Scanning For New Devices Without Rebooting - Novell LINUX ENTERPRISE SERVER 10 SP2 - STORAGE ADMINISTRATION GUIDE 05-15-2009 Administration Manual

/etc/init.d/boot.multipath start
/etc/init.s/multipathd start
5 After the multipathing services are started, verify that the software RAID's component devices
are listed in the
/dev/disk/by-id
Devices Are Listed: The device names should now have symbolic links to their Device
Mapper Multipath device names, such as
Devices Are Not Listed: Force the multipath service to recognize them by flushing and
rediscovering the devices.
To do this, enter the following commands:
multipath -F
multipath -v0
The devices should now be listed in
Device Mapper Multipath device names. For example:
lrwxrwxrwx 1 root root 10 Jun 15 09:36 scsi-mpath1 -> ../../dm-1
6 Restart the
boot.md
/etc/init.d/boot.md start
7 Check the status of the software RAID by entering
mdadm --detail /dev/mapper/mpath0
The RAID's component devices should match their Device Mapper Multipath device names
that are listed as the symbolic links of devices in the
8 Make a new
initrd
RAID services on reboot. Enter
mkinitrd -f mpath
9 Reboot the server to apply these post-install configuration settings.
10 Verify that the software RAID array comes up properly on top of the multipathed devices by
checking the RAID status. Enter
mdadm --detail /dev/mapper/mpath0
For example:
Number Major Minor
0 253
1 253
2 253
5.10 Scanning for New Devices without
Rebooting
If your system has already been configured for multipathing and you later need to add more storage
to the SAN, use the following procedure to scan the devices and make them available to
multipathing without rebooting the system.
1 On the storage subsystem, use the vendor's tools to allocate the device and update its access
control settings to allow the Linux system access to the new storage. Refer to the vendor's
documentation for details.
directory. Do one of the following:
/dev/disk/by-id
service and the RAID device by entering
to ensure that the Device Mapper Multipath services are loaded before the
RaidDevice State
0 0 active sync
1 1 active sync
2 2 active sync
.
/dev/dm-1
, and have symbolic links to their
/dev/disk/by-id
/dev/dm-0
/dev/dm-1
/dev/dm-2
Managing Multipath I/O for Devices
directory.
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