basically what we want to do is have a 2 backhauls receiving signal from two different towers, obviously, in case we lose link on one, we can automatically switch to the backup. Can i plug 2 back hauls into a ‘redundant’ router and plug my CMM into one of the ports? if so, is there anything i need to do special with the router?
There are two basic ways to do this.
One is by using intelligent switches supporting some variation of the Spanning Tree Protocol. STP will detect that one link is active and automatically suspend the second link. If for some reason the first link fails, the second one will be brought back up.
The other is by using routers that support a routing protocol like BGP. This will work by having a preference of which link should be used for traffic and announce the IP addresses behind it. So if both links are up, it will send to that remote router over that first link that your customer’s IPs are reachable there. If the first link fails, then it will start announcing your customers as behind behind the second one.
http://en.wikipedia.org/wiki/BGP
http://en.wikipedia.org/wiki/Spanning_tree_protocol
ok. thanks for the help. which way would you recommend
stp or rstp would probably be quicker for failover but both will work, with bgp you have to have a router that supports it. you can get a mikrotik rb450 which can do rstp, stp, or bgp and can be used as a router, switch, or both. however you set it up.
Cheapest and easiest to set up would be STP or RSTP indeed. A decent switch that can pull this off is pretty cheap.This will also allow you to keep your network bridged if you do not want a router in there.
gotcha, what brands and models has anyone has used? i know mikrotik is good stuff, but i am kind of looking for something a little easier to figure out…heh… any particular ones to stay away from? thanks for all the help 
anyone???
Cisco is pretty much the standard here. If you’re fine with 100 Mbps switches Catalyst 2950s can be had for very cheap on eBay - I’m seeing a 24-port one at $50 USD.
Also found this in a quick Google search: http://www.cisco.com/en/US/docs/switche … wmstp.html
As soon as we get the wireless side in place we are planning on implementing a similar setup, though possibly with 3500s, or whatever we happen to order.
This is the best solution if you are going to have two hot links: http://en.wikipedia.org/wiki/EtherChannel
Both are active giving you double the BW. If one fails, the other is still live.
Etherchannel and LACP are not good solutions for this if they will even work at all. They are designed to work over the wire (or fiber) directly between two ethernet devices and do not function over bridges, and definitely not bridges which you’d still want to have management access to
Interesting.
thanks for the info.