Configure Luns in rhel.4.4

[AnthonySN]

We have presented one vdisk of 100GB from an EVA3000(vcs2.02) to two rx6600 (rhel4.4).
We can see the vdisk with the path /dev/sda and /dev/sdb.
we want to present this to oracle10g rac as raw disk.
In rhel 3 we had securepath which will give us one path say /dev/sdh which in turn will point to /dev/sda and as well as /dev/sdb.

but since we do need securepath in rhel4.4
which is the path we should specify during oraclerac installation.
or what is the configuration file we need to update/modify to give us a single name/path.

[Steven E. Protter]

Shalom,

You do not need secure path to make LUNS available to Linux.

You need to intall cpqacu from the DL300 series smart start pack. This will permit you to connect to the system via an httpd interface and configure the disk. This is the procedure for non-managed disk arrays.

Alternately and somewhat easier is to take the WWN World Wide Number of your HBA/Fiber Card and program it into a LUN configured on the EVA-3000 control station. This control station is normally a DL-380 system running windows server 2003.

After configuration and presentation, boot the Linux system, after boot you should see the LUN on fdisk -l

The smart start pack has a utility call hpscan which will scan for presented disks and tell you their addresses.

SEP

[AnthonySN]

sep,
we are able to see the 2 paths
/dev/sda and /dev/sdb
but we want a common path for configuring oraclerac, so how do we configure a single path wihout securepath.

[Ivan Ferreira]

Use the qlogic driver with multipath support as described in the attached document.

[slydmin]

This is how we had it setup:

use udev for persistent naming along with multipath

Files required to be modified:
1. /etc/multipathd.conf

add your disk names in this file
eg:
multipath {
wwid 360060e80141a840000011a8400000002
alias oradsk_01d
}

2. make sure your multipathd starts automatically (chkconfig multipathd on)

3. edit /etc/sysconfig/rawdevices to something like:
/dev/raw/raw1 /dev/mapper/oradsk_01d1
/dev/raw/raw2 /dev/mapper/oradsk_02d1


4. Udev is needed for keeping the permissions correct on raw devies
eg
# OCR file
raw/raw[1-2]:root:oinstall:0640
# VotingDisk file
raw/raw[3-5]:oracle:oinstall:0640


please read the attached white paper from Oracle.

hth,
-s

[AnthonySN]

We installed hp-lpfc-2007-06-19.tar.gz
for emulex cards since our the hba cards are not qlogic.
but finding it difficult how to configure to have single path instead of 2 paths to the same disk

we tried installing HPDMmultipath-4.0.0 but it doesnt install saying the version is not supported.

slydmin,
we dont have multpath installed so editing /etc/multipath.conf is not usefull.

let me know if any other alternative.

[AnthonySN]

We have updated the OS to RHEL 5 update 1.
and are able to install HPDMmultipath-4.0.0 now.

But the doc provided with HPDMmultipath-4.0.0 is not that clear as to how to do the configuration for single path.

[AnthonySN]

Use DMP