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items: Multiple interfaces eth0, eth1 on different subnets
items: Re: Multiple interfaces eth0, eth1 on different subnets

Multiple interfaces eth0, eth1 on different subnets
type: item
description: Hello there. I am trying to put my OpenVZ machine on multiple networks so I can create a VPS on any of the VLAN's here. I am running into two problems: 1) When I start a VPS, it always does the arpsend on eth0. This isn't fatal, just a warning 2) The fatal error: VPS on the eth1 interface are unable to route anywhere - they can only connect to the local network. I am assuming that this is because the default route on the machine is on eth0. Is there any way to set a default route inside of the VPS that is different from the default route outside? Thanks, Mark
creator: pyite
date: 2007-02-01T19:05:44-00:00

Re: Multiple interfaces eth0, eth1 on different subnets
type: item
description: Hi, it's my problem, too... It seems, that the person on [message #7394] "Dual NIC environment" had the same problem, but the other reader didn't understand his explainations and thougt he played a joke with them... As i found in the searches, the main problem seems the problem with the wrong interface / and even now the wrong interface used by arpsend ... even it's "only" a warning... My config: VHost: eth0: a.b.c.d/255.255.255.224 eth1: 10.0.0.1/255.255.255.0 VE (with standard openvz rules): veneth0: 127.0.0.1 veneth0:0: a.b.c.e veneth0:1: 10.0.0.222 1) from VHost AND other server outside: ping a.b.c.e => works ping 10.0.0.222 => works 2) from VE to VHost: ping a.b.c.d => works ping 10.0.0.1 => works 3) from VE to other server outside: ping a.b.c.g => works ping www.heise.de, www.t-online.de and so on => works ping 10.0.0.3 => did'nt work but ping -I 10.0.0.222 10.0.0.3 => work I've used tcdump -I veneth0 on VHost to verify the packet transfer => so the source routing for 10.0.0.222 is'nt right... I thought "no problem", I found here the tipp to change debian-add_ip.sh ... so i change the script to add routes behind veneth0:0 up route add -net a.b.c.a netmask 255.255.255.224 dev veneth0:0 and veneth0:1 up route add -net 10.0.0.0 netmask 255.255.255.0 dev veneth0:1 now all pings and my webinterface connection to the mysql server on 10.0.0.3 works correctly ... BUT the dns server could'nt be queried (( I tried to change the default route from the VE FAKEGATEWAY to my Gateway: up route del default gw 191.255.255.1 up route add default dev venet0:0 but it didnt help either. If I remove theses routes, dns works / use of 10.0.0.222 is wrong again... ==> Is it possible to change the arpsend command and when yes, where? I grepped the /etc/vz/ files for arpsend, but didn't find it... Or is there an easier way to get the right routing? Thanks. Reiner
creator: Reiner030
date: 2007-02-14T14:46:22-00:00

Re: Multiple interfaces eth0, eth1 on different subnets
type: item
description: Please, take a look at this article https://wiki.openvz.org/Source_based_routing I hope it will help to solve your problems with routing.
creator: Andrey Mirkin
date: 2007-02-15T14:56:44-00:00