Mounting NFS export vs SAN mounted as NFSv4

<!-- SC_OFF --><div class="md"><p>I&#39;ve tried searching around for an answer on this, and not sure if I&#39;m asking the question wrong or if I just suck at googling.</p> <p>We have a requirement at work to mount shared storage as NFSv4 for a picky HA application. It was decided that we could use shared SAN storage, and mount it as NFSv4 and this would fit our needs. Fast forward, and now a Senior on my team, has retracted the decision saying that mounting the SAN as NFSv4 is actually using GFS2, and doesn&#39;t fulfil the NFSv4 requirements from the application perspective. </p> <p>Can someone explain why this is? My Senior just kept saying, &quot;Mounting is as NFSv4 still uses the GFS2 file system, and it&#39;s not NFSv4.&quot; </p> <p>If someone could explain this to me, I would greatly appreciate it. I just can&#39;t wrap my head around it. Regardless of the type of storage, or file system, when it gets mounted as a NFSv4, that handles the locking mechanism, and makes the type file system it sits on, irrelevant.</p> </div><!-- SC_ON --> submitted by