Issue : While adding new account in the Credential management of application type UNIX , "Failed to establish communication with remote host " error is displayed by Credential Manager.
Problem : "utmp, wtmp, btmp and variants such as utmpx, wtmpx and btmpx" are files on Unix-like systems that keep track of all logins and logouts to the system. Over the period of time this files size grows, When CA PAM tries to login to verify the credential with the UNIX server it is unable to process till the end of the file with in stipulated time out duration.
Solution : Either increase the timeout value of the "Update/Verify credential script" in UNIX application(Doing so didn't work for me)
Tested solution : Clear the entries on the "utmp, wtmp, btmp and variants such as utmpx, wtmpx and btmpx" files on the Unix server.
Step 1 : Login to Unix server via root or equivalent account.
Step 2 : Initialize the above mention files based on your operating system flavor by using the command "> var/adm/wtmps"
Step 3 : If you have multiple file as mention above then you need to do it for other file also.
Step 4 : Login to CA PAM , Navigate to Password management and try adding that account again account.It should work this time.