Re: [linux-lvm] LVM + Multipathing

[Luca Berra <bluca comedia it>]

On Sat, Feb 17, 2007 at 09:52:27PM +0530, Ritesh Raj Sarraf wrote:
> Hi,
>
> I have a question regarding the combination of LVM + Multipathing in a SAN
> environment.
>
> I have a LUN mapped to a host using iSCSI. I have two two paths to the LUN. This
> setup, using multipathing, provides me failover functionality.
>
> My question is how does LVM react to path failures ?
> In a failover environment, multipathing can take upto 120 seconds to detect that
> the active path to the LUN is no more available and then switch to the
> secondary path. During this 120 seconds, how does LVM react ? Does it really
> sense that the device is offlined ? Or that information is never passed to LVM
> and it just allows I/O to happen leaving that responsibility to the
> multipathing layer ?

i believe LVM does not react at all.

L.

--
Luca Berra -- bluca comedia it
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