MSA1000 SSP query

 
PaulW123
Occasional Advisor

MSA1000 SSP query

Hi all,

I'm trying to use SSP to connect two servers to separate logical drives in my SAN, but I'm hitting a curious problem.

My setup is:
MSA 1000 (firmware v4.48)
MSA Hub 2/3
2 x HP DL 360G3 Servers (2GB RAM, Embedded 5i Controller, Windows 2003 R2 Std with SP2)
2 x FC2143 HBA
Servers built using SmartStart v8.20, PSP v8.20 applied following installation.

I have 4 logical drives configured via ACU (v8.25.5.0). Again via ACU I have enabled SSP allocating drives 1 and 2 to Server1 and
drives 3 and 4 to Server2.

All appears to be working fine (Server2 cannot see the volumes assigned to Server1 and vice versa). The problem appears when either of the servers is restarted. If Server1 is restarted, at the BIOS startup (prior to the OS loading) the MSA1000 controller appears to be reset / reinitialised. This results in the logical drives allocated to Server2 being temporarily unavailable, leading to Windows System errors :

"The device 'HP MSA1000' (SCSI\Array&Ven_COMPAQ&Prod_MSA1000&Rev_4.48\4&1713bd34&0&000000) disappeared from the system without first being prepared for removal."
and
"The system failed to flush data to the transaction log. Corruption may occur."

The curious bit is that this seems to occur as the Embedded 5i Controller is initialising.

Is this expected behaviour ? Am I missing something fundamental ?

Any ideas or suggestions will be greatly appreciated.

Thanks for your help
Cheers
Paul.

9 REPLIES 9
Torsten.
Acclaimed Contributor

Re: MSA1000 SSP query

FW 4.48 is active/passive - do you have the correct multipathing software installed?

Hope this helps!
Regards
Torsten.

__________________________________________________
There are only 10 types of people in the world -
those who understand binary, and those who don't.

__________________________________________________
No support by private messages. Please ask the forum!

If you feel this was helpful please click the KUDOS! thumb below!   
Uwe Zessin
Honored Contributor

Re: MSA1000 SSP query

The problem is that the 2/3 hub does not offer proper isolation. Any restart of a server disrupts the traffic on the arbitrated loop for a short time.

Did you assign a hard-assigned AL_PA with a relatively high value for the MSA?
.
PaulW123
Occasional Advisor

Re: MSA1000 SSP query

Thanks for your reply Torsten.

I've not knowingly applied any multipathing software. I've applied PSP v8.20 but I don't think multipathing software was installed as part of that.

I thought I'd only need multipathing software if I was clustering the servers - is this not the case ?
PaulW123
Occasional Advisor

Re: MSA1000 SSP query

Thanks Uwe for posting.

I've not manually assigned an AL_PA. According to the ACU the MSA1000 controller is using

Arbitrated Loop Physical Address Domain : 0, Area : 0, Port : 0

Do I need to change this ? I can't see how I'd configure this via the ACU.
PaulW123
Occasional Advisor

Re: MSA1000 SSP query

Hi,

Think I've found the problem. HP Support Document c01489928 :

http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&taskId=110&prodSeriesId=377751&prodTypeId=12169&prodSeriesId=377751&objectID=c01489928

It's an issue where 4GB HBAs are used. I'm not too happy about the solution (to use 2GB HBAs), but I guess there is little I can do about that!

Thanks for your help anyway folk. Anyone want to swap a couple of 4GB HBAs for 2GB cards ? :)

Regards
Paul.
Uwe Zessin
Honored Contributor

Re: MSA1000 SSP query

Paul,
the advisory is talking about a 4Gbit SFP (that is the electrical/optical tranceiver module) _within_ the 2/3 hub, not an external adapter. I assume you have locked the adapter speed to 2 Gbit already?

> 0, Area : 0, Port : 0

No, that is not a valid AL_LPA, but maybe the output from ACU is wrong. As far as I can tell, hard-addressing can only be chosen from the command line.
.
Greybeard
Esteemed Contributor

Re: MSA1000 SSP query

Hi Paul, why not get a cheap 8 port SAN switch and put it between the servers and the MSA, this should prevent interuption to the loop on the internal hub. I've also seen issues with the POST laser test pulse from some HBAs that occours prior to the FLOGI PLOGI phase so this would also be taken care of. I got an IBM FC8 for 40 bucks online!
_________________________________________________
How to assign points on this new forum? Click the Kudos Star!
PaulW123
Occasional Advisor

Re: MSA1000 SSP query

Apologies for not replying sooner, I've been away from work. Thanks everyone for the feedback.

Uwe - I think this link better describes what I think is my problem:
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?lang=en&cc=us&objectID=c00625693&prodTypeId=12169&prodSeriesId=377751
Different HBA's but exactly the same symptoms.

Larry - thats a good idea. However I actually have a spare MSA100 SAN lying around so rather than use SSP I'm just going to use both SANs.

Thanks all!

PaulW123
Occasional Advisor

Re: MSA1000 SSP query

Closing Thread.