Re: Qlogic FC Multipath and engenio

[Duncan Robertson <duncan@zog.net.au>]

On Tue, 2006-01-31 at 19:57 +0100, Andrew Miehs wrote:

> I have a multipath setup between my 2 port hba on each of my servers,  
> and my two
> raid systems have 2 ports as well, all connected over 2 qlogic  
> switches (not connected
> to each other). The raid systems are StorageTek boxes with then  
> engenio software - 9.15
> 
> This means, that each server see each disk twice.
> 
> I have just compiled a 2.6.15.2 kernel for this setup.
> 
> What do I need to do to run multipath? Does the qlogic (qla2xxx)  
> driver in the

One way to do it is use mdadm - it has a multipath mode where you can
make an /dev/mdX device that is aware that it is just seeing the same
device via different paths. This works quite well and can be managed via
the usual mdadm commands.
  This doc has further info:
     http://www.sun.com/storage/san/linux_multipathing.pdf


There is also a way to configure it inside the qlogic driver using
Qlogics SANsurfer java config app where it is more transparent to the
rest of the OS, we have got that working but I can't remember the exact
configuration option.

bye,

Duncan