I am getting error when using ping google.com saying could not resolve host address. I am using internet under a proxy server and i am getting my ip through dhcp dynamically and dns is set static. I could see in wireshark that tcp handshake syn between my computer and the dns server is sent but ack is received with reset flag set. Contents of /etc/resolv.conf:nameserver 208.67.222.222
Unable to resolve host name ping google.com ubuntu
ubuntu;networking;dns;ping
Since you're getting your IP via DHCP, have you tried using the DNS server that may have been provided via DHCP?  You probably need to point to an internal DNS server.  Suggest you talk to your networking team.