Edit /etc/resolv.conf and ensure that the entries are similar to the following:
nameserver server 1 IP address nameserver name server 2 IP address nameserver name server 3 IP address domain your-domain-name search your-domain-name
For example, assume the IP address of the first DNS server is 22.214.171.124, the second DNS server is 126.96.36.199, and the third DNS server is 188.8.131.52. If your company domain name is mydomain.com, then the /etc/resolv.conf file would contain the following lines.
nameserver 184.108.40.206 nameserver name 220.127.116.11 nameserver name 18.104.22.168 domain mydomain.com search mydomain.com