We have now been able to trace to the heart of the problem, though unfortunately still attempting to determine the cause. To give you a rough background, we have a main link that “bonds” 2 Dragonwaves together to form one unit (using the dual radio mount). The DW manual states for this to work when doubling the throughput, it is required to use LACP trunking. We have this in place and it has been working fine up until recently. The trunk is still active (no network loop) however one radio is working more than the other, eventually saturating one of the two links and causing the latency. The second set of radios aren’t performing in terms of actual traffic (signal is ok) but at most they’ve moved 200Mb/s even though they are licensed for 400Mbs.
The link with the LACP has more or less load-balanced itself in the past, however they are now performing very asymmetrical at this point with over a 200Mb/s difference. I understand that LACP does not actively load balance but that’s what has been observed in the past. I suspect the issue is being caused by one of the switches doing the trunking (we just discovered it is unmanageable but still operating, again no network loop). It’s either that or the one leg of the link itself with the low bandwidth usage is not working properly despite indications otherwise. We’ll investigate our theories but always looking for additional input ☺ -Tim From: Af [mailto:[email protected]] On Behalf Of Josh Reynolds via Af Sent: Thursday, October 23, 2014 1:47 PM To: [email protected] Subject: Re: [AFMUG] Dragonwave latency issues You can do a bit more with metro-e style NIDS... those have the layer2 tools to do proper testing. Josh Reynolds, Chief Information Officer SPITwSPOTS, www.spitwspots.com<http://www.spitwspots.com> On 10/23/2014 12:37 PM, Eric Kuhnke via Af wrote: it's going to be really hard to do any meaningful diagnostics with a layer 2 switch on each end, not routers... you could be seeing a broadcast flood of some type. On Thu, Oct 23, 2014 at 1:10 PM, Timothy D. McNabb via Af <[email protected]<mailto:[email protected]>> wrote: Unfortunately there is no QoS and flow control is off on the switches ☹ Dragonwave was contacted as well. No determination yet though. -Tim From: Af [mailto:[email protected]<mailto:[email protected]>] On Behalf Of Peter Kranz via Af Sent: Wednesday, October 22, 2014 1:36 PM To: [email protected]<mailto:[email protected]> Subject: Re: [AFMUG] Dragonwave latency issues Backpressure from the switches in terms of flow-control can show as latency on dragonwave links. Disable any QOS features on the dragonwave if you are using them. Email dragonwave support Peter Kranz Founder/CEO - Unwired Ltd www.UnwiredLtd.com<http://www.unwiredltd.com/> Desk: 510-868-1614 x100 Mobile: 510-207-0000 [email protected]<mailto:[email protected]> From: Af [mailto:[email protected]] On Behalf Of Timothy D. McNabb via Af Sent: Wednesday, October 22, 2014 1:15 PM To: [email protected]<mailto:[email protected]> Subject: Re: [AFMUG] Dragonwave latency issues No routers between, just switches. -Tim From: Af [mailto:[email protected]] On Behalf Of Paul Conlin via Af Sent: Wednesday, October 22, 2014 12:22 PM To: [email protected]<mailto:[email protected]> Subject: Re: [AFMUG] Dragonwave latency issues Could the routers at each end be the limiting factor? What is their CPU utilization when the link is loaded? What happens to latency if you stress the link at 200 Mbps with a speed test? Those radios should be able to do close to 400 Mbps all day long with no latency. PC Blaze Broadband From: Af [mailto:[email protected]] On Behalf Of Joshua Heide via Af Sent: Wednesday, October 22, 2014 3:06 PM To: [email protected]<mailto:[email protected]> Subject: Re: [AFMUG] Dragonwave latency issues Yes it’s a horizon compact Bandwidth of the unit is 400mbs Bandwidth usage between 150-200mbs during peak hours. No QOS Yes during non-peak hours its sits at 1ms SNR 35.00 dB From our prtg graphs this issues has started end of September and latency has gotten worse during peak times as we have deployed more 450 gear to that tower. I currently have HAAM enabled on the link and it stays at 256qam unless we have some bad weather. Josh Heide Velociter Wireless (office) 209-838-1221 (fax) 209-838-1800 www.velociter.net<http://www.velociter.net/> From: Af [mailto:[email protected]] On Behalf Of Bill Prince via Af Sent: Wednesday, October 22, 2014 11:47 AM To: [email protected]<mailto:[email protected]> Subject: Re: [AFMUG] Dragonwave latency issues So it's a Horizon Compact? What is the total bandwidth, and what percentage are you using? Have you set up any QOS? 180 ms sounds like a lot; especially when ours are typically less than 1 ms. -38 is right in the game. What are the other parameters besides signal level? bp On 10/22/2014 11:18 AM, Joshua Heide via Af wrote: We have a dragonwave that has latency issues that coincide with traffic peak times. As our traffic peaks so does that latency at 180ms. Any ideas that could cause this? Signal is -38 Current HAAM Mode hc50_364_256qam Thanks, Josh Heide Velociter Wireless (office) 209-838-1221 (fax) 209-838-1800 www.velociter.net<http://www.velociter.net/>
