Ascend Archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: (ASCEND) Syslog brings up the WAN link (Pipeline)



> I can't leave syslog running long enough to explore any delays because 
> any time it's running the WAN link stays up for good. The link stays up
> until it times out and as soon as syslogd logs the disconnect it brings 
> the link back up again.

Are you syslogging to a machine across the WAN from the Pipeline?
That will bring the link up.  It's supposed to, how else would it
communicate with the far end.  I suppose you could construct a Call 
filter to prevent syslog (port 514) from bringing up the link, but
then you'd miss some syslogged messages. 

If you're syslogging to a machine on the same end of the WAN as the
pipeline, then it should not bring up the link.  Mine doesn't.  I
believe the Pipeline has the smarts to realize that both the sender
(pipeline) and receiver (syslog server) MAC addresses are both on the
ethernet side, so it ignores them.

>  James Johnson sent me this explanation...
> 
> >BTW if you're running TCP/IP you're running ARP. ARP - address resolution
> >protocol, attempts to associate a hardware address, e.g. ethernet MAC
> >address, to an IP address. This is used for locating machines on your
> >network. If the ARP request fails to find an IP<=>MAC relationship on the
> >local net then the packet get forwarded to the default gateway. In this
> >case it is probably your Pipeline. And this is how/why you get the dial out...

ARP entries don't have to be queried each time a packet is sent.  ARP
entries are cached for varying lengths of time, depending on the IP
implementation.  I've had problems with ARP bringing up the link, some
of them pretty puzzling.  I've wrung my hands of it all and just
hard-coded ARP entries for my home PC, home unix machine, Pipleline,
the Max at work, the nameservers, the router port for that subnet.
I've hard-coded these ARP entries into the Unix machine and the
pipeline's bridge table.  The PC isn't on enough to be a problem.  I
don't know if you can hard-code ARP entries in Win95.

The only strangeness I have now is that if I ever reset the Pipeline,
it doesn't talk to the machines at home and doesn't bring up the link
to work unless I force it to on the console.  The ARP entries are in
the bridge table, but it won;t talk to them.  I haven't spent much
time trying to figure this out since I never reset the pipeline.  My
workaround is to delete the entries from the bridge table when the
pipe comes up, and then to a tftp restore config from my unix machine
to out them back (quicker than typing it all in).  

BTW, I run bridging rather than routing on my setup.

-- 
Earl Barfield  --  Operations Department / Information Technology  
Georgia Institute of Technology, Atlanta Georgia, 30332
Internet: Earl.Barfield@oit.gatech.edu    earl@prism.gatech.edu
          earl@fantasy.gatech.edu         earl@oit.gatech.edu
++ Ascend Users Mailing List ++
To unsubscribe:	send unsubscribe to ascend-users-request@bungi.com
To get FAQ'd:	<http://www.nealis.net/ascend/faq>