414 Request-URI Too Long: Buffer overflow detected

[Machineman]

Sometimes when I remotely try to access my webcontrol board I get this error "414 Request-URI Too Long: Buffer overflow detected".  Most of the time I can access it no problems. Any details on what the issue is?  I use a static IP and no-ip DDNS. I can still access my cameras so it only effects the Webcontrol board.

 

[CAI_Support]

Which exact page do you run into this message?
WebControl has very limited RAM, when the HTTP server could not get enough memory, it will reply this message. It just indicate the memory all in use at that time, so that HTTP request can not be processed.
 
Is your board doing more than one HTTP connection? or SMTP function a lot?

 

[Machineman]

It happens when using a "get" url or trying to log into the status screen.  I only have one smtp command that is rarely triggered. I do have a lot of code and nearly every factory D/I, D/O, and A/I is being used.  Also I have some temp sensors that are showing failure. But the failure is becuase I was messing with it before leaving the site and probably likely didn't get the screw terminals down tight enough.

 

[Machineman]

Is this effecting the execution of the PLC code or just the http access?

 

[CAI_Support]

HTTP server on board is totally separated from PLC logic execution.  HTTP server can only use limited amount memory. If you do a lot of GET calls continously, it may run out RAM for TCP buffer to process the new requests.  Try to put some time delay in between the calls to see if you still run into this problem.
 
Another method to log is to use new WEBSET call to web server that only log when things changing to certain level.

 

[az1324]

Delete your cookies/cache.

 

[CAI_Support]

This CPU has totally 3.8K ram, to have HTTP server, email client, web client, PLC engine, I/O subsystems, TCP and UDP stacks, the amount of RAM for receiving HTTP request is very limited. For protecting all subsystems running correctly, HTTP subsystem can only use so much RAM to accepting HTTP requests.  When that RAM is used up, you will get buffer overran error.  It has no harm, just the HTTP request need to be resent seconds later.

 

[Machineman]

Seems to be working fine now. Might be an intermittent issue. Note this never happened before until I replaced the board with a newer one(v03.02.11) with same plc code. Also on the new board I added the 4.7K resistor mod to reducde A/I noise.

 

[CAI_Support]

Do you like to test our later firmware?
3.02.11 are considered older firmware.  We do encourage users to send board back for update, if the board firmware is older than 3.02.13.
You will get a lot of new features and new funcitons with new firmware.

 

[Machineman]

Do you like to test our later firmware?
3.02.11 are considered older firmware.  We do encourage users to send board back for update, if the board firmware is older than 3.02.13.
You will get a lot of new features and new funcitons with new firmware.

I can swap the board but need to have another on hand since its in service controlling a wind/solar system and some property automation. Do you have release notes on the past few firmware updates?

 

[CAI_Support]

Change log is published on our web site under WebControl product page.