100 full/half

[Scott Frye_1]

One of our HP-UX servers is has an ethernet card set on 100 half auto negotiate. We need to make it 100 full. The problem is SAM will not allow the change. I know there is a command I can run that will make the change (but will not stick if I reboot), but I forget what it is. Also, Isn't there a place I can make this change perminent, (like netconf?). Thirdly, do I need to stop and start the card after I make the change, if so how?

Thanks

Scott

[Pete Randall · Accepted solution]

Scott,

The command you seek is lanadmin. First run lanscan to obtain the card's instance number, then run "lanadmin -X 100FD 0" where 0 is the instance number. To make the change permanent, you need to update the appropriate config file in /etc/rc.config.d, which is based on the card's driver:

btlan hpbtlanconf
btlan0 hpeisabtconf
btlan1 hpbasetconf
btlan3 hpbase100conf
btlan4 hpgsc100conf
btlan5 hppci100conf
btlan6 hpsppci100conf


Pete

[Pete Randall]

And, oh, by the way, the port on the switch should be forced to 100FD as well. The 100BT cards don't auto-negotiate well.


Pete

[Scott Frye_1]

what about rebooting the card?

[Pete Randall]

Scott,

I'm not sure what you mean by "rebooting" the card. The lanadmin command will take effect immediately. Subsequent reboots of the machine will be handled by the changes in /etc/rc.config.d/_____lanconf.


Pete

[Scott Frye_1]

Thanks, you answered my question. There is no need to down the card.

Last question (I hope), how do I determine for sure my card can do 100 full?

[Pete Randall]

Scott,

Well, if the card is incapable of running 100FD, the lanadmin command will fail. That's your first clue. Running ioscan -kfnClan and posting the output so we can tell what kind of card it is would also help us figure it out, but the results of the lanadmin command will do.


Pete

[Scott Frye_1]

hppcolum # ioscan -kfnClan
Class I H/W Path Driver S/W State H/W Type Description
===================================================================
lan 0 0/0/0/0 btlan3 CLAIMED INTERFACE HP PCI 10/100Base-TX Core
/dev/diag/lan0 /dev/ether0

[Pete Randall]

Scott,

OK, it's a PCI card (rather than EISA) so it should be 100FD capable. There's no harm in trying it anyway.


Pete

[Scott Frye_1]

I appreciate all your input!!

[Scott Frye_1]

Last One!!
Can I expect any interrupt of network traffic? If the lanadmin command is successful? If the lanadmin command fails?

Thanks again for all your knowledge.

[Pete Randall]

Scott,

There may be a slight pause but no noticeable ill-effects.


Pete

[Scott Frye_1]

With this server hosting a web app, I shouldn't see any disconnect or service then?

[Pete Randall]

To be absolutely safe, since this sounds like a critical server, I would try to do this at during a slow period or even in a scheduled maintenance window if you can.


Pete

[rick jones]

The core 10/100 Interfaces - which are driven by btlan3 until 11.11 should autoneg pretty well - however, a common misconception is you can have one side auto and the other hardcoded to full and have it "autoneg" to full.

That just doesn't happen - the side that is hardcoded to either full or half duplex will not take part in autonegotiation (per the spec) and so the autoneg will fail. The side attempting to autoneg takes the failure to autoneg as meaning the device at the other end is an older legacy device capable of only half-duplex and so goes into half-duplex itself (again, per the spec).

So, I would only hardcode 100FD if you indeed have the switch port set to auto in addition to the NIC, and that is failing, and you are up on the latest patches for btlan3 _and_ the latest firmware on your switch. That is to say, I'd leave hardcoding as a last resort.

[Jeffrey Killian]

Our 10/100 cards (PCI) never negotiated well with the switch. We forced the NIC and then the switch port to 100M Full (using lanadmin and making the change permanent in the /etc/rc.config.d/hppci100conf by adding the line HP_PCI100_SPEED[card#]=100FD. That works well.