Changing network card from half duplex to full duplex!!

[Amit Manna_6]

HI
I want to change the network card settings from half duplex to full duplex.

Please find the network interfaces and the package status attached in the file.


Can anybody tell me what are the steps to be followed to make the changes:

Can we carry out the changes in the production setup running or we need to do it in backup window.

Please let me know

[Rick Garland]

Use 'lanadmin -X PPA# '
lanadmin -X 0 100FD


This is an example - modify for your environment.

When doing the command you will lose connectivity for some 15 sec. so you will probably want to research how your SG is setup. Example, is this your heartbeat?

Other side of equation is how is the port on the switch configured? If it is set for half duplex then you need to change there as well.

[Borislav Perkov]

Hi,
You can use
lanadmin
command. But you have to see before on what is this card connected, hub or switch. Because the device where it is connected gives the operation mode of the card, hub can somethimes make the connection to be half duplex.
Regards

[Fabio Ettore]

Hi Amit,

command to change lan speed is the following:

lanscan
(to obtain CrdId# of lan cards)

lanadmin -X 100FD
(to change speed)

Anyway it depends on hardware, not all lan cards support full duplex.

I don't see problems to change them in SG environment.

Hope this helps.

Best regards,
Fabio

[V. Nyga]

Hi,

you also can change it in SAM - Networking and Communication - Network Interface cards
'Action - modify'.

Here you can see if FullDuplex is supported, also you have to disable autoneg.

Volkmar

[Philippe Vervoort]

Hello,

To make this change permanent, set HP_BTLAN_SPEED[0] to 100FD in the file /etc/rc.config.d/hpbtlanconf
( unless you use SAM, in which case you should turn Autoneg to OFF )

Greetings,
Philippe

[Basheer_2]

Attached PDF explains all the info.

[D Block 2]

Also, verify on the switch end (could be a ProCurve), the port characteristics, Half/Full.

[D Block 2]

Also, verify on the switch end (could be a ProCurve), the port characteristics, Half/Full.
can also be changed.

You can also use Glance, drill down to Network and then 'S'elect the lan interface and look for Errors.

my 2-cents

[Mel Burslan]

although sam does a fine job doing this for you, I strongly discourage you from using sam as it puts in the hardware address (a.k.a. MAC address) of the card into the lan configuration file and should there be a need to change this card, you may have some problems if you don't know what you are doing.

manual method:

# ioscan -fknC lan

you will see something like :

lan 1 0/3/1/0/6/0 igelan CLAIMED INTERFACE HP A9784-60001 PCI/PCI-X 1000Base-T FC/GigE Combo Adapter

-or-

lan 2 10/8/1/0 btlan4 CLAIMED INTERFACE PCI Ethernet (10110009)


the important field on these outputs are the 4th field:

igelan or btlan4. There are corresponding configuration files for each of these drivers under /etc/rc.config.d directory, starting with letters "hp". Find the file for your specific type of adapter and modify it on the line which reflects the speed and duplex.

example here is for igelan driver:

# vi /etc/rc.config.d/hpigelanconf

modify these two lines

HP_IGELAN_INTERFACE_NAME[0]=lanX
HP_IGELAN_SPEED[0]=100FD

where lanX is your lan interface name

save this file

# /sbin/init.d/hpigelan stop
# /sbin/init.d/hpigelan start

this will permanently nail down your speed and duplex settings to 100 Full Duplex.

Make sure you are not trying to nail a gigabit interface to 1000FD because it is not supported.

Also, as many people before me warned you, make sure your network people nail down the port speed what you are setting your port to. Otherwise you will see a lot of slow communications and errors logged against this interface.

HTH

[rick jones]

Unless you have actuall errors, I would suggest that you stick with autoneg everywhere. And if in this day and age there are switches that don't autoneg correctly, you might consider either a firmware upgrade, or replacing the switch.

How Autoneg is supposed to work:

When both sides of the link are set to autoneg, they will "negotiate"
the duplex setting and select full duplex if both sides can do
full-duplex.

If one side is hardcoded and not using autoneg, the autoneg process
will "fail" and the side trying to autoneg is required by spec to use
half-duplex mode.

If one side is using half-duplex, and the other is using full-duplex,
sorrow and woe is the usual result.

So, the following table shows what will happen given various settings
on each side:

Auto Half Full

Auto Happiness Lucky Sorrow

Half Lucky Happiness Sorrow

Full Sorrow Sorrow Happiness

Happiness means that there is a good shot of everything going well.
Lucky means that things will likely go well, but not because you did
anything correctly :) Sorrow means that there _will_ be a duplex
mis-match.

When there is a duplex mismatch, on the side running half-duplex you
will see various errors and probably a number of late collisions. On
the side running full-duplex you will see things like FCS errors.
Note that those errors are not necessarily conclusive, they are simply
indicators.

You can see link-level stats with lanadmin -g mibstats

[Mel Burslan]

with all due respect to Rick, if we let the gbit interfaces to autonegotiate connected to 100mbit network switches from cisco (quite new models with pretty much uptodate f/w revisions), we sadly see them negotiate 100HD. which is not good. So, every time I install a new server, I make sure network people nail their side down to 100FD and I do the same.

So, this day in age, somethings are still not working as expected. Just an observation.

[rick jones]

If the Ciscos are set to autoneg, and failing autoneg, then clearly you need different switches :)

It was unpleasant to bad before when folks weren't consistent about hardcoding all switch ports and NIC to the same values - moving cables around would wreak havoc. Also, since system defaults are autoneg, forgetting to alter that during an install... well...

And today, with more and more of the NICs being 10/100/1000 instead of just 10/100, the business of hardcoding will start to bite people when they switch-out their 100BT switches and put-in GbE switches and wonder what went wrong.

Perhaps my life has been charmed, perhaps I've had good cable lengths, or perhaps it has been my use, predominantly, of ProCurve switches :) I'll confess that I've not used many Cisco switches.