This article applies to AppGate (classic).
Changing hostnames in an existing cluster may end with a cluster not fully functioning after the reboot (reboot needs to be done after hostname changed).
This issue is tied ito ag_mgmtd failing to start even after a reboot. This applies to version >= 10.
To come around this issue, log into a terminal on the node(s) of the failing ag_mgmtd as root, then restart the ag_mgmtd.
appgate:~# /etc/init.d/ag_mgmtd restart
Stopping AppGate management daemon
Starting AppGate management daemon