Application Notes Linux Device Mapper Multipath with Data Replication Solutions for HP StorageWorks EVA and XP disk arrays (5697-7807, October 2008)

#echo 1 > /sys/block/<SCSI device>/device/rescan
4. Create multipath device for the LU with the new host access permission.
#multipath –v0
Continuous Access operations
Data replication across data centers located miles apart is a desirable feature, given the size of the data
and their criticality. This replication of data across geographically distant locations is provided by
Continuous Access for HP StorageW orks disk array s. Linux Device Mapper Multipath provides support for
remote data replication through this solution. Figure 2 shows a Typical remote replication configuration.
Figure 2 A t ypi cal remote rep lica tion configuration
Creat
ing Data Replication groups
Data R
eplication (DR) groups are the fundamental units of remote data replication. A D R group is created
on the
array to associate a set of source Vdisk with the destination site. Vdisks in the destination site
can be accessed for read-only operations. The destination Vdisk can be presented to a host and Device
Mapper M ultipath device is created with appropriate host access permissions. However, the d estination
Vdis
k should not be presented to the same host, to which the source Vdisk is presented.
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