topic Re: Considerable traffic on Loopback - why? in Operating System - HP-UX

Considerable traffic on Loopback - why?

KURT HARLESS — Wed, 21 Jun 2000 16:36:34 GMT

Noticing in glace significant traffic on my lo0 loopback interface and am wondering why? This is only happening on one of my two HP servers... How do I diagnose the cause?

Re: Considerable traffic on Loopback - why?

Berlene Herren — Wed, 21 Jun 2000 17:47:31 GMT

Do you have the latest ARPA patch on this server?

You could download TCPDump from
http://hpux.cs.utah.edu/hppd/hpux/Networking/Admin/tcpdump-3.4/ and run that. That might tell you.

Berlene

Re: Considerable traffic on Loopback - why?

KURT HARLESS — Wed, 21 Jun 2000 18:00:14 GMT

ARPA?

Re: Considerable traffic on Loopback - why?

Berlene Herren — Wed, 21 Jun 2000 18:14:49 GMT

ARPA Cumulative Patch:

PHNE_20834 S800 10.20
PHNE_19927 S700 10.20
PHNE_21767 11.0

I would check the differences in patch levels between the two, first.

Berlene

Re: Considerable traffic on Loopback - why?

Albert E. Whale, CISSP — Wed, 21 Jun 2000 18:19:52 GMT

Kurt,

While TCP Dump is an effective Networking Tool, I doubt that it will locate the traffic on the lo0 interface (it's a local interface, and never gets to the network).

I am in need of some points to make it to the level. Perhaps we can help each other out?

I'll gladly dig further.

Re: Considerable traffic on Loopback - why?

Albert E. Whale, CISSP — Wed, 21 Jun 2000 18:23:08 GMT

Btw, The ARPA Patch is an excellent suggestion.

Re: Considerable traffic on Loopback - why?

Albert E. Whale, CISSP — Wed, 21 Jun 2000 18:48:39 GMT

Kurt,

Have you tried examining the output oif netstat?

Try the following:

netstat -a | grep localhost

This will tell you about all of the connections which are being used in the Server and which Sockets they are utilizing.

Also, does your inpackets equal your out packets?

Try the following:

[/] # netstat -I lo0
Name Mtu Network Address Ipkts Opkts
lo0 4136 127.0.0.0 localhost 79606 79606

Be sure that the # in = # out.

Re: Considerable traffic on Loopback - why?

Antonio Valle_1 — Wed, 21 Jun 2000 18:57:53 GMT

Are you using Oracle?

:-) It is very usual that some application use the loopback address to communicate with themself. I mean that if you use some kind of client-server app and both the client and the server are installed on the same system, then you will have a lot of loopback traffic.

Antonio

Re: Considerable traffic on Loopback - why?

KURT HARLESS — Thu, 22 Jun 2000 15:55:56 GMT

Interesting.... I am running Oracle Apps on this server, db and oracle reports. So is the result of bequeath operations in NET8?

Re: Considerable traffic on Loopback - why?

Antonio Valle_1 — Thu, 22 Jun 2000 16:01:00 GMT

I think so.