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127Administering dynamic multipathing (DMP)
How DMP works
Figure 3-1 How DMP represents multiple physical paths to a disk as one node
As described in “Enclosure-based naming” on page 23, VxVM implements a disk
device naming scheme that allows you to recognize to which array a disk
belongs. Figure 3-2, shows an example where two paths, c1t99d0 and c2t99d0,
exist to a single disk in the enclosure, but VxVM uses the single DMP node,
enc0_0, to access it.
Figure 3-2 Example of multipathing for a disk enclosure in a SAN environment
Multiple paths
Single DMP node
DMP
VxVM
Mapped by DMP
Multiple paths
Host
Disk
c2c1
Mapped by DMP
Host
Fibre Channel hubs
or switches
Disk enclosure enc0
enc0_0
DMP
VxVM
c1t99d0 c2t99d0
c2c1
Disk is c1t99d0 or c2t99d0
depending on the path