Netonix Forums

Ok I have flow control turned on all Ubiquiti devices and try to turn on the air fibers but the pause frame protect keeps shutting it off. latest firmware. Question is, will the be ill effects leaving it off with all other equipment having FC turned on? Should I keep enabling and wait for it to kick out again?

Mike

Personally I would be careful turning Pause Frame Storm Protection OFF as you may end up driving to site but I suppose you could experiment and let us know?

Maybe pick easy to get to switch so you can simply unplug the AFX radio if it happens and plug it back in which will clear the Storm event

Yeah what I meant was pause protection turns flow control off so what are ill effects of having flow control left off which is the way it has been for awhile now with no problems just didn't know which is better, flow control on with possible pause frame kicking it off or just leaving it off?

update just checked and it says in the log
switch[1312]: got excessive pause frames on port 1 (155770350), count = 1

port 1 is AF management port so does this sort of thing happen?

Mike

With Flow control turned off packets are simply dropped and the TCP/IP end points will request re-transmission.

Personally I like Flow Control on Layer 2 to prevent packet drops on short bursts but UBNT currently has issues with the way they handle Pause Frames but this is new ground and they are working to discover the best way to handle it within the rigid constraints of Layer 2 and make it work with Dynamic Wireless links.

Here is a discussion on the UBNT forums with Chuck where we disagree with the method they are currently using to handle Pause Frames and they are trying to find the best way to handle it as Flow Control and Wireless is breaking new ground on how to properly handle it with it's capacity being so dynamic:
http://community.ubnt.com/t5/airFiber/P ... rue#M30896

You can leave Flow Control OFF on the AF unit or the Switch Port facing the AF unit if you like until they [UBNT] fix their Flow Control but I would not disable Pause Frame Storm protection and ENABLE Flow Control or you may end up running to site.

You are the first to report a Pause Frame Storm on a Management port, I am assuming you are using the Data port for Data and not in-band management?

Yes obviously data port for data I had the extra cable on tower so I plugged in just in case main wire had issues so I could troubleshoot. For now it seems fine with flow off. I reset counters so will keep an eye out for another log of pause frames on management port. I have no errors on that port at all.

Mike

Mike wrote:Yes obviously data port for data I had the extra cable on tower so I plugged in just in case main wire had issues so I could troubleshoot. For now it seems fine with flow off. I reset counters so will keep an eye out for another log of pause frames on management port. I have no errors on that port at all.

Mike

No errors on management port? I would suspect not as not much data is on the management port which I think is only 100M?

Do you have in-band management DISABLED? - YOU SHOULD IF USING THE MANAGEMENT PORT. Not sure how the AF deals with the second port if inband management is selected. Could cause weird issues.

Yes 100 meg port. No errors on that port. I do have inband management enabled but I believe on ubnt forum they said totally separate and it won't cause any issues but someone here may no more.

Mike

That is, it is advisable to disable Flow Control on ports that use AirFiber that's what you recommend