On Wed, Nov 4, 2009 at 7:17 PM, Nils Goroll <slink at schokola.de> wrote:
> Hi Binu and Hartmut,
>
> (Binu, sorry for the typo of your name in my last mail)
>
>>> * For non-PxFS ("HA-local") mounts, fssnap should work technically, even
>>> though it is not supported. Care should be taken to minimize the impact
>>> of
>>> the necessary I/O pauses during the snapshot process, for instance by
>>> temporarily disabling cluster monitoring of resources depended upon the
>>> filesystem to be snapshotted.
>>
>> Even for non-HA mounts, the project complexity will be the same.
>
> I hope I understand the difference between HA and non-HA PxFS, but I was
> referring to non-PxFS mounts on either node of the cluster, which I know by
> the name "ha-local".Ooops, my bad, didn't read your reply properly. > My understanding is that, in this case, no PxFS is involved - correct? Your understanding is correct. For HASP controlled file systems there is no PxFS and it should be possible to use fssnap with judicious control of who is accessing the file system. cheers Binu > Thank you anyway for your additional explanations regarding the two PxFS > cases. > > Hartmut, > >> Sure, UFS snapshots are temporary (see fssnap_ufs(1M)), but IIUC, >>> snapshotting an ha-local FS in a cluster should not be any different >>> from snapshotting any other (non-root) FS in that the (clustered or >>> non clustered) node may die at any time, so the snapshot will get >>> lost, right? > >> Correct! But there was a discussion along the lines that this is >> unacceptable in an HA environment. > > I think it probably will be for many HA-Applications, but some might live > happily with that limitation, so, as most often, the best answer is probably > "it depends". ;-) > > Nils >
