LAN Port Aggregation

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    Jason Kopacko

    Have you looked at Ubuntu's core abilities yet? The Firewalla runs on top of Ubuntu, which can support link aggregation. Granted, I just got mine and I have a pair of Cisco 9200's in a switch stack. I have not gotten that far in to the customization options.

    Here's a link that may help you and anyone else wanting to try it.

    https://help.ubuntu.com/community/UbuntuBonding

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    Phil

    @jason, let me explain why I disagree. Your comments are confusing to me when you state that it doesn't matter for the use case I laid out yet you also state that the overall bandwidth increases. That was essentially the use case I identified and I think it was also what you were saying, although differently. Simply saying it doesn't matter I think is an incorrect assessment. If the overall bandwidth increases, then the total data per time is higher. That's what we want.

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    Jason Kopacko

    Again,

    I am not trying to be rude or otherwise. I also did not say that anything didn't matter. My point was, for any individual user on your network. The best possible speed across two network devices that are using link aggregation is the speed of an individual cable. Nothing more, nothing less.

    The speed of the cable is as fast as you can go. So if you had 10 users, downloading a 10-gig file, it will be slower across a single cable versus a link aggregated connection. But each user will still be rate limited to 1-gig. They are not going faster than anyone else. For any TCP connection, all the packets belonging to any individual session/flow will go down the same single link. Otherwise you risk out-of-order packets, which causes serious problems for a lot of applications.

    For any network connection via a link aggregation, the speed does not increase, the throughput does. By being able to accept more flows there is less packet delay. A traffic flow is a TCP connection between two devices. Thus, the speed, or fastest a user can go, is limited by the actual/physical connection.

    I think it is great that many folks here are wanting to do link aggregation, because that is, in my mind, the best approach for any device with high availability needs.
    This is probably a better visualization of link aggregation. The left side, is a serial traffic flow, everyone waits their turn. The right side, is a parallel traffic flow, everyone gets their own lane and go at their leisure.

    In this image, there are 5 users...which way do you want them to operate on your network? Taking turns or all having access? The multi-line (right side) I assume.

    Another person snapped at me about load balancing. Maybe that is where you thought I was being rude or patronizing. I say again, I am not trying to be anything but more concise about what link aggregation is and is not. I am only offering the truth, as Morpheus would say. Load balancing between to link aggregated devices is merely a way of ensuring that one traffic lane doesn't get overloaded while the other 4 lanes sit idle. If there was not load balancing, then having 5 lanes or 20 lanes would make no difference as all the users would still be hanging in the left lane, driving slow, and making everyone else wait.

    I do truly hope that this helps understand the technology better. At the end of the day, we all want the fastest possible for our users.

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