Slow Network Connection Drops offline

[Anand Chauhan]

I am using HP 9000 running HP-UX 11.11, the machine has two network cards, I am not using the onboard card, but the add on card with interface lan0. It is in the university computer science subnet, and all the machines in that subnet work fine.

PROBLEM IS : This particular HP machine goes offline while FTPing large files, and when I pull out the cable from the network card and put it back on, is becomes online, again. Can somebody suggest what might be the problem? Please let me konw if you need extra info.

-Andy Chauhan

[Darrell Allen]

Hi Andy,

The first thing I check for problems with file transfer (slow, dropping, etc) is for a duplex mis-match between your server and the switch. This happens often on 100Mb links using auto-negiotiation.

Verify the speed/duplex setting on your server and the switch. Use "lanscan" to determine your cards and PPA number. Then use "lanadmin -x PPA#" to see the current setting and "lanadmin -X PPA# speed" to change it if needed.

I always force my server network cards and the switch to the desired speed and duplex setting simply because autoneg often fails.

If the server and switch don't match, I'd force the switch to the desired setting first.

Search the forums for duplex and you'll find a bunch of threads on this.

Darrell

[harry d brown jr]

Interesting!

When it goes offline, do you mean that it doesn't respond to pings from another server??

Are there any errors in syslog??

Can you ping another host from the console when it "goes offline"??

The next time it "doesn't respond", can you check to see if inetd is running??

What does "model" return??

Post the output from lanadmin (select lan, then display, then q to quit)

Of course the router could be suspect, the cable, and the lan card.

live free or die
harry

[Darrell Allen]

In case it is a duplex mis-match, here's a current thread that could help:
http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xabcca848deccd61190050090279cd0f9,00.html

Darrell