Hi Tejas,
I guess you are using whm/cpanel on your server and this is related to hostname lookup. There are few things you can try
Code:
1. make an A entry in your DNS server for that server server1.domain.com with that mapping IP
2. Check your hostname and make it same as that server1.domain.com
3. edit /etc/hosts file and put that server1.domain.com with it's IP
I hope this will fix the issue.
Thank you
Manish