[ClusterLabs] [Linux-HA] Antw: Re: Antw: Re: file system resource becomes inaccesible when any of the node goes down

[Lars Marowsky-Bree]

On 2015-07-07T12:23:44, Ulrich Windl <Ulrich.Windl at rz.uni-regensburg.de> wrote:

> The advantage depends on the alternatives: If two nodes both want to access the same filesystem, you can use OCFS2, NFS, or CIFS (list not complete). If only one node can access a filesystem, you could try any journaled filesystem (a fsck is needed after a node crash).

A journaled file system does not require a fsck after a crash.

> If you use NFS or CIFS, you shift the problem to another machine.
> 
> If you use a local filesystem, you need recovery, mount, and start of your application on a standby node.
> 
> With OCFS2 you'll have to wait for a few seconds before your application can continue.

The recovery happens in the background with OCFS2 as well; the fs
replays the failed node's journal in the background. The actual time
saved by avoiding the "mount" is negligible.



Regards,
    Lars

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Architect Storage/HA
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