Failed cluster and "proxy timeout"

Question

We had 2 physical SEA appliances working in cluster. The master has failed, so the secondary inherited its IP address. 
 I can log into that appliance GUI but each time I try to access "configuration" menu it is giving me "proxy timeout" error. Other menu items seem to work, but very slow. I suspect the secondary wants to connect to the master, which is no longer available. Is there a way I can remove cluster configuration or access configuration without GUI?

emmosophos · Answer

Hello Marcin, 
 Thank you for contacting the Sophos Community. 
 I have moved this thread to the correct group. 
 Only Sophos Support can access the appliance backend, so I would recommend you to reach out so they can assist you with this. 
 However, if you have access to the GUI of the Secondary appliance, and you go to System > Clustering, see if you can remove it from there. 
 Regards,