Thanks a lot, Grant! I don't understand problem (1). Do you mean the routing between the two subnets connected by the gateway? I think the gateway can route correctly since I have "16.119.144.64 16.119.144.35 255.255.255.224 UG 0 0 0 eth1" in Node1's routing table, and a similar entry in Node2's routing table. Problem (2) seems to be caused by "16.119.144.66 0.0.0.0 255.255.255.255 UH 0 0 0 teql0" in Node1's routing table. There are two paths to 16.119.144.66, one with direct connection, and one with the gateway. I don't know how to specify both cases at the same time. As I said in my original post, It seems that the problem is that when packets are forwarded by the teql0 interface to each local Ethernet cards, the routing is still based on the routing entry for the teql0_IP address in the routing table, instead of being based on the IP of the local Ethernet interface that packets are passed to. Since I can't both specify the gateway address and not specify at the same time, there is only one link that teql finds working and pass packets to at each time. But it sounds unreasonable for TEQL to be implemented that way. Probably my configuration is wrong somewhere. I think your idea of dummy interfaces will probably work, but I'll try to change the gateway into a bridge first. Not sure which one is simpler yet. Thanks a lot again! -Ji -----Original Message----- From: lartc-bounces@xxxxxxxxxxxxxxx [mailto:lartc-bounces@xxxxxxxxxxxxxxx] On Behalf Of Taylor, Grant Sent: Thursday, June 23, 2005 5:03 PM To: lartc@xxxxxxxxxxxxxxx Subject: Re: urgent TEQL problem Based on your previous email and this email I see a couple problems with your situation. 1) Your ""Gateway will not be able to ""route correctly between two interfaces on the same subnet. 2) Node1 is ARPing out eth1 to try to find 16.119.114.66 on it's local subnet as it should be there but it is not as it is on the other side of a gateway. If you do not want to do this on layer 2 and turn your gateway in to a bridge I think you will have to do all of this on layer 3 and route *BOTH* sides of teql0, how to do this I'm not sure of at the moment. I have a feeling you will need to ultimately try to reach an IP that is not on any of your physical network cards but rather something on a dummy interface that is accessible via a route using either interface to get to. I'll try to describe such a setup below. Node 1: - eth0: <subnet 1>.1 - eth1: <subnet 2>.1 - teql0: <subnet ?>.1 - dumy0: <subnet 3>.1 Node 2: - eth0: <subnet 1>.2 - eth1: <subnet 4>.2 - teql0: <subnet ?>.2 - dump0: <subnet 5>.2 Gateway: - eth0: <subnet 2>.254 - eth1: <subnet 4>.254 (Sitting her looking at this I'm not entirely sure that you even need teql0 but rather ECMP routing.) Node 1 routing table: <subnet 3> via <subnet 1>.2 metric 2 <subnet 3> via <subnet 2>.254 metric 1 Node 2 routing table: <subnet 5> via <subnet 1>.1 metric 2 <subnet 5> via <subnet 4>.254 metric 1 Gateway routing table: <subnet 3> via <subnet 2>.1 metric 1 <subnet 5> via <subnet 4>.2 metric 1 This *SHOULD* (if I have things correct in my head) establish two routes from <subnet 3> to <subnet 5> with the same overall metric of 2. However to use ECMP you will need the metrics for both routes from <subnet 3 or 5> to <subnet 5 or 3> to be the same on Node 1 and Node 2. Thus I might modify the routing tables as such. Node 1 routing table: <subnet 3> via <subnet 1>.2 metric 2 <subnet 3> via <subnet 2>.254 metric 2 Node 2 routing table: <subnet 5> via <subnet 1>.1 metric 2 <subnet 5> via <subnet 4>.254 metric 2 Gateway routing table: <subnet 3> via <subnet 2>.1 metric 0 <subnet 5> via <subnet 4>.2 metric 0 As my pager goes off I realize that I have to submit a partial post back to the list, but hopefully there is enough here to get a couple of points across and enough for someone else to work with to help flesh out this idea. Grant. . . . Li, Ji wrote: > One more thing to add is that when I "ping 16.119.144.66" from Node1 > (16.119.144.66 is the teql0 of Node2), all messages I saw from > Node1.eth1 are ARP messages "Who has 16.119.144.66? Tell 16.119.144.33". > > Thanks, > -Ji _______________________________________________ LARTC mailing list LARTC@xxxxxxxxxxxxxxx http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc _______________________________________________ LARTC mailing list LARTC@xxxxxxxxxxxxxxx http://mailman.ds9a.nl/cgi-bin/mailman/listinfo/lartc
