Linux recognizes 2 SAN drives instead of 1 - StorageWorks P2000 + Redhat 5U7

[c_k]

Hi, 

I will try to explain this as much as i can since i am not a SAN expert, i was found caught up in the installation and configuration of a SAN system, something i had no prior experience with as i come from a software development background.

I have the following environment now :

2 nodes with Redhat 5 update 7 64 bits

a StorageWorks P2000 G3 SAN system with 4 disks on which a RAID 10 virtual disk and a single volume were created.

an HP SAN fibre switch connecting the servers to the SAN with 2 controllers of the SAN connected to the switch

I installed the following rpms on linux 

HP SC08e 6GB 2-ports Ext PCIe SAS Host Bus Adapter for Linux : mpt2sas-5.10.05.00-2.rhel5.x86_64 

and 

HP fiber channel utility for Linux: fibreutils-3.2-3.x86_64

are these the right drivers that i need to install? the problem is that in my Linux i see two identical devices /dev/sda and /dev/sdb. It's like the system is seeing the disk twice, once through each of the connected controllers of the SAN.

ideas and insights much appreciated

[Johan Guldmyr]

Hi!

SC08e is a SAS card.

I don't think that rpm will help you.

What kind of HBA do you have in the servers?

What kind of servers is it?

If you can see the disks then the drivers are probably OK, but you may want to double-check what drivers is installed with what is available, maybe newer driver/hba firmware is advisible.

You need to configure multipathing on the servers.

On our SLC 5.1 it is done in /etc/multipath.conf

[Sebastian.Koehler]

You need to setup devicemapper-multipath for this to work. It acts like a filter driver handling multiple path to P2000 G3 SAS. Once configured, you have to work with the mpath devices it provides.

Regards,

Sebastian

[c_k]

Hi and thanks for the reply,

I have a Proliant DL 380 G7 server, i tried the folllowing and got :

[root@srvdb01 ~]#cat /sys/class/scsi_host/host2/device/fc_host\:host2/device/scsi_host\:host2/model
Brocade-825

[root@srvdb01 ~]#cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
  Vendor: hp       Model: DVD A  DS8A5LH   Rev: 1HE3
  Type:   CD-ROM                           ANSI SCSI revision: 05
Host: scsi3 Channel: 00 Id: 00 Lun: 00
  Vendor: HP       Model: P2000 G3 FC      Rev: T230
  Type:   Direct-Access                    ANSI SCSI revision: 05
Host: scsi3 Channel: 00 Id: 01 Lun: 00
  Vendor: HP       Model: P2000 G3 FC      Rev: T230
  Type:   Direct-Access                    ANSI SCSI revision: 05

so if i am not wrong i think i have Brocade FC HBAs. where can i find the appropriate driver?

Thanks

[Johan Guldmyr]

Hey, so the Brocade-825 - is that the HP 82B card?

http://h20000.www2.hp.com/bizsupport/TechSupport/DriverDownload.jsp?lang=en&cc=us&prodNameId=3954652&taskId=135&prodTypeId=12169&prodSeriesId=3662826&lang=en&cc=us

If so, the above link should be able to help you.

bcu is Brocade's CLI tool for their HBAs that you can use for some troubleshooting / diagnosing of the hba.

[c_k]

Hi and thanks again for the insight, yeah it is the HP SorageWorks 82B Fibre Channel Controller, at least that's what i see in the BIOS.

so i found the driver on the HP website on the following page

http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareDescription.jsp?lang=en&cc=us&prodTypeId=12169&prodSeriesId=3662826&prodNameId=3954652&swEnvOID=4004&swLang=13&mode=2&taskId=135&swItem=co-99230-1

I installed it and still it's the same problem.

@Johan Guldmyr wrote:

Hey, so the Brocade-825 - is that the HP 82B card?

http://h20000.www2.hp.com/bizsupport/TechSupport/DriverDownload.jsp?lang=en&cc=us&prodNameId=3954652&taskId=135&prodTypeId=12169&prodSeriesId=3662826&lang=en&cc=us

If so, the above link should be able to help you.

bcu is Brocade's CLI tool for their HBAs that you can use for some troubleshooting / diagnosing of the hba.

[Johan Guldmyr]

yes, that's because you need to set up the multipathing / devicemapper that the 3rd poster wrote about.

[c_k]

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@Sebastian.Koehler wrote:

You need to setup devicemapper-multipath for this to work. It acts like a filter driver handling multiple path to P2000 G3 SAS. Once configured, you have to work with the mpath devices it provides.

Regards,

Sebastian

---

Hi can you please post a link to the document you attached. i could not download it.

thank you to all those who contributed, your help was priceless

[Johan Guldmyr]

http://www.hp.com/go/devicemapper

select your OS, select your driver, click on 'release notes'. There is an installation guide.