networking is sometimes stopping

[peter demus]

hello !
there is strange problem using 2 servers. ping to each other is working fine (4096 bytes 100times). if i do telnet from PRODSRV to other server HP1, the prompt is delayed and while typing in the echo is delayed. running ping to the own server PRODSRV1 is dropping packets. some times ls -l -R is not finished in normal time via telnet.

if i start netstat -f inet i see there are many packets in the receive or send queue. after 15minutes or so mostly X-application on PRODSRV1 (waiting for data from HP1) will continue. however, after a short while, there are again packetes in the queues of the NIC stack.

HPUX 10.20 on D machines. 100MBit TwistedPair connection. there are no messages on the console on both machines showing strange network problems.

netstat -i shows no increase on I/O errors or dropped packets. yes they are in the queues....

what's wrong ? i had changed the NIC from 10MBit to 100MBit on the server HP1, a third server HP2 (with 100MBit from beginning) had the same behaviour now. why are the queues not being flushed ?

thanks a lot, peter demu

[Tom Geudens]

Hi,
mmm could it be that the speedsettings are not correct ?
Try the following
root/sv00138#lanadmin -x 0
Current Speed = 100 Full-Duplex Auto-Negotiation-OFF

If you don't get the 100FD ... that's probably where the problem is !

Regards,
Tom

[Duncan Edmonstone]

IIRC some of the 100BT cards on D class don't support 100Mb/s Full Duplex - could be your network port on your switch is set to auto-negotiate, and is getting it wrong - try setting both the NIC and the port on your switch to 100HD first and see if that sorts it out...

HTH

Duncan

[Rita C Workman]

I agree with checking your lan configuration...also remember to go into the file for that lan card and edit it there so it's safe on reboot.
See thread for details:
http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xbc3eec08252fd611abd50090277a778c,00.html

What you may also need to check is that your switch port is set the same...if you have your lan card going at 100 and switch at 10...ouch, same applies for auto neg=on at one end and off at the other. I always go with auto neg=off.

Hope this helps,
Rita

[Sukant Naik]

Hi Peter,

On top of what all the suggestions above, you can also check whether you are using NIS. There were issues when domainname is set and there is no NIS server for this domain.

I had given sudo privileges to end-users and some people out of curiosity had set the domainname coz of which the system is used to display the login prompt.

-Just my two cents.
Sukant

[Sridhar Bhaskarla]

Peter,

As pointed by others, it could be a speed problem.

The speeds should match if they are on the same hub/switch. If one is set to full duplex and the other to half, then the connections will be very slow though ping may respond well.

Make sure both the systems are set alike. It is fine if both the servers are running at half-duplex.

100 Full duplex with AUTO-off is the preferred speed if your switch and system support it.

-Sri

[Jim Turner]

Hi Peter,

If you using the A4308B in your D-Class, then I think you can only go 100Mb, HALF-duplex.

Cisco Catalyst switches with sufficiently up-to-date IOS will work just fine if you hard-set the duplex to half. The speed should still autonegotiate even though you've hard-set it to 100Mb on the HP-UX side.

YMMV, but here's the switch config steps for port 0/14 on a Cat 2924 (the one in my cube that hosts some C110's with the A4308B):
>en
Password:
#config term
Enter configuration commands, one per line. End with CNTL/Z.
(config)#int fast 0/14
(config-if)#speed auto
(config-if)#duplex half
(config-if)#end
#
%SYS-5-CONFIG_I: Configured from console by console
#copy running-config startup-config
Building configuration...
[OK]
#

BTW, I believe the file you need to look at on your D's is /etc/rc.config.d/hpeisabtconf. If your 100BT interface is lan1, here's how you'd need to config the file:
HP_EISABT_INTERFACE_NAME[0]=lan1
HP_EISABT_STATION_ADDRESS[0]=
HP_EISABT_SPEED[0]=100HD

Cheers,
Jim

[peter demus]

hi !

setting networking to 100 HD or 10 HD on the otther host was not a solution.

i changed the two interfaces lan1 and lan2 vice versa. the effect was that now there are no hanging X-window apps, however some apps indicates data missing from network 2.

it seems the internal NIC has problems. so i should use 2 of the extra plug-in NICs.

it has 2 extra 10 MBit HD cards (HP A2051, HP B3504).

thanks

[Printaporn_1]

Hi,

Check output from
#netfmt -t 50 -f /var/adm/nettl.LOG00

any IP conflict problem ?

