Configuring a CHPID on LPAR

Red Hat Enterprise Linux 8.6 LPAR mode

For Linux® in LPAR mode, directories that represent CHPIDs contain a configure attribute that you can use to query and change the configuration state of I/O channel-paths.

About this task

The following configuration changes are supported:

From standby to configured (configure)
From configured to standby (deconfigure)

Procedure

To configure a CHPID, set its configure attribute by writing the value 1 to it. To deconfigure a CHPID, set its configure attribute by writing 0 to it.

Issue a command of this form:

# echo <value> > /sys/devices/css0/chp0.<CHPID>/configure

where:

<CHPID>: is a two digit hexadecimal CHPID.
<value>: is either 1 or 0.

You can also use the lschp and the chchp commands to query and set the configure value.

Examples

To set a channel path with the ID 0x40 to standby issue:
```
# echo 0 > /sys/devices/css0/chp0.40/configure
```
This operation is equivalent to performing a Configure Channel Path Off operation on the hardware management console.
To read the configure attribute to confirm that the channel path has been set to standby issue:
```
# cat /sys/devices/css0/chp0.40/configure
0
```
To set the same CHPID to configured issue:
```
# echo 1 > /sys/devices/css0/chp0.40/configure
```
This operation is equivalent to performing a Configure Channel Path On operation on the hardware management console.
To read the status attribute to confirm that the CHPID has been set to configured issue:
```
# cat /sys/devices/css0/chp0.40/configure
1
```