Installation guide

2. Obtain unique SCSI disk identifiers of the Clusterware devices:
# for i in `awk '/sd/ {print $4}' /proc/partitions`; \
do echo "$i: `scsi_id -g -u -s /block/$i`"; done
These identifiers are required to create persistent device names.
3A. Creating persistent raw devices for single path LUNs
Red Hat Enterprise Linux 4 had a rawdevices service and the /etc/sysconfig/rawdevices file for bind-
ing raw devices to block devices. Red Hat Enterprise Linux 5 has deprecated raw devices. However, it is possi-
ble to use the udev facility to configure raw devices and set their permissions.
On Red Hat Enterprise Linux 5 system, the util-linux package provides the default udev raw mapping file
/etc/udev/rules.d/60-raw.rules.
Create a custom udev raw mapping rule file, /etc/udev/rules.d/61-oracleraw.rules. For exam-
ple, for unpartitioned block device with WWID=360a98018486f6959684a45333527173 add the following rule:
# Raw bind to unpartitioned Oracle Clusterware devices
ACTION=="add", KERNEL=="sd*[!0-9]", PROGRAM=="/sbin/scsi_id -g -u -s %p",
RESULT=="360a98018486f6959684a453333527173", RUN+="/bin/raw /dev/raw/raw1 %N"
This will create the raw device /dev/raw/raw1 that will be persistently bound to the LUN with the specified
WWID.
Test the udev configuration with the udevtest utility:
# udevtest /block/sda | grep raw
If the block device is partitioned the rule should look like:
# Raw bind to partitioned Oracle Clusterware devices
ACTION=="add", KERNEL=="sd*[0-9]", PROGRAM=="/sbin/scsi_id -g -u -s %p",
RESULT=="360a98018486f6959684a453333527173", RUN+="/bin/raw /dev/raw/raw%n %N"
This will create raw devices /dev/raw/raw1, /dev/raw/raw2, etc. for each partition on the LUN and
they will be persistently bound to the LUN with the specified WWID.
To test the configuration run, for example,
# udevtest /block/sda/sda1 | grep raw
Finally, to actually create the raw devices, use the start_udev command:
# start_udev
Starting udev: [OK]
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