Hi, Willy Tarreau <[email protected]> wrote: > Hi Maik, > > On Tue, May 12, 2009 at 01:57:47AM +0200, Maik Broemme wrote: > > Hi, > > > > I have a small question. Did someone know if it is possible to do simple > > traffic multiplexing with HAProxy? Maybe I am missing it somehow, but > > want to ask on the list before creating a patch for it. > > what do you call "traffic multiplexing" ? From your description below, I > failed to understand what it consists in. >
Multiplex means traffic duplication. If you have multiple server configuration options in one listen group, the incoming traffic is sent to all servers. > > Just to answer the real-world scenario question. TCP multiplexing can be > > very useful for debugging backend servers or doing a simple logging and > > passive traffic dumping. > > > > There are two major ideas of implementing it: > > > > - 1:N (Active / Passive) > > - 1:N (Active / Active) > > > > Well active means that request is going to destination and response back > > to client and passive means that only request is going to the destination. > > In configuration it could look like: > > > > listen smtp-filter 127.0.0.1:25 > > mode tcp > > balance multiplex > > server smtp1 10.0.0.5:25 > > server smtp2 10.0.0.6:25 > > > > The active / active would be very hard to implement, tcp stream > > synchronisation would be a pain and I think no one will really need > > this, but active / passive is a very useful feature. > > > > In my environment it is often so, that developers need access to real > > traffic data to debug (in the example above) their developed smtp > > software. Is anyone else missing such functionality? :) > > Access to real data is solved with tcpdump or logs, I don't see what > your load-balancing method will bring here. > tcpdump is not perfect in that case, because it has to run the hole time you want to duplicate the traffic and sent it to server1 and server2. > > --Maik > > Regards, > Willy > --Maik
