The new 1.2.1-S2 version provides an incorrect hostname in output sent to a syslog server. A couple lines in the /etc/hosts file are different between 1.2.1 and 1.2.1-S2:
127.0.0.1 localhost debian 127.0.1.1 vr16-1 # VyOS entry
### Autogenerated by host_name.py ### 127.0.0.1 localhost vr24-1
This produces different results when trying to find the FQDN:
bmtauer@vr16-1:~$ hostname -f vr16-1
bmtauer@vr24-1:~$ hostname -f localhost
The end results is that syslog data for ALL our vyos instances are getting lumped together as "localhost" rather than under specific instance names. This isn't the end of the world, but it does present difficulty.