Clarifying some QoS questions

  • Hey guys,

    so i got my fibre 100/100 connection after waiting for that a few years.
    Now that everything is up and running and my little PC-engines APU2 is working pretty fine i wanted to gain more knowledge about traffic shaping and HFSC in particular.

    My configuration looks like:

    APU2_IGB0=WAN = connects to the fibre CPE
    APU2_IGB1=LAN = connects to a 8 port ProCurve switch (several clients, like televisions, computers etc. are attached to that)
    APU2_IGB2=UNIFI = connects to a UniFi access point

    The idea was to shape my traffic and that of my family in a "fair" fashion.
    Obviously i did some research before and read through a bunch of articles about traffic shaping and came across this rather disappointing news:

    shaping for multi-LAN does NOT work as one would expect

    Does that ultimately mean i cannot shape traffic of my lan interface and the interface where my wifi ap is connected to at the same time?
    So even if i would use the Multi WAN/LAN wizard that would let me create queues for such a shaping scenario the only interface that shaping would take place in would be lan?
    Does this only apply to HFSC or to all the schedulers as well?
    So bascially if i want shaping for my entire network, i need to connect everything to one pyhsical interface?? (vlans would still work i assume)
    If that is correct do you mind if i ask, why the wizard offers such a configuration in the first place?

    Thank you for your help

  • It means that your 2 LANs are kinda unaware of what each other is doing, so they can't "share" bandwidth.

    You might try this instead:
    Since limiters can work on traffic transmitted and received from a single interface, you could set it up on WAN and that would effective share bandwidth evenly among your entire network, both upload & download included.

  • @Nullity

    First of all, thanks for your reply. :)
    So if i understood you correctly this does indeed only apply to HFSC cause the whole idea of that scheduler is to share bandwith in a fair fashion among several clients and if thats not gonna happen cause if there are two interfaces which cannot change share their bandwith with each other it contradicts the whole idea?
    But then again this wouldn`t apply to PRIQ where there is no bandwith sharing but just a priorization of traffic, is that correct?

    Thank you

  • @FreeYourMind:

    But then again this wouldn`t apply to PRIQ where there is no bandwith sharing but just a priorization of traffic, is that correct?

    Thank you

    I don't think so because each PRIQ interface is still unaware of any other interface's bandwidth. It's an ALTQ limitation, which all traffic-shaping queue algorithms use (HFSC, PRIQ, CBQ, FAIRQ).

    Also, generally, fair queueing is fair per each flow ("connection") so each host could get an unfair amount of bandwidth by having more flows.

    The limiter approach I linked is much closer to accomplishing your goals. Though, it may not be able to evenly share beyond a /24 network, so you may need to have both of your LANs in the same /24. Dunno… your problem is a common one but I haven't yet ran into a simple solution that I can link you to. :( Good luck. You'll surely learn some stuff along the way.

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