Hi, few weeks ago I asked question that was probably not interesting for you. Now ill put it differently. 2 computers - VPC and HOST VPC has 2 eth0 and eth1 interfaces (on host tap1 and tap2) HOST has 1 tap (tap0) HOST has br0 where tap0 and tap1 are bound VPC has br0 where eth0 and eth1 are bound tap1 has ip br0 on VPC has ip ping from VPC -> tap1: __ratelimit: 32575 callbacks suppressed eth0: received packed with own address as source address eth0: received packed with own address as source address eth0: received packed with own address as source address ... infinity loop stopped by command to turn on stp on VPC. This blocks eth0 -> port connected to bridge on HOST. No more problem with loop and VPC can actually ping HOST. Probably using eth1 which is not connected anywhere. So I assume that once packet is somewhere on a tap interface in the HOST. Thus its not possible to do little complicated network because all taps create a loop no matter how user connects them in bridges...is that right? I've lost big amount of time trying to make this working...so please make sure i dont lost even more :)) Thanks Radim On Mon, Nov 23, 2009 at 11:12 PM, Radim Roska <radim.roska at gmail.com> wrote:> Hello, > > I have this very uncommon situation :). My diploma thesis will probably be > playing with linux kernel in various networks. Currently I have little free > time and limited computer resources -> only one laptop :). But I would like > to do some profiling of kernel particularly of bridging part. For that i > need network. > > So i have 2 virtual machines VPC1 and VPC2 (running debian) > > HOST - VPC1 - VPC2 > > VPC1 should act as bridge. > HOST: tap0 interface > VPC1: > eth0 ~ tap1 on host > eth1 ~ tap2 on host > VPC2: > eth0 ~ tap3 on host > > how to connect it? :) Well tap0 - tap1 is in br0 on host and tap2 + tap3 is > on br1. > > VPC1 than has eth0 and eth1 in bridge also :). > > I know..it looks strange..but i thought its simplest :). > > But: > > 1) although VPC2 is connected through br1 that has connection only with > tap2=eth1 on VPC1..I can ping anything even when VPC1 has all interfaces > down > > 2) i dont see any loop in my "network" but anyway once i turn on br0 > without stp on VPC1, i got quite a serious perf problem - little storm i > guess:). > starting stp solves storm but disables eth0 > [ 3839.200640] br0: starting userspace STP failed, starting kernel STP > [ 3839.201388] br0: topology change detected, sending tcn bpdu > [ 3839.202117] br0: port 2(eth0) entering blocking state > > i does not matter if i have stp on HOST's br0/br1 > > If someone would have time to help me with that I'll be very happy :). Its > possible Im trying approach that is doomed to fail because i dont > know/understsand something. > > Cheers, > Radim >-- Radim Ro?ka -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.linux-foundation.org/pipermail/bridge/attachments/20091205/759424c2/attachment.htm
Radim Roska wrote:> Hi, > > few weeks ago I asked question that was probably not interesting for you.I don't know for the other readers of this mailing list, but even after reading both posts twice, I still don't understand what you are trying to do. This might be the reason why you didn't received any answer for your first post. Please, do not only focus on you setup, but also describe the expected effects. Nicolas.> > Now ill put it differently. > > 2 computers - VPC and HOST > VPC has 2 eth0 and eth1 interfaces (on host tap1 and tap2) > HOST has 1 tap (tap0) > > HOST has br0 where tap0 and tap1 are bound > VPC has br0 where eth0 and eth1 are bound > > tap1 has ip > br0 on VPC has ip > > ping from VPC -> tap1: > > __ratelimit: 32575 callbacks suppressed > eth0: received packed with own address as source address > eth0: received packed with own address as source address > eth0: received packed with own address as source address > ... > > infinity loop stopped by command to turn on stp on VPC. This blocks eth0 > -> port connected to bridge on HOST. > > No more problem with loop and VPC can actually ping HOST. Probably using > eth1 which is not connected anywhere. > > So I assume that once packet is somewhere on a tap interface in the > HOST. Thus its not possible to do little complicated network because all > taps create a loop no matter how user connects them in bridges...is that > right? > > I've lost big amount of time trying to make this working...so please > make sure i dont lost even more :)) > > Thanks > Radim >
