On Thu, Oct 23, 2003 at 06:50:29PM -0600, adimaths@softhome.net wrote:
> Hi,
>
> I am facing a problem in using LVM bundled with Suse Enterprise server 8
> ,connected to storage area newtork
> System configuration:
> A storage area network is connected to a server with OS Suse Enterprise
> server 8.
> So there are multiple scsi devices whose physical disk is identical.
>
> We are creating a Pseudo device file asscociated with identical scsi devices
> using a driver that we have created.
> eg : /dev/pseudo-device -> /dev/sda , /dev/sdb
>
> Now using the bundled LVM on such pseudo device is a problem.
> problem details:
> pvcreate /dev/pseudo-device
> [result] ok.
>
> pvscan
> [result] it shows the scsi device associated with this pseudo device ie
> /dev/sda and not our pseudo device.
>
> If LVM bypasses our pseudo device then the purpose of creating this device
> and associating it with scsi is futile.
>
> The irony is, LVM works fine on RH 2.1 kernel = 2.4.9-e.3 and also with RH
> 7.2
> However the above mention problem is observed on Suse Enterprise server 8
> ,RH 2.1 kernel =2.4.9-e.25, RH 7.3 and RH 8.0.
>
> Would request you to clarify the following :
> 1>Could you please tell me how this problem can be rectified ?
Change the sort-order (as you suggested below)
>
> 2>Is it that Lvm that is bundled with the OS can't be used for
> the above mentioned purpose ?
>
> 3>If it can't be , then what design feature
> of the current LVM prevents it from supporting the above task?
>
> 4> Can any change in our product help us to solve this problem?
>
> 5>Moreover I think LVM on RedHat is working just by chance.
> I think pvscan depends on the order of the devices in the
> /proc/partitions , and hence when our pseudo devices are
> at the end of the /proc/paritions , pvscan shows our devices
> as active else it shows scsi as active.
>
> Is my inference correct?
Yes.
LVM2 is much more suitable to cover such vendor-specific configurations,
because it has configurable device name filters. LVM1 needs code changes
to support additional device name spaces.
>
> Regards
> Aditya Vasudevan
--
Regards,
Heinz -- The LVM Guy --
*** Software bugs are stupid.
Nevertheless it needs not so stupid people to solve them ***
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Heinz Mauelshagen Sistina Software Inc.
Senior Consultant/Developer Am Sonnenhang 11
56242 Marienrachdorf
Germany
Mauelshagen@Sistina.com +49 2626 141200
FAX 924446
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
_______________________________________________
linux-lvm mailing list
linux-lvm@sistina.com
http://lists.sistina.com/mailman/listinfo/linux-lvm
read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
