Re: (PM) Strange Activity on PM3

John W Baxter (jwblist@olympus.net)
Sun, 18 Apr 1999 10:03:12 -0700

At 8:38 -0700 4/16/99, Erick Baum wrote:
>If anyone out there has ever seen this before, I would really like to know
>what is going on. This has been going on for a couple weeks. It happens
>randomly between our 4 PM3's. The attached link is to our MRTG graph
>showing a HUGE spike in Ethernet ectivity coming from our PM3. This is
>actually one of the worst ones. It happens at any time of the day and
>ranges anywhere from a spike of 90k up to 250k of input and output for only
>a few minutes. This is happening locally on our ethernet becuase our T1
>MRTG graph does not show any spikes in transmission...
>
>http://freebsd.gvn.net/mrtg/pm4/pm4-day.gif
>
>Any ideas?

Do you have filters which block packets going *out* of the PM which are
addressed to IPs within the PM's pool?

If not:
User is working on a web site; hangs up his connection whilst the web
server is trying to send stuff. PM sees that packets are coming that it
doesn't know what to do with...it sends them back to your router, which
DOES know what to do with them: they belong to that PM, so back in they
come. Etc etc. Does wonders for ethernet traffic counts.

It can be--and has, extensively and exhaustingly, been--argued that the PM
shouldn't do that. [See the archives if you must.] Doesn't matter: it
DOES do that.

--John

--
John Baxter   jwblist@olympus.net      Port Ludlow, WA, USA
Give a man a fish and you feed him for a day.  Teach him to fish,
and you get rid of him for the weekend.
-
To unsubscribe, email 'majordomo@livingston.com' with
'unsubscribe portmaster-users' in the body of the message.
Searchable list archive: <URL:http://www.livingston.com/Tech/archive/>