What is the use of new ethernet device driver attribute "autoconfig" in AIX 7.3 ?

What is the use of new ethernet device driver attribute "autoconfig" in AIX 7.3
Question & Answer


Question

What is the use of new ethernet device driver attribute "autoconfig" in AIX 7.3?

Answer
The new attribute autoconfig is available for ethernet device driver starting AIX 7.3. This attribute allows users to choose which ethernet port to bring to available state, and which to bring in defined state. This attribute is useful for avoiding problems that may occur when an unused ethernet port is opened or queried by various system components and monitoring tools.


It is not available in pre AIX 7.3 level and older device drivers.


The autoconfig has two allowed values.
(1) available (default)
(2) defined


When the AIX network device configuration method runs, it queries the autoconfig value for the device driver. If it is exists and had the value of "available" or if the device driver does not have autoconfig attribute, the device configuration method attempts to bring the ethernet port to the "available" state.


If the autoconfig attribute exists and is set to "defined", the AIX device configuration method does not attempt to bring the ethernet port to make "available" and leave it in "defined" state.


This attribute is available in only following device drivers.
(1) musentdd
(2) shientdd
(3) lnc2entdd
(4) mlxcentdd
(5) vnicdd


To find name of device driver used by the ethernet port, run following lsdev command.
# lsdev -F "name ddins" | grep <entX>


For example, lsdev output shows that lnc2entdd driver is used by ethernet port ent14.
# lsdev -F "name ddins" | grep ent14
ent14?????? pci/lnc2entdd


If autoconfig is available for the ethernet port then lsattr will list it.
# lsattr -El ent14
alt_addr????????????? 0x000000000000???? Alternate Ethernet address???????????????????? True
autoconfig??????????? defined ? ?? ????? Configuration state??????????????????????????? True
bar0?????????? ? ? ?? 0x3d017c2400000??? Bus memory address 0?????????????????????????? False
busintr?????????????? 5128?????????? ? ? Bus interrupt level???????????????????????? ?? False
chksum_offload??????? yes??????????????? Request checksum offload?????????????????? ? ? True
cksum_ip?????? ? ? ?? yes??????????????? Request IP checksum offload??? ? ? ??????????? True
...
...


To change value of autoconfig to defined, run following chdev command.


# chdev -l <entX> -a autoconfig=defined


When autoconfig is set to defined, "lsdev -Cc adapter" will list the adapter in defined state. When ethernet port is ready for the use, change the value to available and run cfgmgr.?