHP 7.4 websites, that
JetBackup 5 on WHM doesn’t back up suspended accounts and give lots of partial completions
On JetBackup 5 and WHM you have a big problem that suspended accounts are not backed up. Loads of errors every day in the log
How to deal with WHM/cPanel Mail Hold Email holding in /etc directory
WHM brings up this message: This message was created automatically by mail delivery software. A message that you sent could not be delivered to one
WHM/cPanel’s WP Toolkit fails on many functions with out of memory
You have to use WHM. The default for PHP 8.1 for example is 32MB, move it to 64 MB and things will improve. WHM /
Connection from [a.b.c.d]… refused: too many connections and Exim
At times your Exim server might be overwhelmed: 2023-11-09 12:04:05 Connection from [188.234.244.30]:3802 refused: too many connections Your server is most likely under attack. Check