On Tue, 22 Oct 2013 16:27:02 -0700 Dave Taht <[email protected]> wrote:
> On Tue, Oct 22, 2013 at 4:12 PM, Stephen Hemminger > <[email protected]> wrote: > > With TC you can apply an action to packets coming in. > > One of those actions is mirred (not a typo) which mirrors the packet > > to another device. There is both mirror and redirect possible. > > > > Jamal invented this years ago, but actions are not widely used. > > I use this technique for an input redirect into ifb for cerowrt's > shaper. It works > well. > > > Inside Vyatta CLI wrappers, the port-mirroring capability converts to tc > > commands. For example doing SPAN equivalent from eth0 to eth1 is: > > > > tc filter add dev eth0 parent ffff: \ > > protocol all prio 10 u32 \ > > match u32 0 0 flowid 1:1 \ > > action mirred egress mirror dev eth1 > > In this case the device on eth1 would have to be an entirely passive > device otherwise it will attempt to interact with that traffic (?) In > the case of cero, it has two ethernet devices available, one hooked > directly into a switch, and as many wifi ones as you want. What would > probably work would be to split off a dedicated vlan port for the > mirror and send stuff to dev eth1.4 - (for example) so long as the > listening server was entirely passive. Yes, eth1 was assumed passive. > > tc filter add dev sw00 parent ffff: \ > protocol all prio 10 u32 \ > match u32 0 0 flowid 1:1 \ > action mirred egress mirror dev se00.4 That should work but doing mirror from se00 to se00.4 would create a death spiral. > > but you'd also want to do it on ingress too. (?) > > I forget the syntax for splitting off a vlan port in cero... > > > The actions apply to a filter, and this seemed to be a workable (match all) > > filter. > > Both directions? This was done on ingress only. _______________________________________________ Cerowrt-devel mailing list [email protected] https://lists.bufferbloat.net/listinfo/cerowrt-devel
