ifconfig en0 down
ifconfig en0 detach
or the last line in smit menus says apply to database only....if you answer yes
it will take changes and the next reboot will do it.
===============
Make sure the cards are talking the same speed,the same full or
half duplex, if one is not matching, it will not communicate. Both ends,
router and card, or card and card...or hub and card.
On New ethernet cards, especially on PCI machines 7025-F50/PCI
Ethernet Performance Tuning. The performance of the PCI Ethernet
Adapter (Features 2985 and 2987), when used in the 7025-F50, can be
significantly improved by setting the tx_que_size and rx_que_size
parameters to 256. This can be accomplished by using the following
command to change the adapter settings:
smitty chgenet
Set the "HARDWARE TRANSMIT" queue size and "HARDWARE
RECEIVE" queue size fields to 256.
smit chinet
to change the full duplex and the media speed Change/Show
Characteristic of Network Interface (chinet, shinet)
Duplex
The Ethernet High-Performance LAN Adapter (8f95) can be configured
to operate in a full duplex 10BASET network. This mode of operation is
only valid using the adapter's RJ-45 (10BASET) port. Duplex mode is
not valid when using the AUI port or the BNC (10BASE2) port.
Beginning with AIX Version 4.1.5, the 10/100 Mbps Ethernet TX MCA
device driver (8f62) supports the following additional configuration
parameters:
Media Speed
The 10/100 Mbps Ethernet TX MCA device driver (8f62) supports a
user-configurable media speed for the adapter. The media speed
attribute indicates the speed at which the adapter will attempt to
operate. The available speeds are: 10 Mbps half-duplex, 10 Mbps
full-duplex, 100 Mbps half-duplex, 100 Mbps full-duplex, and
auto-negotiation. The default is auto-negotiation. Note:Auto negotiate
does not function properly, it is better to select either 100 or 10 but not
auto.
Check with
netstat -v | egrep "STATISTICS|Media Speed"
lsattr -E -l en0
entstat -d ent0