SSL site-to-site 9.401-11 with 9.355001 no routing

Question

Hi all, 
 we have several Sophos UTM devices connected via SSL together but the main unit has upgraded to the latest 9.401-11 and now the clients are not reachable anymore. The clients are still at 9.355001. I do read that the new 9.401-11 had some fixes for SSL-VPN routing but we never experienced any problems till this update. 
 We can still see that the clients makes the connection and it also becomes green but, the routing is not working anymore. Also a tracert via the tools menu does not give any response. It is not possible to update the devices manually because they are at remote locations behind other firewalls so, they need the link to work to get the update.

Steefph · Accepted Answer

The clients are UTM devices that connect via SSL VPN to the "master" UTM. This was working fine till the update. I've found out that I have to add the IP that the "Client" gets from the "master" to the Firewall rules in 2-way direction. This was not needed before the update. 
 Perhaps it was working before due to an error that was part of the fixes done in the patch. Anyway, it is working again. 
 
 Sorry for the late reply, we had a long weekend here with great weather ;)