File Corruptions

[laura_c]

Hi All,

 

For about a month now we have been getting increasing frequency of corrupted files on our site. The corruption seems to be taking place during the FTP transfer of files up to the server - which takes place automatically several times a day.

 

The pattern of file corruption appears to be random. Sometimes no files are damaged, sometimes several. We also get no warning that such a problem has occurred. The only time we find out is when a customer tries to access one of the shop products that uses that file.

 

I have two questions if anyone can answer them please:-

 

* has anyone had this issue before and if so how did they solve it?

* is there a log file somewhere after each FTP session that I could examine to see if something untoward has occurred? if so can someone point me to where to find such a file or how to enable such a log file to be kept.

 

I have not raised this as a ticket, mainly because I'm not sure if it is a TCH problem or something on my PC. So hoping someone can steer me in the right direction.

 

Thanks,

 

Laura

[TCH-Thomas]

First thing I would try, is to try a few of the files that people have reported as corrupted on my own computer, providing I had the originals of those files. While you don´t say which file formats these files are, if it´s a movie then try play it, if it´s a zip file try to extract it etc.

 

If it works on your computer when trying this, something happens either on the way to the server or on the server.

To see if it´s on the way to the server, I would try different ftp programs to upload them. If they still are corrupted when downloaded, then ask the techs to look into it.

[laura_c]

Thomas,

 

Thanks for taking an interest in this and for your suggestions.

 

The files are not corrupted on the PC - we run Kaspersky and have recently downloaded MalwareBytes, both of which give us a clean bill of health. Also, when we view them on the PC they display and perform correctly.

 

The affected file types vary sometimes its ".html" files that are corrupted other times its data files needed by the e-commerce processes. Re-sending the files to the server generally solves the problem on the corrupted file, but may simply corrupt something else in the process. It is infuriating that we dont know anything is wrong before a customer finds it out (and usually leaves our shop to go somewhere that doesnt have such troubles).

 

The nature of our e-commerce system is such that it needs to control and perform the file transfers to the server (not all files get uploaded every time, the system controls what needs to be refreshed).

 

I don't want to ask the techs to look for a needle that may not even exist in the haystack, that is why I wondered if there is an FTP log or something I can examine to see if it shows what is going wrong.

 

Thanks,

 

Laura

[TCH-Bruce]

Log into cPanel and select FTP Accounts. At the bottom of the page you will find the FTP logs.

 

How are the files being transferred? With an FTP client? Usually corruption occurs when the file being uploaded is done using the wrong file type. Like a binary file being uploaded in ASCII format or an ASCII file being uploaded in binary. Or it can simply be a bad connection (route losing bits).

[laura_c]

Bruce,

 

Thanks for that. I have seen the list of FTP logs at the bottom of that page, but could not get access to any of them. Perhaps you can tell me how to gain such access? Also the FTP log seems to have 0 size so I'm not sure anything is actually being logged - does something have to be turned on?

 

The FTP mechanism we use is inbuilt to the e-commerce package. This has been running for about 18 months and it is only in the past month that these errors have started to occur. However, nothing has changed in that time (no package upgrade or patch) at the client end that could have caused that - so I'd like to see if there is an error recorded in the logs or if there is potentially a problem at the server end?

 

Thanks,

 

Laura

[TCH-Bruce]

You can get the raw access log for your domain. You may need to open a ticket with the help desk to get the FTP logs.

[laura_c]

Thanks, Bruce.

 

Laura