Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

137Administering dynamic multipathing (DMP)
Administering DMP using vxdmpadm
emcpower10 auto:sliced disk1 ppdg online
emcpower11 auto:sliced disk2 ppdg online
emcpower12 auto:sliced disk3 ppdg online
emcpower13 auto:sliced disk4 ppdg online
emcpower14 auto:sliced disk5 ppdg online
emcpower15 auto:sliced disk6 ppdg online
emcpower16 auto:sliced disk7 ppdg online
emcpower17 auto:sliced disk8 ppdg online
emcpower18 auto:sliced disk9 ppdg online
emcpower19 auto:sliced disk10 ppdg online
The following command displays the paths that DMP has discovered, and which
correspond to the PowerPath-controlled node, emcpower10:
# vxdmpadm getsubpaths tpdnodename=emcpower10
NAME TPDNODENAME PATH-TYPE[-]DMP-NODENAME ENCLR-TYPE ENCLR-NAME
===================================================================
c7t0d10 emcpower10s2 - emcpower10 EMC EMC0
c6t0d10 emcpower10s2 - emcpower10 EMC EMC0
Conversely, the next command displays information about the PowerPath node that
corresponds to the path, c7t0d10, discovered by DMP:
# vxdmpadm gettpdnode nodename=c7t0d10
NAME STATE PATHS ENCLR-TYPE ENCLR-NAME
===================================================================
emcpower10s2 ENABLED 2 EMC EMC0
Gathering and displaying I/O statistics
You can use the vxdmpadm iostat command to gather and display I/O statistics for a
specified DMP node, enclosure, path or controller.
To enable the gathering of statistics, enter this command:
# vxdmpadm iostat start [memory=size]
To reset the I/O counters to zero, use this command:
# vxdmpadm iostat reset
The memory attribute can be used to limit the maximum amount of memory that is used
to record I/O statistics for each CPU. The default limit is 32k (32 kilobytes) per CPU.
To display the accumulated statistics at regular intervals, use the following command:
# vxdmpadm iostat show {all | dmpnodename=dmp-node | \
enclosure=enclr-name | pathname=path-name | ctlr=ctlr-name} \
[interval=seconds [count=N]]
This command displays I/O statistics for all controllers (all), or for a specified DMP
node, enclosure, path or controller. The statistics displayed are the CPU usage and amount
of memory per CPU used to accumulate statistics, the number of read and write
operations, the number of kilobytes read and written, and the average time in milliseconds
per kilobyte that is read or written.