All versions of Red Hat Enterprise Linux 5 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.
You can use the sample Red Hat Enterprise Linux 5 series configuration files shown here to create your own multipath.conf file. When you create your file, keep the following in mind:
Red Hat Enterprise Linux 5 series notes | Explanation |
---|---|
Blacklist section | You must provide information of your system in the blacklist section. Any names shown in the sample files are examples and will not work with your system. |
SAN boot LUNs and the user_friendly_names parameter | NetApp recommends that you set the user_friendly_names parameter to no. There have been reports of problems when this parameter is set to yes. |
Red Hat Enterprise Linux 5 prior to Update 6 | If you are using a version of Red Hat Enterprise Linux 5 series prior to update 6, check the Recommended Host Settings for Linux Host Utilities to see if there are any parameter values specific to that version. |
When you create a SAN boot LUN, the installer sets the user_friendly_names parameter to yes by default. NetApp recommends that you set the user_friendly_names parameter to no. There have been reports of problems when this parameter is set to yes.
If you create a SAN boot LUN and the installer sets the user_friendly_names parameter to yes, you must perform the following steps.
You could use the following command line: mkinitrd -f /boot/initrd-"`uname -r`".img `uname -r`
For example, suppose the name of the root device is /dev/mapper/mpatha and the WWID of the device is 360a98000486e2f66426f583133796572. You must recreate the initrd-image. Then you must change the device name to /dev/mapper/360a98000486e2f66426f583133796572 in /etc/fstab and /boot/grub/device.map and any other place that that refers to device /dev/mapper/mpatha. After that, reboot the host.
The following file provides an example of the values you need to supply when your host is running Red Hat Enterprise Linux 5 with update 10, 9, 8 or update 7 and has ALUA enabled.
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
flush_on_last_del yes
max_fds max
pg_prio_calc avg
}
# All data under blacklist must be specific to your system.
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"
path_grouping_policy group_by_prio
features "3 queue_if_no_path pg_init_retries 50"
prio_callout "/sbin/mpath_prio_alua /dev/%n"
path_checker tur
path_selector "round-robin 0"
failback immediate
hardware_handler "1 alua"
rr_weight uniform
rr_min_io 128
getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
}
}
The following file provides an example of the values you need to supply when your host is running Red Hat Enterprise Linux 5 with update 10, 9, 8, or update 7 and does not have ALUA enabled.
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
flush_on_last_del yes
max_fds max
pg_prio_calc avg
}
# All data under blacklist must be specific to your system.
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"
path_grouping_policy group_by_prio
features "3 queue_if_no_path pg_init_retries 50"
prio_callout "/sbin/mpath_prio_ontap /dev/%n"
path_checker tur
path_selector "round-robin 0"
failback immediate
hardware_handler "0"
rr_weight uniform
rr_min_io 128
getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
}
}
The following file provides an example of the values you need to supply when your host is running Red Hat Enterprise Linux 5 with update 6 and has ALUA enabled:
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
flush_on_last_del yes
max_fds max
pg_prio_calc avg
}
# All data under blacklist must be specific to your system.
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"
path_grouping_policy group_by_prio
features "1 queue_if_no_path"
prio_callout "/sbin/mpath_prio_alua /dev/%n"
path_checker directio
path_selector "round-robin 0"
failback immediate
hardware_handler "1 alua"
rr_weight uniform
rr_min_io 128
getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
}
}
The following file provides an example of the values you need to supply when your host is running Red Hat Enterprise Linux 5 with update 6 and does not have ALUA enabled.
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
flush_on_last_del yes
max_fds max
pg_prio_calc avg
}
# All data under blacklist must be specific to your system.
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"
path_grouping_policy group_by_prio
features "1 queue_if_no_path"
prio_callout "/sbin/mpath_prio_ontap /dev/%n"
path_checker directio
path_selector "round-robin 0"
failback immediate
hardware_handler "0"
rr_weight uniform
rr_min_io 128
getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
}
}