Subject: [netatalk-admins] Routing in the chain of the linux servers...
From: Konstantin Reznitsky (rkv@alpha1.gmslaw.com)
Date: Fri Jul 09 1999 - 10:39:28 EDT
I wrote this a while ago and sent it to umich support people, never got
anything back. It is written in their "BUG REPORT" style.
Environment:
Two Pentium (233/200MHz) machines running Red Hat-6.0 and
netatalk-1.4b2+asun2.0a18.2-oa1 (I tried your 1.4b2 without asun
with the same success) connected like this:
------ ------
WS1 eth1| |eth0 WS2 eth1| |eth0 WS3
--------------| L1 |---------------| L2 |-----------------
Zone1 | | Zone2 | | Zone3
net(range)1 |----| net(range)2 |----| net(range)3
L(1,2) are linux based routers.
WS(1,2,3) are test Macs with classic appletalk or open
transport (doesn't matter).
Description:
The problem is in when who can see whom, depending on which Zones
the routers belong to; file shares on L1 and L2 are seen by all
WSs in any configuration below. So are all the zones. "See" means
show in the chooser and can connect to the shared volumes."->"
means default zone for the router.
1. L1->Zone2 and L2->any zone(2or3) - all WS(1,2,3) can see each
other.
2. L1->Zone1 and L2->any zone(2or3) - WS2 can see WS1 and WS3,
WS1 can see WS2 and WS3, but WS3 can see only WS2 and NOT WS1.!!!
I have a strong feeling that this happens because the default zone
on the router L1 is configured on the second (eth1) interface,
unfortunetly I could not test the oposite because of the hardware
restrictions - different type of media (I do not have one more
hub). L1 machine has 3c905 and PCI NE2000 (Realtech), 3Com always
wants to be the first (eth0) and doesn't have a BNC connector.
I experimented with UAR (from CAP people) this effect never showed
up.
So, another thought, it might have something to do with appletalk
implementation in the kernel (UAR is not using it). Kernel 2.2.5 -
standard with RH-6.0. Tried RH-5.2 with 2.0.36 on the L1 with the
same effect.
Fix:
Assign the default zone on L1 to the network that connects it to
L2.
But here is another question. Is there a way to use this bug (or
whatever it is) to hide computers on one of the networks. It could
be very useful for example to connect this way admistration's and
students' networks. The question is how reliable this configuration would
be? This is another promlem, I was dealing with. Is there a way to
hide certain networks (zones) on the network intentionally? As far as I
know only certain hardware routers can do it. Is there any way to do it
with atalkd?
Thanks for any advice....
Konstantin.
This archive was generated by hypermail 2b28 : Sat Dec 18 1999 - 16:16:55 EST