There is a slight performance related reason for exporting disk partitions individually, the performance boost is server-side as Paul says. The advantage is that the no_subtree_check can be used without any additional security risk. It is probably the case that the /export/base/a is a partition, is exported with no_subtree_check, and therefore there is a small performance boost. Preventing server side mount point traversal can also form part of a security mechanism if servers have different security options for different mount points, but in this case mounting server:/export/base wouldn't give you the same client view of the filesystem tree as mounting each individually if it worked at all. Cheers, Sean On 27 July 2016 at 23:21, Paul Heinlein <heinlein at madboa.com> wrote: > On Wed, 27 Jul 2016, Frank Thommen wrote: > > Hello, >> >> does it in any respect (throughput/performance, cpu load, I/O load, >> resilience, ...) matter, if one mounts subdirectories of an NFS (v3) export >> into separate directories or if one just mounts the parent directory? >> >> I.e. like this: >> >> server: /export/base/a -> /mnt/a >> server: /export/base/b -> /mnt/b >> server: /export/base/c -> /mnt/c >> server: /export/base/d -> /mnt/d >> server: /export/base/e -> /mnt/e >> >> or simply like this: >> >> server:/export/base -> /mnt >> > > Performance wise, any bottleneck will almost certainly be tied to the > disks on the back end, not the nfs process itself. > > There are a couple good reasons for splitting up the mounts: > > 1. They can have different export restrictions (e.g., for different > client hosts, ro vs. rw permissions, user squashing). > > 2. /base/[a-e] live on different RAID arrays and might benefit from > different management cycles; that'd also be a case where multiple > exports might be a good idea. That said, I've never managed an > exported filesystem consisting of different arrays; we've always > exported at the RAID level or below. > > -- > Paul Heinlein <> heinlein at madboa.com <> http://www.madboa.com/ > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos >