Hello everyone. I have installed a PtMP net with one AP and 2 clients over 10Km away. The problem is that after some hours randomly one of the clients (or both) seems to be dropped but not deassociated (in the registration-table existswith good signal). They seem to be connected with good signal but I cannot ping them or connected through mac-telnet. When I reboot the ap everything goes back to normal. Temporally, I have scheduled for hourly reboot, but I dont thing this is the solution. Any suggestions?
No encryption is used.
Signal is about -70db for all clients.
ROS version is 5.14 for the ap and 5.18 for the clients
Also, instead of a reboot, you can probably just re-enable the wireless interface. (When you enable it when it is already enabled, it still resets it… you normally don’t have to disable it first).
The AP consists of a PCEngines with Atheros miniPci AR5213, but I dont this this is the problem since I have used dozens of them with the same setup and never had a problem.
Nice tip! But only as a temporary solution.
I’ll try to get and post some logs for this problem
It happened again but the logs didn’t capture something.
But I see a strange thing in the clients that are dropped. In the registration-table the rates are abnormally high in 54Mbps (both tx and rx). This shouldn’t happened with this pour quality of signal.
When I re-enable the interface the rate comes back to normal (18-24Mbps) and the connection comes back.
Does anyone knows why it doesn’t re-calibrates?
PS. I disable the rates over 24Mbps and I’m waiting to see if it happens again.
Can you recall the CCQ was before the data rates were reduced also what gain is the CPE’s, if problem still occurs you could try changing AP frequency.
Thanx for the reply. The CCQ before the reduction was about 60-80%.
The AP has a panel antenna with about 19dbi and the clients have grids with about 32dbi. All the cards were configured with about 20dbi tx power.
What frequency are you using for the AP, the grid has a frequency bandwidth of 5470 - 5850 MHz, not sure when radio card manufacturers quote High power design with average power of 23dBm and peak power up to 28dBm but do not supply a detailed technical infromation which could mean the card is maybe working at 17dbm or lower at 54Mps, to date i have used XR5 radio cards which give 23dbm @ 54Mbps and higher when data rate is reduced.
The freq is 5700. Since I dropped the rates the problem solved, but I wonder shouldn’t the card drop the rate automatically? Why it stacks in the 54Mbps while it can’t support it?
With a higher power radio card you will give higher sustained data rates + CCQ, also signal fade variation must be allowed for with any wireless connection.
If you want to have have a stable wireless connection : then CCQ must be very high, nzikos had 60 -80 % before data rate reduction now he reports 100% and this solved his issue, I don’t understand ..its RouterOS problem.. as he is not using NV2 and it must not be interference so what do you suggest the issue is?
His problem was wlan stop transmitting data need disable/enable wlan interface or reboot RB
if CCQ or signal is low or there is interference throughput should be low or clients should disconnect and reconnect or something similar but never should wlan stop transmitting data
I have same problem where CCQ is 90/100% signal of clients from -51 up to -65
soddenly wlan stop transmitting rx/tx data (2-3 times a week)
I reported this problem since MT 5.15 (when wlan freeze 2-3 times a day) now its better but not fix totally yet
Can i ask have you used a RF spectrum analyzer to scan 4.9 to 6 GHZ for rf interference, also how clean and stable is the AC voltage is it 110/230v a clean sinewave, is there hash or intermittent spikes on the ac incoming supply and after it’s converted to DC is the DC supply clean, are you using UPS supply for the routerboards.
I didn’t use anything beyond the frequwncy-usage, But the area is very clean and I have other links in the same area with out problems.
Since I have manually dropped the rate to 24Mbps the problem disappeared.
This is a very common misconception, you are scanning for other 802.11 compliant devices on licence exempt frequencies and other devices could be on or near the frequency you assume is clean as they do not show up in this type of scan, a RF spectrum analyser with an appropriate antenna will scan the band you want to use and reveal all users on this band. http://www.spectran.com/Handheld_Spectrum_Analyzer.htm