RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

The NFS(5) manpage states:

 local_lock=mechanism
       Specifies  whether to use local locking for any or both of the flock and
       the POSIX locking mechanisms.  mechanism  can  be  one  of  all,  flock,
       posix, or none.  This option is supported in kernels 2.6.37 and later.


It appears that this mechansim has been back-ported into the 2.6.32 kernel
in e.g. linux-2.6.32-220.el6/fs/nfs/super.c

So local_lock does in fact work in, I believe, all RHEL6 releases

nfs(5) man page is part of the nfs-utils package

[root@dhcp12-241 nfs-utils-1.2.3]# man ./utils/mount/nfs.man | grep local_lock=mechanism -A 10
       local_lock=mechanism
                      Specifies  whether to use local locking for any or both of the flock and the POSIX locking mechanisms.  mechanism can be one of all, flock,
                      posix, or none.

                      The Linux NFS client provides a way to make locks local. This means, the applications can lock files, but such locks provide exclusion only
                      against other applications running on the same client. Remote applications are not affected by these locks.

                      If this option is not specified, or if none is specified, the client assumes that the locks are not local.

                      If all is specified, the client assumes that both flock and POSIX locks are local.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2014-1407.html