XtendLan xl-raid-2804issa, Installation And Configuration Manual

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and the data in it just like it finished rollback. At the same time, the other related snap
UDV(s) can not be accessed.
4. After rollback process finished, the other related snap UDV(s) will be deleted, and
snapshot space will be set to
0
.
IMPORTANT! Before executing rollback, it is better to dismount file
system for flushing data from cache to disks in OS first.
4.5 Disk Roaming
Physical disks can be re-sequenced in the same system or move whole physical disks from system-
1 to system-2. This is called disk roaming. Disk roaming has some constraints as described in the
following:
1. Check the firmware of two systems first. It is better that both have same firmware
version or newer.
2. Whole physical disks of related VG should be moved from system-1 to system-2
together. The configuration of both VG and UDV will be kept but LUN configuration will
be cleared to avoid conflict with system-2.
4.6 Support Microsoft MPIO and MC/S
MPIO (Multi-Path Input/Output) and MC/S (Multiple Connections per Session) both use multiple
physical paths to create logical "paths" between the server and the storage device. In the case
which one or more of these components fails, causing the path to fail, multi-path logic uses an
alternate path for I/O so that applications can still access their data.
Microsoft iSCSI initiator supports multi-path function. Please follow the procedures to use MPIO
feature.
1. A host with dual LAN ports connects cables to XL-RAID-2804ISSA .
2. Create a VG/UDV, attach this UDV to the host.
3. When installing
“Microsoft iSCSI initiator”
, please install MPIO driver at the same
time.
4. Logon to target separately on each port. When logon to target, check “Enable multi-
path”. Please refer to Appendix D, step 6.
5. MPIO mode can be selected on Targets

Details

Devices

Advanced.
6. Rescan disk.
7. There will be one disk running MPIO.