rdate reports an error when upcp runs

Symptoms

When upcp runs, errors similar to the following appear in the cPanel update log (/var/cpanel/updatelogs/last).

[2022-08-24 07:54:22 -0300] E [/usr/local/cpanel/scripts/rdate] Failed to run due to the 10 second timeout being exceeded.
[2022-08-24 07:54:22 -0300] E [/usr/local/cpanel/scripts/rdate] The “/usr/local/cpanel/scripts/rdate” command (process 631315) reported error number 4 when it ended.

[2022-09-13 05:26:12 +0200] E [/usr/local/cpanel/scripts/rdate] Can't connect to rdate.cpanel.net:37 Connection refused
[2022-09-13 05:26:12 +0200] E [/usr/local/cpanel/scripts/rdate] The “/usr/local/cpanel/scripts/rdate” command (process 1430475) reported error number 111 when it ended. 

Description 

The rdate script adjusts the system clock on servers not running an NTP daemon. The errors occur when the server is unable to contact rdate.cpanel.net on TCP port 37. This can occur if the server is unable to resolve rdate.cpanel.net or if outbound TCP port 37 is blocked.

Workaround

If the server is unable to resolve rdate.cpanel.net, the resolvers will have to be changed or outbound UDP port 53 will have to be opened, depending on what caused the DNS resolution failure.

If the server is unable to communicate over port 37, outbound TCP port 37 will have to be opened in the firewall.

Additional Resources

What ports should I open in my network firewall?