ESXi hosts can
use multipathing for failover. With some storage devices,
ESXi hosts can
also use multipathing for load balancing.
To achieve better load
balancing across paths, administrators can specify that the
ESXi host
should switch paths under specific circumstances. Different options determine
when the
ESXi host
switches paths and what paths are chosen. Only a limited number of storage
arrays support round robin.
You can use
esxcli storage
nmp psp roundrobin to retrieve and set round robin path options on a
device controlled by the
roundrobin PSP. Specify one of the options listed in
Connection Options for ESXCLI Host Management Commands
in place of
<conn_options>.
Procedure
-
Retrieve path
selection settings for a device that is using the
roundrobin PSP.
esxcli <conn_options> storage nmp psp roundrobin deviceconfig get --device na.xxx
-
Set the path selection.
You can specify when the path should change, and whether unoptimized paths
should be included.
- Use
--bytes or
--iops to specify when the path should change, as
in the following examples.
esxcli <conn_options> storage nmp psp roundrobin deviceconfig set --type "bytes" -B 12345 --device naa.xxx
Sets the device specified by
--device to switch to the next path each time
12345 bytes have been sent along the current path.
esxcli <conn_options> storage nmp psp roundrobin deviceconfig set --type=iops --iops 4200 --device naa.xxx
Sets the device specified by
--device to switch after 4200 I/O operations have
been performed on a path.
- Use
useano to specify that the round robin PSP should
include paths in the active, unoptimized state in the round robin set (1) or
that the PSP should use active, unoptimized paths only if no active optimized
paths are available (0). If you do not include this option, the PSP includes
only active optimized paths in the round robin path set.