RHEL mount hangs: nfs: server […] not responding, still trying

Environment

• Red Hat Enterprise Linux 7
• Red Hat Enterprise Linux 6
• Red Hat Enterprise Linux 5
• NFS Client (nfs-utils package)
  

  Issue

  • NFS shares hang with the following error(s) in /var/log/messages:

    kernel: nfs: server <NFSservername> not responding, still trying

    kernel: nfs: server <servername> not responding, timed out

  • Resolution

  • The fix on our system was to lazy unmount, stop any processes that might be using the mount point, and remount.umount -l (mountpoint)
    service yum-updatesd stop
    mount (flags) (mountpoint)