Mid server is not showing as started on Instance but the service status is starting on the mid server host.
The below error can be seen in agent logs after starting the mid server.
07/02/20 13:56:26 (096) StartupSequencer SEVERE *** ERROR *** SOAP Response: Status code=0, Response body=null
07/02/20 13:56:26 (096) StartupSequencer SEVERE *** ERROR *** Problem invoking InstanceInfo on https://instance.service-now.com: Please check that the InstanceInfo page exists in the sys_public table and active="true".
07/02/20 13:56:26 (096) StartupSequencer SEVERE *** ERROR *** java.lang.IllegalStateException: Authentication state already initialized
(Network Configuration issue) Please check that the MID server can ping the instance: https://instance.service-now.com
You may also need to configure the network that the MID server uses to allow traffic over TCP port 443.
07/02/20 13:56:26 (096) StartupSequencer SEVERE *** ERROR *** test failure
The mid server is able to telnet to the instance and port 443 is opened on the mid server host.
One of the reason for this issue can be port 443 is not opened on the mid server host for instance.
But, the issue in this case is with the invalid proxy credentials. The proxy username and password used for mid server were expired or not valid any more in the client network.
In order to resolve the issue.
1) Stop the mid server service from host machine
2) Change the proxy username and password from the existing ones to the working userid and password.
3) After changing these details in the config file, start the mid server.
4) The mid server will show up and running on instance now.