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items: 1 VPS IP, Multiple Host Interfaces
items: Re: 1 VPS IP, Multiple Host Interfaces

1 VPS IP, Multiple Host Interfaces
type: item
description: I have tried just about every ip route combination I can think of to make this work. I have a host with 3 interfaces: 2 separate public interfaces on different networks; with both networks' gateways able to route to each other. 1 private network (192.168.100.0/24). The VPS in question has an IP address on only 1 of the two hosts' public networks. The default gateway for either network should work, but for some reason, the VPS cannot send data to the public network that it doesn't have an IP address for. If I ifdown the interface on network in question on the host, the VPS can immediately send packets to the network in question. The weird thing is, it magically starts working at some point in the day, but stops by the time I get to work in the morning. This happens if the routing table is left at the defaults when the VPS is created. **A couple more stats: iptables is off on the host and VE the VE is being given a real routable IP address (no private). -Eric
creator: cberic3
date: 2007-04-27T13:03:30-00:00

Re: 1 VPS IP, Multiple Host Interfaces
type: item
description: Hello, can you post the output of ip a l ip r l commanfs in VE _and_ on HN. Thanks, Vasily.
creator: Vasily Tarasov
date: 2007-04-28T07:24:47-00:00

Re: 1 VPS IP, Multiple Host Interfaces
type: item
description: INSIDE VE= root@wiki:/root>ip a l 1: lo: <LOOPBACK,UP> mtu 16436 qdisc noqueue link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 brd 127.255.255.255 scope host lo 3: venet0: <BROADCAST,POINTOPOINT,NOARP,UP> mtu 1500 qdisc noqueue link/void inet 127.0.0.1/32 scope host venet0 inet 198.175.18.60/32 brd 198.175.18.60 scope global venet0:0 root@wiki:/root>ip r l 192.0.2.0/24 dev venet0 scope host 169.254.0.0/16 dev venet0 scope link default via 192.0.2.1 dev venet0 src 198.175.18.60 root@wiki:/root> ON HW NODE= root@openvz1:/root>ip a l 2: lo: <LOOPBACK,UP> mtu 16436 qdisc noqueue link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 brd 127.255.255.255 scope host lo 4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:0b:cd:4f:5c:15 brd ff:ff:ff:ff:ff:ff inet 198.175.18.64/24 brd 198.175.18.255 scope global eth0 6: eth1: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:0b:cd:4f:5d:4a brd ff:ff:ff:ff:ff:ff inet 198.175.28.56/26 brd 198.175.28.255 scope global eth1 8: eth2: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000 link/ether 00:0f:b5:46:9f:f3 brd ff:ff:ff:ff:ff:ff inet 192.168.100.64/24 brd 192.168.100.255 scope global eth2 1: venet0: <BROADCAST,POINTOPOINT,NOARP,UP> mtu 1500 qdisc noqueue link/void root@openvz1:/root>ip r l 198.175.18.60 dev venet0 scope link 198.175.28.0/26 dev eth1 proto kernel scope link src 198.175.28.56 192.168.100.0/24 dev eth2 proto kernel scope link src 192.168.100.64 198.175.18.0/24 dev eth0 proto kernel scope link src 198.175.18.64 169.254.0.0/16 dev eth1 scope link default via 198.175.18.1 dev eth0 root@openvz1:/root>
creator: cberic3
date: 2007-04-28T14:36:15-00:00

Re: 1 VPS IP, Multiple Host Interfaces
type: item
description: Any thoughts..? I can't tell why it is intermittent. If I ifdown and ifup the 198.175.28.0 interface on the host, the VE works for a while sending traffic to that network, but will stop working in less than 24 hours (I haven't tried to pin exactly when it happens). -Eric
creator: cberic3
date: 2007-05-01T14:23:59-00:00

Re: 1 VPS IP, Multiple Host Interfaces
type: item
description: Hmm... Can you give an access to the node in question? Vasily
creator: Vasily Tarasov
date: 2007-05-02T08:16:48-00:00

Re: 1 VPS IP, Multiple Host Interfaces
type: item
description: One more question, can you be more precise, which nodes you can reach and which you can't: post here precise commands: ping <ip> ping <ip> ... Thanks, Vasily.
creator: Vasily Tarasov
date: 2007-05-02T08:23:38-00:00

Re: 1 VPS IP, Multiple Host Interfaces
type: item
description: ping everything on our networks (198.175.16.0/20) except 198.175.28.0/26 . 198.175.28.0/26 is the network that the host has an interface for / IP address on (198.175.28.56), but the VPS doesn't have an IP for. Its almost as if, because the host has an interface on that network and I don't give the VPS an IP on that network, it won't route packets to that network; even though the public address the VPS does have is a public network that routes to the needed subnet. It works for some time after I ifdown and ifup the 198.175.28.0/26 interface on the host, but sometime within 24 hours it stops working. -Eric
creator: cberic3
date: 2007-05-02T12:16:15-00:00

Re: 1 VPS IP, Multiple Host Interfaces
type: item
description: Well I can only advise you to try to use tcpdump to investigate the problem...
creator: Vasily Tarasov
date: 2007-05-02T12:40:40-00:00