/etc/resolv.conf got override by NetworkManager during bootup
/etc/resolv.conf got override by NetworManager :
we updated the file /etc/resolv.conf
with ansible playbook in user_data but NetworkManager is started at very end of the instance booting process, so all the changes are gone after it. That's why we are having issue with DNS lookup for login001.cm.cluster in http-proxy
Edited by Eesaan Atluri