Another option I tried was service iptables stop just to see if there was a firewall rule causing an issue. But yum update still fails: yum update Loaded plugins: fastestmirror, presto Setting up Update Process Loading mirror speeds from cached hostfile Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os&infra=stock error was 12: Timeout on http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os&infra=stock: (28, 'connect() timed out!') Error: Cannot find a valid baseurl for repo: base