We have multiple sites and have started to purchased WAP 150's instead of the 321's. We have used 321's for a long time and were great. The 150's are very similar and so we have now been setting those up. On two sites our 150's have been losing the gateway and cannot route beyond the local LAN.If I look at the gateway in the config it is there but I cannot ping the WAP's over the WAN. I can over the LAN. This causes us an issue as they use RADIUS for authentication and have to go over the WAN for this. Never been an issue with any other WAP we have ever had. The same fault has now occurred on two separate WAN sites so I am thinking a bug.
If I login over the LAN to the GUI and overtype the last octet of the gateway address and choose save immediately the WAP is pingable over the WAN and can now authenticate again.
I have this issue on a few WAP150's. From within the same subnet you can navigate to the login page, go to LAN IPv4 settings and just click save (no need to alter any settings), and the gateway works right away.
There is a firmware update (184.108.40.206) which fixed it for me, but it created other issues (now the AP forgets the key for RADIUS servers that are defined in the network settings, not global settings).