Multi-line bonding

RouterOS General
1

I have several lines, T-1s and XDSL. I have finally gotten my upstream provider to allow me to attempt to bond several lines together for a fat pipe vice several small pipes…

They have a state of the art Cisco sitting there…can MT in a bonded config, bond with the Cisco to bring all the pipes together at the same time, or will it require that I use an MT box there as well to bond the lines?

Would EoIP work better w/the Cisco or the MT in achieving the above goal?

I have been a long time wireelss user of MT products and fancy myself fairly well versed in it’s use. This is just a little out of where I normally work so I am fishing for some hints before I dive in.

Please don’t send links from the wiki or the user manual, I’ve read them all, and I’ve read every post that either deals w/bonding or EoIP and really they are all half answered with no tangible answers/configs/results attached.

2

We’ve just done quite of bit of experimentation with bonding. This URL will help you understand their implementation more:

http://linux-net.osdl.org/index.php/Bonding

That said - here are some quick things.

  1. Bonding will only work with MT (or possibly another linux bonding endpoint per the above URL).

  2. Note that your max speeds will only be the # of devices * the slowest one of the links. For instance, a set of cable modems at 512k, 512k, and 1024k will only give you 1.5mb, not 2mb. This is because of round robin, each packet goes out the next slave.

  3. TCP retransmissions and packet reordering … it can be a big problem in some cases. You might see 20-30mb and then all of a sudden you see 10mb. TCP will throttle to make sure everything is correct. UDP has no guaranteed delivery, so its possible for packets to arrive out of order and cause voip or other udp services problems. This could be a killer, depends on what your use is of the bandwidth.

  4. You can only bond ethernet interfaces. We bonded 3 l2tp tunnels running on 3 cable modems using EoIP on top of l2tp. All 3 EoIP tunnels became slaves.

Either way, its pretty cool to get faster bandwidth even if its not perfect.

PS - If anyone is interested in using MT in a bonded scenario using our bandwidth let me know offline. We’re hoping to offer it as a service in the future but we need testers.

Sam

3

Thanks Sam - good info on the URL about bonding.

We may just have to use EoIP - we use VoIP quite a bit…

I will try to post results to this post later (say a month or two)

Anyone else?

4

changeip - could you drop me a line off forum?

thom.lawless@rapidwifi.com

Thanks.

Thom