Intermittent Connectivity Drops

3-4 months ago we begin to deploy CN201p units as endpoints for our 30x30 and 60x60 fiber to the premise clients. We are experiencing a very high number (almost 100%) of reports of these installations losing Internet and SIP connectivity for time periods of 30 seconds to 3 or 4 minutes. This is reported to ocurr several times a day (they tell us 5-10 times a day)

Field techs going to investigate always find the 201 inaccessable via the web interface when they arrive. 2 different conditions noted when trying to access the 201 via html interface. Either see a text formated screen or the html interface screen is present but it will not repsond to the known access credendials. Upon power cycle the unit is again responsive as should be.

We are seeing this issue very consistently and continue to investigate.  We have tested the fiber circuits extensively and see no issues there. We are also seeing some number of these same reports from our Wireless customers especially businesses on higher throughput levels.

There are 2 things we have seen that seem to make these issues disappear. #1 is that we schedule a reboot from within the 201 for 2-3 times per week. #2 is that in 2 of these installations we replaced the 201 with a competing product  (DrayTek) and the issue vanished.  It if far preferable for us to use the 201 as out entire network is Cambium based and we are beginng deployment of Maestro and need this as our management tool.

We have encountered these reports on units with no ATA provisioned in the 201. With ATA provisioned in the 201 and with and without Grandstream 4 port ATA behind the 201.

We are not comfortable with programmed reboots of this number of times.  

Anyone else experiencing this issue? 

Hi Rick ,

We have not found such behaviour coming from R201 devices . could you please get syslog of these devices when they

exhibit such kind of problem and send to us . we will immediately start further investigating this .



you should secure your units. i'm going to guess you've got a public IP in them, or 1:1 nat allowing direct access. 

in your administrative settings, restrict access to your WAN interface by IP range maybe use the entire scope if you want, but try and make the range as small as possible and use a complicated password.  

i've seen that happen to a few routers who are getting beat to death is bad sessions trying to access them, or the password is guessed but getting a stream of bad commands sent to its command line. 

also be wise to use non-standard ports if you are not already with the restricted wan access.

port 7080 for http, 7443 for secure and 2222 is easy not in use ports to remember.

We have all Cambium Routers and last two weeks we have been seeing some routers just lock up. The lights are still flashing like its tranmitting data but no data is Passing through the unit. Once we reboot the router it takes 2-3 mintes and starts working again for about 6-10 hours then does the same thing. We put a heat gun on the units and the Temp is ranging on the back of the unit anywhere from 119 to 125 degrees. 

Is anyone else having this same problem?