All versions of Red Hat Enterprise Linux 4 series use a DM-Multipath configuration file, but there might be slight variations in the file based on which Red Hat update you have installed. You can replace your current file with this sample file and change the values to ones that are appropriate for your system.
Please review the following configuration notes before you set up your configuration file to enable DM-Multipath on Red Hat Enterprise Linux 4 series:
Red Hat Enterprise Linux 4 series version | Parameter Notes |
---|---|
4 Update 7 or later |
|
(iSCSI only) 4 Update 7 and earlier | In environments running iSCSI, set path_grouping_policy to multibus |
4 Update 7 and earlier | Place rr_min_io in the default section, not the device section, of the multipath.conf file and set its value to 128. |
4 Update 6 and earlier | Set pathchecker to readsector0 . |
The following file provides an example of the values you need to supply when your host is running Red Hat Enterprise Linux 4 Update 9.
Remember: If you use the blacklist section, you must replace the sample information with information for your system.
defaults
{
user_friendly_names no
queue_without_daemon no
max_fds max
flush_on_last_del yes
}
# All data under blacklist must be specific to your system.
devnode_blacklist
{
devnode "^hd[a-z]"
devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
devnode "^cciss.*"
}
devices
{
device
{
vendor "NETAPP"
product "LUN"
getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
prio_callout "/sbin/mpath_prio_ontap /dev/%n"
features "1 queue_if_no_path"
hardware_handler "0"
path_grouping_policy group_by_prio
path_selector "round-robin 0"
failback immediate
rr_weight uniform
rr_min_io 128
path_checker directio
}
}