I am using CA API Gateway AMI appliance.The Gateway is connected to AWS mysql community edition.so the database is external.As it is AMI, upto now I haven't touched any network settings because all then/w config points to DHCP.Today as i want to change gateway timezone from ssconfig main menu.I have configured some hostname and ntp.after that I am unable access gateway from policy manager or putty.My question is can aws people locate the gateway.And if there is any issue with the ami I don't have any backup of the machine.But as database is external the database doesn't have any issue.As of my knowledge the gateway seetings will be stored in database.Can you please let me know if we cannot bringup ami.If we spin up ami and connect it to existing database will the previous services and all the configuration will be available in new gateway.
This issue will be best solved with a support case by going to https://support.ca.com.
That being said, it looks like this may be an issue with hostname changes you had made to the system. There are a litany of questions we need to ask, but my initial thoughts are around the hostname changes you made. Did the hostname change you made also have an entry in your DNS? Can you reach the system from its IP?
if you want the new gateway node connect to the an existing database, you might try creating the new gateway node using the same cluster passphrase of the old gateway.