4 x ePMP2000 Total Frame time used 100%

Would appreciate any suggestions. Has been struggling for a few weeks now with this. Concluded, either it is something on firmware 4.4 and Flex mode or series interference. Have four ePMP AP's on same site with same issue. When the Ethernet speed reaches around 25 MB/s on an AP, we start hitting 100% utilization. Do go up to 30Mb/s on the AP Ethernet side, but then the SM only get up to around 2MB/s download speeds. Upload always seem to be fine, but guising just because utilization is not that high. As indicated has 4.4 image installed on AP and SM. The SM's connected to an AP is between 25 to 30. Early morning we would get around 30MB/s download speed per SM in Flex mode. In after noon around 4 when usage pick up this drops, which is logical since Utilization hits 100% All AP's have different freq. Have changed them numerals times. SM signal lows 47db to just under 70db for high. SM with 47db signal does get bit better download speed, up to around 4MB/s. Do have around 5% download retransmit packets, Was higher but this is after setting download Max rate to MCS12. Also changed the Cambium 120deg sec with 60deg RF Element sectors. Do not detect any interference on eDetect. Did also run al AP's in GPS sync mode 75:25 but had same problem. As work around i am going to add more sector tomorrow. Try and get the bandwidth load down per sector, I am running out of ideas. :-) Appear to be something common to all AP's, hence the software question. Upgraded to 4.4 about a month back. Any suggestions would be appreciated.

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Hi.  just for clarity... you use both MB/s and Mb/s in your description.  Did you mean Megabit in all cases, or were some of them MegaByte?

Also, have you tried 4.4.2?  You say you're on 4.4, and I obviously there are bugs which have been fixed between 4.4 and 4.4.2 now.  I don't know a specific bug which account for this, so that may have zero to do with what you're seeing - but it's generally good practice to be on the latest release version when troubleshooting, just in case you're tickling some bug which has already been found and squished in 4.4.4  :D 

Hi,

Let me ask couple questions

1. You mentioned 4 x ePMP2000 in the subject. Do you have frequency reuse? How the frequency planning is done? What is the configuration?

2. Are you running flexible mode? If so frame utilization doesn't mean a lot, cause the system will always try to make a 100% loaded frame. We shall remove frame utilization for flexible mode in order not to get you confused.

3. Are you telling you have 25Mbps coming in from Ethernet and only 2Mbps going to wireless?

Do go up to 30Mb/s on the AP Ethernet side, but then the SM only get up to around 2MB/s download speeds. 

In any case it is a good idea to open up a support ticket, share the tech support files and let our engineers help you.

Thanks,

Dmitry

Hi

Ok, did upgread all firmware to 4.2.2

1. You mentioned 4 x ePMP2000 in the subject. Do you have frequency reuse? How the frequency planning is done? What is the configuration?

No, do not re use freq. Was configured TDD AP, Flex mode, 20Mhz, 2.5ms, short guard interval and Max rate set to MCS12

2. Are you running flexible mode? If so frame utilization doesn't mean a lot, cause the system will always try to make a 100% loaded frame. We shall remove frame utilization for flexible mode in order not to get you confused.

Yes, flex mode. Also found flex mode, double "wireless link test speed" on Cambium, but true throughput as almos half of indecated speed. Is correct in GPS sync mode, though. Ok, might be barking up the wrong tree then. The only problem I could find, was that utilization is 100%.

3. Are you telling you have 25Mbps coming in from Ethernet and only 2Mbps going to wireless?

Do go up to 30Mb/s on the AP Ethernet side, but then the SM only get up to around 2MB/s download speeds. 

Yes 25Mbps on ethernet but this would be distributed to the SM's connected to the AP. 2Mbps is max throughput toa spesific SM. The other SM's will have lower throughput on wireless speed test. In the morning when this is around 10 Mbpson the Ethernet side, the wireless link test to a spesific SM is from 20Mbps to 30Mbps dependent on signal strength, however in the afternoon when traffic pick up to around 25Mbps max around 30mbps on Ethernet side, if I do a wireless link test to the same SM, I would be lucky to get 2Mbps on the test. Does not seem to differ, whetherit is a SM with a 50 dB signal or a 70db signal.

Started envestigating our other sites and they are all behaving in the same manner. Some of them only have one ePMP2000 with a 120deg cambium antenna and smart antenna. I have this morning changed the five ePMP2000 to GPS sync at 50/50 ratio, added an AP, just to ensure this is not self interference.

In any case it is a good idea to open up a support ticket, share the tech support files and let our engineers help you.

This will be my next course of action, just had to confirm this is not something wrong on our side.

Thanks

Lourens

Yes, it doesn't sound right for 20MHz channel and 25Mbps of aggregate throughput. Please open up a support ticket.

Thanks,

Dmitry