Trying to get multipath working with BL460c & MSA2324sa

[BradV]

Hello,

I'm using RHEL 6 on the BL460c. I have 8 connections to the MSA and can see the 8 devices, /dev/cciss/c0d[0-7] for the volume presented. I can't seem to get multipathd to create a multipath device for it.

If I do a multipath -v3 -ll for example on one of the devices I see:

cciss!c0d7 not found in pathved
cciss!c0d7 mask = 0x5
cciss!c0d7 dev_t = 104:112
cciss!c0d7 size = 83886080
cciss!c0d7 subsystem = cciss
cciss!c0d7 h:b:t:l = 0:0:7:0
cciss!c0d7 vendor = HP
cciss!c0d7 product = MSA2324sa
cciss!c0d7 revision = M110
cciss!c0d7 get_state
cciss!c0d7 path_checker = tur (controller setting)
cciss!c0d7 checker timeout = 300000 ms (internal default)
cciss!c0d7 path offline
...
==== paths list ====
uuid hcil dev dev_t pri dm_st chk_st vend/prod/rev dev_st
0:0:0:0 cciss!c0d0 104:0 -1 undef faulty HP,MSA2324sa running
0:0:1:0 cciss!c0d1 104:16 -1 undef faulty HP,MSA2324sa running
0:0:2:0 cciss!c0d2 104:32 -1 undef faulty HP,MSA2324sa running
0:0:3:0 cciss!c0d3 104:48 -1 undef faulty HP,MSA2324sa running
0:0:4:0 cciss!c0d4 104:64 -1 undef faulty HP,MSA2324sa running
0:0:5:0 cciss!c0d5 104:80 -1 undef faulty HP,MSA2324sa running
0:0:6:0 cciss!c0d6 104:96 -1 undef faulty HP,MSA2324sa running
0:0:7:0 cciss!c0d7 104:112 -1 undef faulty HP,MSA2324sa running
0:0:0:0 sda 8:0 -1 undef ready HP,LOGICAL VOLUME running

This is a brand new installation.

Any thoughts as to what I might be missing?

Regards,

Brad

[Bhavnish Kamboj (BK)]

Hi Brad,

Failover support for Linux is with Device Mapper 4.0 or higher.

Try installing and then check.

[BradV]

Hi BK,

Not sure I am following. This is a fresh install of RHEL 6. The devive-mapper-multipath rpm is listed as 0.4.9-31.e16.x86_64. I would assume since this OS is only a couple of months old that this version of multipath is quite recent.

Regards,

Brad

[jpmartin]

Brad,

install the last HP Device Mapper kit, but the link seems to be missing, or edit the /etc/multipath.conf and insert the following:

device
{
vendor "HP"
product "MSA2012sa|MSA2312sa|MSA2324sa"
getuid_callout "/sbin/hp_scsi_id -g -u -n -s /block/%n"
prio_callout "/sbin/mpath_prio_alua /dev/%n"
hardware_handler "0"
path_selector "round-robin 0"
path_grouping_policy group_by_prio
failback immediate
rr_weight uniform
no_path_retry 18
rr_min_io 100
path_checker tur

}

then restart the multipath daemon.

The multipath -ll would be fine.

Jean-Pierre

[BradV]

Hi Jean-Pierre,

Well, the install didn't work because this is RHEL 6. However, I had copied over the multipath.conf file from one of my RHEL 5 systems. I adjusted the blacklist so that it removed the internal disks from consideration. The only difference in the device section you listed and what I have is the getuid_callout line. The installation script uses the built-in scsi_id utility instead of hp_scsi_id starting with RHEL 5.4. So, my line is:

getuid_callout "/sbin/scsi_id --whitelisted --replace-whitespace --device=/block/%n"

I have the kit, I'll copy the hp_scsi_id into /sbin and change that line to see if it makes a difference.

Regards,

Brad

[BradV]

Darn,

Didn't work. I see:

/sbin/hp_scsi_id exited with 1
error calling out /sbin/hp_scsi_id -g -u -n -s /block/cciss/c0d0

for each of the devices.

Regards,

Brad

[BradV]

Well, apparently HP stopped updating the enablement kit after RHEL 5.4. The latest version was 4.4.1. They have a document that explains how to use standard Linux device-mapper to work with HP storage devices. It is available at:

http://h20272.www2.hp.com/utility/document.aspx?docurl=Shared%20Documents/an/solutions_linux/Device_Mapper_Multipath_RG_2010_08_02.pdf

However, it is outdated. Because for the 2324sa, it says to use "/sbin/scsi_id -g -u ..." and those parameters are not supported for this version of scsi_id.

Regards,

Brad

[Zygmunt Krawczyk]

For this configuration (P700m, SAS switch, MSA2324sa) the only working multipathing solutions are for Windows Server (MPIO) and for VMware. VMware uses hpsa driver for P700m, not cciss. HP develops hpsa driver to be widely available with verious linux, but unfortunately they gave up P700m support in hpsa.

[BradV]

Darn, I wonder why the sales engineer recommended that we go with SAS then instead of FC? That means all the redundant paths are pretty much useless?

Thanks for the information!

Regards,

Brad

[BradV]

OK, I have an update. Apparently RHEL 6 isn't certified on the MSA2324sa yet. They hope in a few months. In the meantime, I was trying with RHEL 5. That wasn't working. After installing RHEL 5.6 and then installing the HPDMultipathEnablementKit 4.4.1, it still didn't work. I then applied the PSP 8.60 for Linux and the BL460C G6 and it started working! So, install the latest enablement kit and the latest PSP for your setup. :)