load balancing on 3 DSL lines?

Discussion in 'Cisco' started by al, Apr 21, 2004.

  1. al

    al Guest

    Hi all,
    My client purchased a Cisco 2600 with NM of four ethernet ports.
    He will start by connecting three ethernet ports to three different DSL
    lines.
    What kind of load balancing can we achieve by doing this?
    Can we configure the router with three "ip route 0.0.0.0 0.0.0.0" pointing
    to three different default gateways and achieve load balancing?
    What about QOS, if we want only FTP on the first DSL line and HTTP traffic
    only to the second line, can that we achieved also?
    Please advice.
    Thanks,
    Al
     
    al, Apr 21, 2004
    #1
    1. Advertisements

  2. Don't see why you would want to, unless.. but whatever
    Just give it the same metric. (ip route 0.0.0.0 0.0.0.0 <gatewayip>
    <metric>)
    Better hope it's the same network at the other end :p
     
    Sartan Dragonbane, Apr 21, 2004
    #2
    1. Advertisements

  3. :My client purchased a Cisco 2600 with NM of four ethernet ports.
    :He will start by connecting three ethernet ports to three different DSL
    :lines.
    :What kind of load balancing can we achieve by doing this?
    :Can we configure the router with three "ip route 0.0.0.0 0.0.0.0" pointing
    :to three different default gateways and achieve load balancing?

    Unless the ISP is actively cooperating by supporting BGP (or equivilent),
    or the ISP is one of the rare ones that supports MLPPP over DSL,
    then the kind of load-balancing you can configure is to have some
    degree of control over balancing of -outgoing- packets, but no control
    over -incoming- packets.

    You can't just order up <N> lines and expect to be able to do
    bi-directional load balancing: keep in mind that as far as the other
    end is concerned, only one of the <N> links is going to have the return
    route for your network block.

    I am being a little harsh, though: if you arrange NAT on the <N>
    lines so that the outgoing packets on the lines have source addresses
    that are publically routed to that line, then at least the replies will
    go back to the same line. That's not particularily good load balancing
    once you get into big ftp's or http replies...


    :What about QOS, if we want only FTP on the first DSL line and HTTP traffic
    :eek:nly to the second line, can that we achieved also?

    You still have the return-address problem: unless you arrange with
    the ISP or you do tricks like the NAT I mention, then all replies
    are going to come back through one single connection. But you don't
    need QoS to send different kinds of traffic to different interfaces:
    you use policy routing for that.

    The phrase "my client purchased" suggests to me your client bought used
    equipment (and perhaps might not have a legal right to use IOS), and
    that possibly you are speaking of a true 2600 rather than a 2600XM.
    If so, there might be an older IOS on it. You might want to double
    check with the Feature Navigator that all the policy routing clauses
    you need are supported on that model in that IOS version.
     
    Walter Roberson, Apr 21, 2004
    #3
  4. al

    chad Guest

    The following would work on T1 lines, not 100% sure about DSL:
    As far as the FTP and HTTP, you will need to use acl's and apply them to the
    appropriate interfaces. For the rest of the traffic, you would need 3
    default routes, CEF enabled and the 'ip load-sharing per-packet' on each
    interface.
    For return load-sharing (service provider to you), all 3 connection will
    need to terminate on the same service provider router to achieve
    load-sharing.
     
    chad, Apr 21, 2004
    #4
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.