[HECnet] Node 4.249

[Paul_Koning at Dell.com]

BTW, the adjacency timeout rules in the routing spec are tuned for good quality physical links.   So Ethernet adjacencies allow two consecutive lost packets, but no more -- the timeout is 3x the hello interval.

I wonder if bridged connections should be more tolerant.   If both sides are regular DECnet implementations that isn't an option, but Rob's router could use a different multiplier to derive the broadcast listen timer value.   That would help if these bridged connections are prone to drop more packets but you can still reasonably expect no more than N in a row to be lost.   If so, the multiplier could be changed to N+1.

	paul

On Aug 28, 2012, at 3:30 PM, Rob Jarratt wrote:

The problem stopped around the time of your first email, so I guess you
fixed it. My user mode router is not reporting adjacency up and down any
more.

Regards

Rob

-----Original Message-----
From: owner-hecnet at Update.UU.SE [mailto:owner-hecnet at Update.UU.SE]
On Behalf Of Mark Wickens
Sent: 28 August 2012 17:08
To: hecnet at update.uu.se
Subject: Re: [HECnet] Node 4.249

I'm not totally clear on your setup. You have two interfaces, eth0 and
eth2.
I think I got that. And the bridge program is using eth0 for it's
bridge.
But how does your ethernet looks like? Is both eth0 and eth2 connected
to the same physical network? Is the router on that same segment as
well?

Both interfaces are on the same segment as the router.

What sessions are you seeing on the router?

On the router I see the following sessions:


----------------------------------------------------------------------------
---
      Private IP :Port #Pseudo Port                 Peer IP :Port   Ifno   Status

----------------------------------------------------------------------------
---
192.168.1.126   4711                 4711     130.238.19.25   4711         3   0
192.168.1.127   4711                 4711     130.238.19.25   4711         3   0

Where 192.168.1.126 is eth0 and 192.168.1.127 is eth2

And what did the routing table on the machine running the bridge look
like, if you have two interfaces?


No idea on this one.

The bridge program does not try to do anything clever with the UDP
packets, so they will be sent on any interface, based on your routing
table. It might sound as if your router/NAT was pointing at the IP
address of eth0, but the default entry of the routing table on your
machine would be using eth2. But this is all wild guessing right now...

OK, that probably explains it. I thought the bridge was tied to that
particular
interface. It's worth pointing out that what I'm doing it probably daft -
the
2nd card was installed to use for a SIMH instance, so I should probably
de-
configure it from an OS point of view.