RedHat4 U4 and EVA 4000

[DJEFEL DJILALI]

Dear all,

We have purchased recently 2 HP servers DL 580 G4 + 9TB disk storage and currently we are facing some problems…

Each server has got two HBA 4GB Fibre Channel adapters, and each card is connected to 02 EVA4000 controllers through 02 SAN switches. This architecture present a high level of redundancy as each server can access the disk storage through 4 different paths.

Initially we bought the servers with Linux Red Hat Version 3 Update 3 plus the “Secure Path 3.0C” software supposed to manage automatically the Multipathing, the load balancing and the Failover functionalities... but we installed Red Hat Enterprise Linux AS V4 U4. Unfortunately Secure Path is not compatible with Red Hat V4 U4, and by consequence couldn't be installed.

Failing to install Secure Path on Red Hat V4 U4 we can not take advantage of all the redundancy that our platform offers, in case of any path failure we must mount our disks manually on an other path instead of the automatic Failover. In addition to that, the Load balancing wouldn't be used.

However, we have been told that all the functionalities of Secure Path (Multipathing+ Failover + Load Balancing) are integrated as tools in the Qlogic drivers. We would like to ask you to confirm that and also to tell us how to use these tools.

Can you please provide us this driver and show us how to configure it?

Currently we can view our disk volumes trough 4 different paths (2 FC cards on the server + 2 controllers in the disk storage). At a certain moment, we will mount this disk on the system with one path. If ever this path fails (let say an FC adaptor is failed), what tool will allow the system to use an other path to access the disk?

I mean concretely what tool will mount automatically the other path? And what actions are pre-required to enable this?

Your quick response would be highly appreciated

Thanks and regards,
Djilali

[Rob Leadbeater]

Hi,

You don't mention specifically which HBAs you have, but I think the drivers available here:

http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=12169&prodSeriesId=439556&prodNameId=315741&swEnvOID=2025&swLang=8&mode=2&taskId=135&swItem=co-43431-2

will probably help.

Install this package and everything should work. Just check the install notes to ensure you select the failover option when installing.

Hope this helps,

Regards,

Rob

[Van den Broeck Tijl]

The drivers do tend to differ upon your HBA, but generally the module is qla2xxx. Make sure all modules are loaded (it does have some dependancies)

The tool required to configure everything is called "SANSurfer". Could be in a separate package, search the HP site for it. Make sure you've got portmap running and such, SANSurfer uses RPC for connections towards the qlremote daemon.


But please before installing the driver, check that the stock kernel+modules does not already support it? I doubt it for RHES4, but RHES5 does have stock Qlogic HBA support with Multipath & failover using the open source package multipath-tools, way better than SANSurfer imho.

[DJEFEL DJILALI]

Hi,

Thanks for your prompt reply.

We had already installed exactly the same hp_qlogic driver you have just sent.

What happened with this one is, that after its installation, the original redhat_qlogic driver has been overwritten and the HBA card could not work proprely. We had to reinstall completely the Linux OS, to get the HBA card working again.

So, now we are afraid if we do the same, to have the same problem.

FYI, the HBA card is QLA 2422, PN: AB429A

Please advice.

Djilali

[Van den Broeck Tijl]

I checked for RHEL4U4, Please see http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=967773
multipath + loadbalancing works with stock drivers since RHEL4U2.



Make sure you have the following packages installed :
device-mapper
device-mapper-multipath
multipath-tools

[Hagmann Mike]

Hi Djilali

For me is not clear that you see every Path with RHEL4ASU4, normaly RHEL4ASU4 would arrange that automatic for you ( with device-mapper multipath ) Do you really boot with the RHEL4ASU4 Boot CD?

We have here arrount 60 Server's with RHEL4ASU4 ( 64bit ) and the HP Qlogic driver, and it works wihout problems.

What Firmware do you have on the EVA4000? That's really important ( check also with the Howto ) .

To your Problem, since RHEL4ASU4 device-mapper / multipath work with EVA, is all supported, but HP says "do not use it in Mission Critical Enviroment" --> see howto.

The Installation is really good described in the following Howto ( I also att. it ) :

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00814876/c00814876.pdf

you can also use the fully supported qlogic solution ( but with that you have only a failover solution)

Maybe the easiest way for you is to download the Proliant Support Pack:

http://h18023.www1.hp.com/support/files/server/us/download/25259.html

or here is the Qlogic Driver from HP

http://h18023.www1.hp.com/support/files/server/us/download/24597.html

here are all Drivers for your Server ( !! 64bit !! )

http://h18023.www1.hp.com/support/files/server/us/locate/1117_6222.html

When you have any question feel free to contact me.

good luck

regards mike

[DJEFEL DJILALI]

Hi all,

This is to let you know that the problem has been fixed. We managed to fix it by doing the following:
1- Install the development kernel from the Redhat CDs (release 42)
2- Upgrade it to the the release 55 (download file got from the web)
3- Install qlogic in failover mode.

Thanks for your support,
Djilali