Bad bufferbloat on WAN link. How to shape with Fortigate
Hi all,
Have recently started a new contracting gig. part of the role is implementing a voip telephone system , and I've been investigating the network a little as there are some problems with jitter and large latency spikes to handsets. Anecdotally users are also reporting "slow" internet , often when we are no where near peak capacity.
a (not managed by us) telco router/media convertor is onsite (either one or both , I see a cisco MAC from the fortigate WAN interface, its near the MDF in the building, which we don't have access to) . with a 50/50 fibre link.
RRUL testing shows pretty bad bufferbloat
I'm not very familiar with fortigate products, I don't see any option for fq_codel , HTB etc as such , which I have had some success implementing on linux based routers etc before.
Im thinking much of this problem is either because of how the ISP internet gear is buffering traffic (if its a router I can see in ARP), or its just discarding everything above 50m. I see spikes over 50mbit when the link is saturated that drop off quickly, I dont think they are letting us burst traffic though, I think its just being dropped so I need to setup some shaping outbound.
There is pretty much zero setup on the fortigate right now from the outfit that installed it. No QoS. There are Vlans but they do nothing except have slightly different subnets (all route to each other, no tagging or QoS). There are stacked DELL switches attached to the LAN, everything in the office goes through these.
Anyone have some experience trying to solve this on fortigate gear , or some tips on config?
in the past ive worked with mid band ethernet type services where its fairly essential to shape traffic before handing it off to the NTU ( a dumb layer 2 device thats just mirroring the mac from the switch in the exchance). I'm thinking if I can just shape everything at the LAN interface to slightly less than 50 this will improve, then I can work on QoS for the voice vlan etc.
Any ideas or tips? I think we can get much better performance from this service.