Linux Host Server Reboot Best Practices - Dell PowerVault MD3200i Owner's Manual

Blacklist Local Drive in Multi-path Driver
If your multipath drivers are connecting to storage area networks (SANs), it
may be useful to be able to exclude or "blacklist" certain devices in your
/etc/multipath.conf file. Blacklisting prevents the multipath driver from
attempting to use those local devices.
To blacklist a local drive or device:
1 Run the multipath -l command to determine the local drive or
device WWID (World-Wide Identifier) or vendor/model string.
2 Edit the /etc/multipath.conf file as follows:
blacklist {
wwid
...
}
or
blacklist {
device {
vendor
model model_string
};
NOTE:
image to include the updated configuration file by running the #dracut -force
command.
3 Reboot the host.

Linux Host Server Reboot Best Practices

It is recommended that you follow the procedures shown below when
rebooting your Linux host server using Device Mapper multipathing with an
MD3200i Series storage array.
1 Unmount all Device Mapper multipath device nodes mounted on the
server
# umount <mounted_multipath_device_node>
drive_wwid
vendor_string
RedHat version 6.0 and 6.1 users must rebuild the initramfs root file
Configuration: Device Mapper Multipath for Linux
195