We have an agent on a server in a restricted cloud network. In order for the agent to communicate with the manager we need to set the the agentparm.txt to use the FQDN of the manager server.
communication.manageradress_1=managerhostname.fqdn.com
When the manager server reboots the agentparm.txt is recreated and the non FQDN address is used
communication.manageradress_1=managerhostname
Release : 12.0
Component : Workload Automation ESP dSeries
In Topology -> Server instance parameters -> 'IP address/name where all server sockets should bind to", this setting is likely configure to use the non-fqdn manager hostname. This setting, in combination with the "Remember Manager address changes between restarts" property setting (at agents properties) will cause the agentparam.txt file on agents to get updated with the manager id used by the server instance parameter -> 'IP address/name....' property when the management server is restarted.
Update the Server instance parameters -> 'IP address/name where all server sockets should bind to" property to use a name that is resolvable by all agent machines. When changing this value, the dSeries server service should be stopped/started for the setting to take effect.