Reinhard Brandstädter
2007-Jul-17 10:33 UTC
[Xen-users] VLANs and Networking between DomU and Dom0
Hello, I''ve configured multiple bridges on my Dom0 for VLAN tagged and untagged traffic. On the Dom0 I have two physical interfaces and one VLAN interface: eth0 (untagged) eth1 (untagged) (network config 192.168.3.10/24) eth1.1002 (VLAN 1002) (network config 192.168.3.104/24) Xen creates three bridges in the networking script: dir=$(dirname "$0") "$dir/network-bridge" "$@" vifnum=0 netdev=eth0 bridge=xenbr0 "$dir/network-bridge" "$@" vifnum=1 netdev=eth1 bridge=xenbr1 "$dir/network-bridge" "$@" vifnum=2 netdev=eth1.1002 bridge=xenbr1V2 resulting in the bridges: xenbr0 xenbr1 xenbr1V2 Now I can create two virtual machines that use the ''xenbr1V2'' as network device (network config 192.168.3.0/24, assigned IP .101 and .103) and those machines can see (and communicate/ping) with eachother. Another virtual machine uses ''xenbr1'' as network device (network config 192.168.3.0/24, assigned IP .102). As expected it is not possible to ping between the machines on the VLAN bridge and the one on the untagged bridge. However I can''t ping the Dom0 from the VLAN tagged machines but I can from the untagged machines (and vice versa). I assumed that this might have something to do with routing (since i use the same network/mask on both nets (tagged and untagged). So I checked with the routing table. with this table i can ping the untagged VM: Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface xxx.xx.x.x 0.0.0.0 255.255.255.0 U 0 0 0 eth0 192.168.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 0.0.0.0 xxx.xx.x.x 0.0.0.0 UG 0 0 0 eth0 With this table I expected to be able to ping the tagged VM but couldn''t: Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface xxx.xx.x.x 0.0.0.0 255.255.255.0 U 0 0 0 eth0 192.168.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1.1002 0.0.0.0 xxx.xx.x.x 0.0.0.0 UG 0 0 0 eth0 This might not even be a Xen specific issue but maybe anyone here has/had a similar configuration and might point me in the right direction. Thanks, Reinhard _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Reinhard Brandstädter
2007-Jul-17 11:57 UTC
Re: [Xen-users] VLANs and Networking between DomU and Dom0
Could it be that I have to attach another virtual interface (vif) to the ''xenbr1V2'' bridge in Dom0? That what''s usually configured in den DomU Script but for Dom0? Is theis doable? Reinhard On Tuesday 17 July 2007 12:33:33 Reinhard Brandstädter wrote:> Hello, > > I''ve configured multiple bridges on my Dom0 for VLAN tagged and untagged > traffic. On the Dom0 I have two physical interfaces and one VLAN interface: > eth0 (untagged) > eth1 (untagged) (network config 192.168.3.10/24) > eth1.1002 (VLAN 1002) (network config 192.168.3.104/24) > > Xen creates three bridges in the networking script: > dir=$(dirname "$0") > "$dir/network-bridge" "$@" vifnum=0 netdev=eth0 bridge=xenbr0 > "$dir/network-bridge" "$@" vifnum=1 netdev=eth1 bridge=xenbr1 > "$dir/network-bridge" "$@" vifnum=2 netdev=eth1.1002 bridge=xenbr1V2 > > resulting in the bridges: > xenbr0 > xenbr1 > xenbr1V2 > > Now I can create two virtual machines that use the ''xenbr1V2'' as network > device (network config 192.168.3.0/24, assigned IP .101 and .103) and those > machines can see (and communicate/ping) with eachother. > Another virtual machine uses ''xenbr1'' as network device (network config > 192.168.3.0/24, assigned IP .102). > As expected it is not possible to ping between the machines on the VLAN > bridge and the one on the untagged bridge. > > However I can''t ping the Dom0 from the VLAN tagged machines but I can from > the untagged machines (and vice versa). > I assumed that this might have something to do with routing (since i use > the same network/mask on both nets (tagged and untagged). > So I checked with the routing table. > > with this table i can ping the untagged VM: > Kernel IP routing table > Destination Gateway Genmask Flags Metric Ref Use Iface > xxx.xx.x.x 0.0.0.0 255.255.255.0 U 0 0 0 eth0 > 192.168.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 > 0.0.0.0 xxx.xx.x.x 0.0.0.0 UG 0 0 0 eth0 > > With this table I expected to be able to ping the tagged VM but couldn''t: > Kernel IP routing table > Destination Gateway Genmask Flags Metric Ref Use Iface > xxx.xx.x.x 0.0.0.0 255.255.255.0 U 0 0 0 eth0 > 192.168.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1.1002 > 0.0.0.0 xxx.xx.x.x 0.0.0.0 UG 0 0 0 eth0 > > This might not even be a Xen specific issue but maybe anyone here has/had a > similar configuration and might point me in the right direction. > > Thanks, > Reinhard > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users-- Dipl.-Ing. Reinhard Brandstaedter ZID - Zentraler Informatik Dienst Johannes-Kepler-Universitaet Linz Altenbergerstrasse 69 A-4040 linz phone: +43 732 2468 1368 email: reinhard.brandstaedter@jku.at _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users