Firewall is not sending logs to syslog with Syslog-ng log showing "Error resolving hostname"

• Syslog is not receiving logs from firewall
• Syslog-ng log showing "Error resolving hostname":

Nov 27 06:27:07 FWPA1 syslog-ng[24640]: Error resolving hostname; host='splunk-syslog-ghcc.splunk.example.com'
Nov 27 06:27:07 FWPA1 syslog-ng[24640]: Initiating connection failed, reconnecting; time_reopen='5'

• dnsproxy.log showing "Failed to resolve domain name" for syslog hostname:

2023-11-29 10:48:19.383 +0000 Warning:  pan_dnsproxy_log_resolve_fail(pan_dnsproxy_util.c:651): Failed to resolve domain name:splunk-syslog-ghcc.splunk.example.com AAAA after trying all attempts to name server(s): 10.250.0.1  10.250.0.2

• Ping to hostname works fine:

user@FWPA1> ping host splunk-syslog-ghcc.splunk.example.com
PING splunk-syslog-ghcc.splunk.glblint.example.com (10.240.72.88) 56(84) bytes of data.
64 bytes from splunk-syslog-ghcc.splunk.glblint.example.com (10.240.72.88): icmp_seq=1 ttl=252 time=30.0 ms

• All platforms
• PANOS 9.1, 10.1.9 or before, 10.2.4 or before  

• Caused by the software issue PAN-208210 where syslog config changes to the IP address or port number were not applied without restarting the management server.

1. Upgrade to 10.1.10 or later, 10.2.5 or later, 11.0.1 or later