ent vs et devices on aix

[exsnafu]

ok, so i've noticed some of my AIX servers have etX devices in my ifconfig -a output but I'm not sure what they are.

I go out and search, the AIX FAQ says that the etX devices are for frame types, enX being DIX for TCPIP and etX devices set up for 802.3 framing.

all my AIX servers are utilizing Network Interface Backup/etherchannel with two physical adapters making up the virtual. most of my servers have etX devices configured right alongside the enX and devices. some of them however, do not have any etX showing up.

as far as I can tell from lsattr etc, there is no difference in the way TCPIP/interfaces are configured on servers with etX vs without etX devices so how do the etX devices get there exactly? is there some option being set, is AIX determining this on its own?

at first I thought this had something to do with link aggregation on my etherchannel/NIB setup but its not consistent, I have some etherchanneled servers without etX

hopefully someone can shed some light here, thanks.

 

[MoreFeo]

enX and etX are sort of logical devices for physical entX device, each one for a different protocol.

http://www-03.ibm.com/systems/p/os/aix/whitepapers/pdf/tcpip_howto.pdf

Naming Conventions for Your Network Devices and Interfaces

When you install AIX, it automatically detects each adapter card and installs the
corresponding interface software. AIX uses the following naming convention for
network devices and interfaces:

Device Type Device Name Interface Name
Asynchronous Transfer Mode (ATM) atm# at#
Ethernet (IEEE 802.3) ent# et#
Ethernet (Standard, Version 2) ent# en#
Fiber Distributed Data Interface (FDDI) fddi# fi#
Loopback N/A lo#
Token-ring tok# tr#

In a LAN, the protocol used is Ethernet (Standard, Version 2) so you should use and configure enX instead of etX.

 

[exsnafu]

yup, I understand that part just fine but my question here comes(and maybe I'm just being thick headed) in how and why do I have the et# interfaces for some servers but not all. I do not see why these interfaces exist on a little over half my servers.

when you cfgmgr in a network interface does aix just create the et# interface right along with the en# and ent# and somewhere along the lines on some of the servers the et# were rmdev'd?

 

[p5wizard]

when you cfgmgr in a network interface does aix just create the et# interface right along with the en# and ent# and somewhere along the lines on some of the servers the et# were rmdev'd?

Exactly.



HTH,

p5wizard

 

[khalidaaa]

I can't think of other reasons than what you and p5wizard highlighted! Coz they always come together i pressume!

Regards,
Khalid

 

[MoreFeo]

One thing, you've said you see etX devices in ifconfig -a output.

If the etX devices aren't configured they shouldn't show in ifconfig, so I think some servers have etX configured with IP, and perhaps it shouldn't be.

 

[exsnafu]

they show up in ifconfig -a output but not as up or with an IP assigned... but initially I thought maybe they were some pseudo device used by the etherchannel because of that.