Re: md multipathing failover

[Greg Swift <greg netops gvtc com>]

Gunther Schlegel wrote:

> Hi,
>
> I am becoming a little desperate with my SAN (EMC Clariion, Qlogic HBAs)
> connections.
>
> With RHEL3 I just use the internal failover of the Qlogic driver. This
> works fine. 
>
>  
i've the same configuration...

> However, the Qlogic-modules in FC2, FC3 and RHEL4 lack this feature. I
> therefore rebuild the kernel with the Qlogic-driver on some FC2/3 hosts
> to have the same functionality as in RHEL3.
>
> ..[snip]..
>  
>
> Besides, the multipath device is not assembled in a correct way during
> bootup on FC2 as it uses raidtools instead of mdadm, but I corrected
> this at runtime, so this cannot be the reason.
>
> Question: - Does multipathing actually work with RHEL4? Did anyone pull
> the plug to test it? Does it work on RHEL3? Does it even work on FC2 and
> I am just missing something?
>  
please let me know what you figure out, I was actually getting ready to 
re-deploy my secondary server as rhel4 and see how well it stood up, 
ecspecially since I wasn't 100% happy with the "harmless" errors that I 
was seeing in rhel3 (it has to do with the multipath and multiple 
servers, the system allocates devices, but since they don't really 
exist, it errors).  I'll let you know how my side goes once I get around 
to it...

-Greg