Error: 1, Http Error. Could Not Connect To The Tunneling Url.

[Thrunch]

I've been evaluating using the trial copy. The product seems to be very powerful / good. But I need the HTTP tunneling to work. I'm using the powertool to import from an Access database to a MySQL database over the web. It seems to work fine for small data sets (0 to 300 hundred rows) … but I'm encountering the following problems:

1. I've a table with 4700 rows which it copies completely/successfully but throws up an error “ERROR: 1, HTTP Error. Could not connect to the tunneling URL.”. I've noticed that in the log it has a replace into SQL statement immediately next to the error code that's massive … perhaps the entire 4700 rows.

2. I've a table with 27,000 rows which it copies ZERO rows and throws up the exact same error … with the huge replace into SQL statement (different table of course).

I've examined the PHP error logs on the server … no errors or warnings.

If I synchronize either table without using tunneling it goes ok. So it's definitely related to the tunneling and the amount of data.

[peterlaursen]

It looks like Problem is that your webserver (probably a shared Apache server) fails to serve HTTP requests from SQLyog.  There is no reason why SQLyog should only import a specific number of rows.  

Does it 'break' exactly the same place everytime? If not this can only be solved by the server admin with your hosting.  We have seen before that very cheap (or otherwise bad) hosting overburdens the webserver.  What happens is simply the same as what happens if you refresh a webpage and the page does not load completely.

[nithin]

Hello,

We are providing you a special trial binary where we do some additional logging (in sja.log itself) during Tunneling error. Please try this and attach the sja.log file.

http://webyog.com//downloads/betas/not_released/SQLyog822.1Trial.exe

Thank you

Nithin

[Thrunch]

Thank you for your diligent response Nithin. I have installed your trial version and I have an error log for you that I can send you; however, please email me directly ([email protected]) as I will not post the log to an open forum since it contains a dataset. The data has no identifying information that would make it useful, but there's also no reason to post it here for all to see.

Just to reiterate from my first post, HTTP tunneling is working on every table I've tested except two tables that happen to have 4700 and 27000 records (re-read original post for amplifying details as the problem is 100% replicable). If I synch directly using MySQL (not via the tunnel), the tables synchronize perfectly and completely.

To further verify it is a problem related to the number of records, I tested a synch for both problem tables during which I added a WHERE clause so that they were limited to a 76 row result set (Accounts) and 10 row result set (StudentRecords). In those tests with row counts limited, both problem tables synch via tunneling completely and without error.

With regards to Peter's presumptions on my server … it is Rackspace Cloud which is hardly cheap and cannot be overloaded by such a slight load as this … because it has an entire bank of servers which will dynamically respond to give as much server computing power as needed to meet the load.

Perhaps there is a string limit or post parameter limit you are hitting? I only theorize that because the output SQL in the log is cut off … but that could simply be a limit on the output logging stream.

If you want to send me a version of the PHP with some debug logging parameters, I can easily upload it and that way you can potentially get a monitor of what the server is getting from the SQLyog client.

[peterlaursen]

You can create a ticket and attach here:

http://webyog.com/support/ttx.cgi

The purpose of this logging is that we will consider if we can find a way to make HTTP-tunnel more 'robust' against connection and webserver errors.

[Author]

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