Solarwinds log forwarder clients stop forwarding logs when syslog server reboots

Hello,

When we reboot our syslog server for maintenance purposes, all the clients stop forwarding logs 
and we must restart the Solarwinds log forwarder Windows service on each of them to solve the issue.

There is nothing relevant in the event viewer or in the program log files.
We are also using TCP port 514 for forwarding. Is there anywhere I can look to troubleshoot ?

Thanks in advance.