[peter demus]

hi !

fast response......

i looked at netttladm. nothing. i should try Your command if i visit the custom.

there are no "strong" message on the console screen. only if i plug out the network cable.

!!
i tried also to switch from AUI to BNC to see if we have a AUI transciever problem. i used the other setting for the internal card jumper line. same problem via BNC connection.

!!
i notified that the LED was not blinking in the BNC mode. _why_ is the LED _flashing_ if i use the AUI connections ? it's written on the plate "flashing=problems". SQE test switch or heartbeat switch on AUI tranciever has no influence (normally off).
!!

the internal NIC has no LED.

thanks peter

[U.SivaKumar_2]

hi,
try giving a soft reset to the internal NIC
#lanadmin
Have you tried changing the twisted pair cable
also ?.

regards,
U.SivaKumar

[peter demus]

hello U. !

Yes, we have two identically machines (as spare part). so we changed machine, AUI transceiver, cables and switches.

as we changed servers (shutdown, off,on), the NIC was being reset a lot of times.

with this 2 machines we have same problems with the internal NIC. the server on the other side was not changed.

thanks peter

[U.SivaKumar_2]

hi,
what about using other two add-on NICs

regards,
U.SivaKumar

[peter demus]

Hi U. !

Yes that will be the next step. So we can avoid using the internal NIC.

However, why is the LED of the add-on 10BT NICs flashing ?

ciao peter

[U.SivaKumar_2]

hi,
have you connected that blinking add-on card to network ?.
is it AUI or BNC ?.
Have you properly terminated BNC cable with
50 ohm BNC terminator ?


regards,
U.SivaKumar

[Duncan Edmonstone]

Peter,

when you changed the speeds of your NICs to 100HD/10HD you did change the speeds of the ports on your hub/swicth too didn't you?

They need to match, and have auto-neg turned OFF.

HTH

Duncan

[peter demus]

hi !

the one machine PRODSRV is a D-class server with only 10MBit AUI-BNC NICs. 1 internal and 4 add-on.

with BNC mode LED is not blinking, it's working basically, well terminated, no error for base function.

with AUI mode, LED is blinking, no difference in function.

we use normally AUI there.

--> the hub/switch is alsways in 10MBit HD mode on that side

--> on the other side is HP1 and HP2 with 100MBit FD auto-neg-off connected to simple switch showing 100MBit FD

seems to be everything alright, but NIC tx,.rx queues have waiting packets while using the internal NIC.

ciao peter

[peter demus]

hi !

the machine PRODSRV is a E55 (with 4 extra 10Mbit NICs), the others HP1/2 is D380 (with 2 double-NICs 100MBit).

You think i have to add terminators on all unused cards and unused connectors ? i think no.

no connectors are used now on the unused cards.

thanks

[U.SivaKumar_2]

hi,
put terminator in each one of your unused cards.( no cable just terminate BNC ).
Now coming to the card which is blinking ,
Have you changed the AUI transceiver which
plug in to the add-on NIC ?.

regards,
U.SivaKumar

[U.SivaKumar_2]

hi,
Also i would like to know about the cable media
you are using with the AUI?.

regards,
U.SivaKumar

[peter demus]

Hi !

we haven't changed the AUI transceiver. we tried to find the error by changing to BNC.
it's the only one at this time.

it's AUI <--> RJ45 TP converter from ATI.

we have in the company a lot of old 63? ohm little green terminators useful for all the unused connectors.

bye, peter

[Mladen Despic]

Is it possible that you have duplicate ip-addresses on your network? If you disconnect the network cable from your system(s), can you still ping its ip-address from a remote host? If yes, then there is another host with the same ip-address.