On Fri, Mar 09, 2007 at 01:49:34PM +0530, Niklaus wrote: > Hi, > > I could be wrong in the below description or might have misunderstood > many of the concepts , please correct appropriately. > > 65535 ports can allowed . So on a machine namely C you can have max > 65535 outbound connections
IP connections are quads (four-tuples), machine A and B IP addresses, plus 16 bit port numbers at both ends. You can have about 64 k * 3 G = 192 T connections out from a machine to any single port number out there to all existing IP addresses. If A.ip, B.ip, and B.port stay the same, A can setup up to some 10 - 50 thousand parallel connections. (Depending on allowed dynamic source IP port number space at machine A.) If either B.ip or B.port changes, A can reuse a port that is actively connected to something. Resulting four-tuple is different -> connection is different. Does Linux reuse port numbers in this way ? It most likely does, but I didn't verify. > What i was thinking was to send to another machines A and B from the > same port [X] and then when we get data from it to [X] we can the send > it to the correct application using stateful mapping or storing some > information . The machines A and B are unaware of this mapping from > the C machine. You want to make a "L4 switch" -- a "load balancer" ? That thing is a NAT-box, and is really not making buffered TCP flows, but rather mapping IP/TCP header rewriters to divert the flows to new destinations. > Can we increase it by anymeans in the kernel. Does we have patches for the > above > > i read on the web that terry lambert has got 1.6 million simultaneous > connection ? how is the way it is done. > > http://kerneltrap.org/node/277 With 50 thousand connections per single ( A.ip / B.ip / B.port ) set, one needs only 32 B.ports or A.ip:s or B.ip:s to do that 1.6 million parallel TCP streams. Such does eat up lots and lots system kernel memory... > Regs > Nik /Matti Aarnio - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/