Instead of installing the original device-mapper-multipath package there is a simillar package from HP called HPDMmultipath-[version].tar.gz that has already a configuration for HP EVA and XP storage devices. The HPDMmultipath-[version].tar.gz can be downloaded from www.hp.com
# tar -zxvf HPDMmultipath-3.0.0.tar.gz
# cd HPDMmultipath-3.0.0/RPMS
# rpm -ivh HPDMmultipath-tools[version]-[Linux-Version]-[ARCH].rpm
# vim /etc/multipath.conf
defaults {
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 uniform
failback immediate
no_path_retry 12
user_friendly_names yes
}