Configuring a CHPID on LPAR

6.10 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)

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.

Procedure

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