Need guidance and exact instructions on how to perform a file system check on a Dell RHEL 6.x NSS-HA NFS (XFS file system).

Dell engineers installed two Dell PE R620's with two PV3260 SAS drive array enclosures almost 1.5 years ago. The two engineers no longer work for Dell and they left us with no documentation or best practices (when to do file system checks, etc.). All we got for docs was a single sheet of paper with a few command line commands. We are running RHEL v6.x NSS-HA NFS (xfs file system). It has been running great for us but we have never done a file system check on it and do not know how to do it and the best procedure in doing it. Total data equals about 40 TB and it is used by our university department staff, faculty and students. Can anyone point me to some extensive docs on RHEL NSS HA NFS and how to properly do the file system check? We have a short window this weekend starting Sunday morning thru Monday to perform this disk check. Any help would be greatly appreciated.

Thanks,

Greg Corlett