Datastage authentication connection error

[abhik05]

We had one datastage server version 8.7 installed on a linux system(hostname vhost1307).We used to connect to this server using users created in web console.

Now for performance enhancement we have got another datastage server v8.7 installed on a different linux ssytem (hostname vhost4507).All the users and passwords are same.This new server instance is created with the image of previous server. So, whatever we had is completely copied to this new server.

But while connecting though client we faced below mentioned issue:
Failed to authenticate the current user against the selected Services Tier

The URL [iiop://vhost1307.site1.compute.ihost.com:2825] that is used to connect to the host [170.224.161.202] on the port [9080] is incorrect or is not trusted. To trust the connection, import the signer certificate into the local truststore, by running the following UpdateSignerCerts command

Even in the web console also after logging with new datastage server ipaddress ,in the engine (Admin->domain management->engine credential)the old hostname(vhost1307) is being shown only instead showing the new hostname(vhost4507) .

Please suggest.
Thanks
Abhik