Can't get clients to stay online

My setup is in AWS with a PFsense firewall that is NAT to the internet.
Systems are on the same subnet and should just be talking to each other.

Installed server and seems to be running fine.
Installed client on two servers. They show up on the urbackup server then about a minute latter offline they show offline. There is no information in the logs to say why this is happening. Clients and ports are all good. Not sure where to go from here.