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Is it possible to run LAG and STP together? Let's say i want to connect two towers together with an AF24 link and a Rocket M5 AC link. During normal operation i'd like to bond the connections together. When the AF24 fades i'd like all traffic to go on the Rocket M5 AC link.

Or what about capacity aware LAG? 750 mbps on the AF24 and 100 mbps on the AC link. Only put traffic on AC link when AF24 is down or near capacity.

You can use LACP to combine 2 wireless connections together with a WISP switch on each end and it will use both links when they are both up and only use 1 when 1 fails BUT:

I am not sure a wireless bridge would even work with LAGs especially LACP as the bridge may not pass the control packets correctly. I would do a lot of LAB testing and not all wireless bridges would work the same.

LACP or Static LAG will only work if both ports are the same link speed such as 1G and 1G.

LACP is not capable of link congestion and would NOT be aware that link speeds are really less than the 100M or 1G Ethernet link state.

With any switch LAG does not give you a single pipe of 2G from combining two 1 G links but rather divides streams across the 2 links based on the method you select at the top of that Tab such as Source Destination IP, or Source Destination MAC.

If you LAG an airMAX AC PTP link which has a 1G link and an airFIBER 24 that has a 1G port the switch will assume both links can support 1G. lt will work fine and traffic (streams) will be divided up across the 2 links happily until the lessor link becomes full then all hell breaks lose.

You really need to read up on how LACP or Static aggregation works.

Now there is a Priority metric with LACP that may allow you to specify 1 link to be favored over another but this falls apart because a switch will assume a 1G Ethernet link state is actually capable of 1G which with wireless links this is NOT the fact and in reality the capacity varies all the time and the switch protocol will be un-aware of this fact.

Our switches follow the standard with LACP and Static LAG so they work with other routers and switches which are unaware of the random wireless capacity which is LESS than the Ethernet link state that they use to divide up traffic.

So, what is the correct way to do what keefe007 wants? I see others doing it with OSPF. Is that the best way?

wayneorack wrote:So, what is the correct way to do what keefe007 wants? I see others doing it with OSPF. Is that the best way?

Well OSPF is not really aware of link congestion and also thinks that Ethernet link state represents link capacity.

You guys keep trying to apply and use Ethernet protocols that are not aware of link congestion with wireless links that are not represented by the Ethernet Link State.

We all do these things but we have to tweak and experiment and understand limitations and understand what happens when it falls apart.

We have plans to make switches and firmware with special protocols that can deal with wireless link capacity states, switches made specifically for the WISP industry and not the Enterprise industry but all it takes is money.

Please let us get off the ground and raise some R&D money before asking us to create a whole new protocol designed for a vertical market industry.

I wasn't asking for features. Your current product line is loaded with the features I need! I have seen this question/problem several times on the Ubiquiti forum. I was just hoping that there was an easy correct answer....

wayneorack wrote:I wasn't asking for features. I have seen this question/problem several times on the Ubiquiti forum. I was just hoping that there was an easy correct answer....

Sorry, been dealing with support questions all day that make you want to pull your hair out.

Well there really isn't any protocols that do what WISPs want, networking equipment was designed to do things based on the Ethernet link state as an indication of link capacity.

Even with OSPF the router assumes the link capacity is the Ethernet link state but unless you are using OSPFv3 which probably none of you are anyway OSPF uses few metrics to determine which way to route traffic.

Do WISPs use protocols like OSPF and LACP to do things they really should not do....of course, but they really need to play and understand what will happen when link capacity varies from Ethernet link state and what the risks are when doing so.

Is it possible to modify LACP and or OSPF and other like protocols to take into account variable link capacity and detect link back pressure or congestion....you bet it is, it is our intention to develop such gear once we have the budget to do so.

Thank you for the patience and good answer. I am just trying to learn and you are always very helpful!

Thanks for the response. Performant RFLO was the closest thing to what WISPs need. Hopefully you guys can come up with something even better. Do you think it'll work on current hardware with new firmware or will it require different hardware?

Keep up the great work!

No idea, right now we are just trying to get all the products we spent a fortune on to market!