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 126.96.36.199, the second DNS server is 188.8.131.52, and the third DNS server is 184.108.40.206. If your company domain name is mydomain.com, then the /etc/resolv.conf file would contain the following lines.
nameserver 220.127.116.11 nameserver name 18.104.22.168 nameserver name 22.214.171.124 domain mydomain.com search mydomain.com