Customizing Round Robin Setup

You can use the esxcli storage nmp psp roundrobin commands to set round robin path options on a device controlled by the VMW_PSP_RR PSP.

Specifying and Customizing Round Robin Path Policies

You can use esxcli storage nmp commands to set path policies. Specify one of the options listed in Connection Options for vCLI Host Management Commands in place of <conn_options>.

Set the path policy to round robin.

esxcli <conn_options> storage nmp device set --device naa.xxx --psp VMW_PSP_RR

Specify when to switch paths.
You can choose the number of I/O operations, number of bytes, and so on. The following example 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 "bytes" -B 12345 --device naa.xxx
```
The following example sets the device specified by --device to switch after 4200 I/O operations have been performed on a path.
```
esxcli <conn_options> storage nmp psp roundrobin deviceconfig set --type=iops --iops 4200 --device naa.xxx
```

Retrieving Path Selection Settings

The esxcli storage nmp psp roundrobin deviceconfig get command retrieves path selection settings for a device that is using the roundrobin PSP. You can specify the device to retrieve the information for.

Options Description

Options	Description
`-d <device>` `--device <device>`	Device to get round robin properties for.

-d <device>

--device <device>

Device to get round robin properties for.

Specifying Conditions for Path Changes

The esxcli storage nmp psp roundrobin deviceconfig set command specifies under which conditions a device that is using the VMW_PSP_RR PSP changes to a different path. You can use --bytes or --iops to specify when the path should change.

Options	Description
`--bytes` `-B`	Number of bytes to send along one path for this device before the PSP switches to the next path. You can use this option only when `--type` is set to bytes.
`--device` `-d`	Device to set round robin properties for. This device must be controlled by the round robin (`VMW_PSP_RR`) PSP.
`--iops` `-I`	Number of I/O operations to send along one path for this device before the PSP switches to the next path. You can use this option only when `--type` is set to `iops`.
`--type` `-t`	Type of round robin path switching to enable for this device. The following values for `type` are supported. `bytes`: Sets the trigger for path switching based on the number of bytes sent down a path. `default`: Sets the trigger for path switching back to default values. `iops`: Sets the trigger for path switching based on the number of I/O operations on a path. An equal sign (=) before the type or double quotes around the type are optional.
`--useANO` `-U`	If set to 1, the round robin PSP includes paths in the active, unoptimized state in the round robin set. If set to 0, the PSP uses active, unoptimized paths only if no active optimized paths are available. Otherwise, the PSP includes only active optimized paths in the round robin path set.