Install guide

defaults {

user_friendly_names yes

udev_dir /dev

polling_interval 10

selector "round-robin 0"

path_grouping_policy failover

getuid_callout "/sbin/scsi_id -g -u -s /block/%n"

prio_callout /bin/true

path_checker tur

rr_min_io 100

rr_weight priorities

failback immediate

no_path_retry fail

user_friendly_name yes

}

Now that the m ultipath.conf file is complete, try restarting the m ultipath service.

$ service multipathd restart

$ tail -f /var/l og/messages #Should see aliases listed

$ chkconfig multipathd on

Customers who want to push the envelope to have both performance and reliability might be surprised

to find that m ultibus is slower than failover in certain situations.

Aside from tweaking for things like failback or a faster polling_interval, the bulk of the recovery

latency is in the cluster take-over at the cluster and Oracle recover layers. If high-speed takeover is a

critical requirement, then consider using RAC

RAC/GFS Considerations

Because RAC (and therefore Clusterware) is certified for use with Red Hat Cluster Suite,

customers may chose a third configuration option of using either OCFS2 or ASM. This is an

unusual configuration, but this permits RAC/asm use, combined with the superior fencing of Red

Hat Cluster Suite. This configuration is not covered in this manual.

3.2.3. qdisk Configuration

A successful DM-Multipath configuration should produce a set of identifiable inodes in the

/dev/m apper directory. The /dev/mapper/qdisk inode will need to be initialized and enabled as a

service This is the one of the first pieces of info you need for the /etc/cluster.conf file.

$ mkqdisk –l HA585 –c /dev/mapper/qdisk

By convention, the label is the same name as the cluster; in this case, HA_585. The section of the

cluster.conf file looks like the following.

Red Hat Enterprise Linux 5 Configuration Example - Oracle HA on Cluster Suite