Hi :), sorry Nicolas, sending it again because last time i forgot to include bridge mailing list.> On Sat, Dec 5, 2009 at 7:29 PM, Nicolas de Peslo?an < > nicolas.2p.debian at free.fr> wrote: > >> >> I don't know for the other readers of this mailing list, but even after >> reading both posts twice, I still don't understand what you are trying to >> do. >> > >> This might be the reason why you didn't received any answer for your first >> post. > >ok..that could be the reason :)> >> Please, do not only focus on you setup, but also describe the expected >> effects. >> > >I want virtual PC to have working bridge from its eth0 and eth1 interfaces. Thats all :). Eth0 would be connected to host and eth1 e.g. to another virtual PC. I tried to explain problem in detail but maybe i just concealed this simple desire:) -- Radim Ro?ka -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.linux-foundation.org/pipermail/bridge/attachments/20091206/aefcc5af/attachment.htm
Radim Roska wrote:> Hi,Hi Radim,> few weeks ago I asked question that was probably not interesting for you. > > Now ill put it differently. > > 2 computers - VPC and HOST > VPC has 2 eth0 and eth1 interfaces (on host tap1 and tap2) > HOST has 1 tap (tap0) > > HOST has br0 where tap0 and tap1 are bound > VPC has br0 where eth0 and eth1 are bound > > tap1 has ip > br0 on VPC has ipHere is what I understand from your last post: +----------------HOST-----------------------------+ | | | ???? --tap0--+ | | | | | | | | +--br0 | | +-----VPC-------------------+ | | | | | | | | | +--eth0--|--tap1--+ ip here | | | ip here br0--+ | | | | +--eth1--|--tap2 | | | | | | +---------------------------+ | | | +-------------------------------------------------+ Can you confirm ? Please extend and possibly fix this ascii art to include you whole setup. If this is correct, then, the first possible problem comes from the fact that you should not put an ip on a member of a bridge but on the bridge itself. (br0 on HOST, not tap1 on HOST). Also, can you describe what you plan to do with tap2 on HOST and what process is managing the user-space side of tap0 on HOST ? Is it another VM ?> ping from VPC -> tap1: > > __ratelimit: 32575 callbacks suppressed > eth0: received packed with own address as source address > eth0: received packed with own address as source address > eth0: received packed with own address as source address > ... > > infinity loop stopped by command to turn on stp on VPC. This blocks eth0 > -> port connected to bridge on HOST. > > No more problem with loop and VPC can actually ping HOST. Probably using > eth1 which is not connected anywhere. > > So I assume that once packet is somewhere on a tap interface in the > HOST. Thus its not possible to do little complicated network because all > taps create a loop no matter how user connects them in bridges...is that > right?It is possible to do complicated network using VM and tap devices. Several tap devices are not leaking between them. But, if your configuration end up with two bridges face to face (one in the VM and one in the HOST) with two links between them, then you must enable stp on both bridge, in order to allow the bridges to detect and "fix" the loop. 'hope this help. Nicolas.> I've lost big amount of time trying to make this working...so please > make sure i dont lost even more :)) > > Thanks > Radim > > > > On Mon, Nov 23, 2009 at 11:12 PM, Radim Roska <radim.roska at gmail.com > <mailto:radim.roska at gmail.com>> wrote: > > Hello, > > I have this very uncommon situation :). My diploma thesis will > probably be playing with linux kernel in various networks. Currently > I have little free time and limited computer resources -> only one > laptop :). But I would like to do some profiling of kernel > particularly of bridging part. For that i need network. > > So i have 2 virtual machines VPC1 and VPC2 (running debian) > > HOST - VPC1 - VPC2 > > VPC1 should act as bridge. > HOST: tap0 interface > VPC1: > eth0 ~ tap1 on host > eth1 ~ tap2 on host > VPC2: > eth0 ~ tap3 on host > > how to connect it? :) Well tap0 - tap1 is in br0 on host and tap2 + > tap3 is on br1. > > VPC1 than has eth0 and eth1 in bridge also :). > > I know..it looks strange..but i thought its simplest :). > > But: > > 1) although VPC2 is connected through br1 that has connection only > with tap2=eth1 on VPC1..I can ping anything even when VPC1 has all > interfaces down > > 2) i dont see any loop in my "network" but anyway once i turn on > br0 without stp on VPC1, i got quite a serious perf problem - > little storm i guess:). > starting stp solves storm but disables eth0 > [ 3839.200640] br0: starting userspace STP failed, starting kernel STP > [ 3839.201388] br0: topology change detected, sending tcn bpdu > [ 3839.202117] br0: port 2(eth0) entering blocking state > > i does not matter if i have stp on HOST's br0/br1 > > If someone would have time to help me with that I'll be very happy > :). Its possible Im trying approach that is doomed to fail because i > dont know/understsand something. > > Cheers, > Radim > > > > > -- > Radim Ro?ka > > > ------------------------------------------------------------------------ > > _______________________________________________ > Bridge mailing list > Bridge at lists.linux-foundation.org > https://lists.linux-foundation.org/mailman/listinfo/bridge