Hi all,
I’m using version 5.2 in a main link (24km): wireless protocol nv2, band 5ghz, dual polarization, radio module ubiquiti dual chain…
I’m very happy to see 85Mbit and low latency..but…i’ve too many problems about reliability.
link radio disconnected every few hours.
link radio get low modulation, from 162Mbps to 82Mbps, unexpectedly and without apparent cause. I usually solve this problem disconnecting manually the wireless registration.
link radio get low ccq, unexpectedly and without apparent cause. We worked hard about this issue but only way to resolve is reboot radios (RB411AH).
Since RoS 4.x I saw more bandwidth but less reliability and availability.
I’m very worried about this trend.
Have got a few long range links using R52Hn with dual ink, starting from around 20km to around 47 km. Haven’t noticed any of the problems mentioned, except for one link that sometimes disconnect at night. We believe the cause to be interference from near by spot lights. Nothing that requires my attention to get it running again.
Yep, n21roadie is right, most likely cause is interference, probably from other TDMA source. Do a scan at both ends (10 and 20Mhz bands) and see what else is using the spectrum… nv2 is very vulnerable for that.
Type “disconnects” in this forum’s search option and you have yourself enough to read the next days…
Rudy - one of your posts requesting a script for saving remote scans would be ideal for this suitation otherwise it will mean a drive out of 24Km for the test, unless from point A or somewhere towards point B (i assume the there is a AP at point B) where using a 23dB CPE to login to that AP and mac-telnet into the ptp and frequency scan.
Hence the urgency of developing a remote wireless scan option that scans all bands and dumps info in txt file for reading/downloading after unit is back online.
It is assured to me such a script is yet not possible but somewhere in the future a solution is to be developped by MT. The more we cry for it the…?
I went to a client this weekend to do a scan and found his CPE picks up in total 16 other AP’s in 5Ghz band. Some in -60 to -70 region and only 10 to 20Mhz away from its own working freq. Most of these AP’s are not ´seen´ by AP so this actually proofs that interferences at client can occure from units the AP cant even ´see´!
But until MT comes with a proper solution (no, not the purchase of a spectrum analyser or fitting of a second unit whe have to live with the inconveniance of physically vist the remote site. How annoying…
There is a way to do a remote scan, it isn’t ideal but it works.
Here is how you do it.
You need to telnet into the client you want to do the scan from.
go to interface/wireless
type the following
scan 0 duration 5s
0 is the wireless interface number and 5s is the length of the scan. You won’t be able to scan much more than 10 seconds otherwise your telnet session will disconnect before the scan finishes.
I already use this. It has some shortcomings though:
you can only scan in the band your radio runs in. i.e. 5, 10 or 20Mhz bandwidth. A radio working in 10Mhz can’t even ´see´ if there is any usage on the 5 or 20Mhz bands. Not even if that happens to be in the same centre freq as that CPE is suppose to work!
If your CPE works in the 10 or 5Mhz band, after a scan the radio takes too much time to find its working freq. back for associating (it ´walks´ through the whole band!). Even a very short ´duration´ of the scan is not enough to bring the unit back in time not to have the winbox session close. And actually you need to scan for some prolonged time too since radio needs to run through all the channels which by itself already takes quit some time.
To overcome the long ´search and find´ process of the radio for its working freq. you can set the working freq. in the wireless ´freq. scan´ field. But in this case the scan only performs in this frequency.
In the 2,4Ghz or 5Ghz-20mhz this is not such a problem. I can do a duration of 8-10 for most routers and the winbox session that has the telnet embedded is not disconnected.
But in the 10 and 5Mhz wide 5Ghz band this is insufficient.
My workaround is that I set in the wireless ´freq. scan´ field the 3 or 5 (2 up and 2 down) adjacent freq. bands of the designed working channel and run the scan in the prescribed way for 8 or 10 secs.
This at least gives me a view on the working channel and 2 or 4 adjacent channels usage..
Off course, if there is another radio working in another bandwidth but with the same freq’s of one of the ones I run the scan in, the radio still won’t see it.
Specially this last item is something I would like to see MT (atheros?) perform. A scan that shows all 802.11 usage in a certain band (2,4, 5, 3.5, 900Mhz etc) no matter if it is a 5, 10 or 20Mhz wide band.
Since radio can receive these all there could be made a option to do this in a scan.
Actually I don’t understand why a scan running in 10Mhz would not pick up a signal that actually runs with a 20Mhz wide bandwidth? The 20Mhz channel is definitely interfering with my 10Mhz radio’s!
Or maybe a scan in 20Mhz should pick up everything, since ´its gate is wide enough to receive all´ to say so
I hope MT reads this and picks it up. I thing it would make ROS an outstanding wireless product!
whe have to live with the inconveniance of physically vist the remote site. How annoying…