About once a week, a ticket works its way down the grapevine. User cannot upload a file by FTP. It’s always a different user, but the problem is the same. I don’t think it’s the frequency of the problem that’s frustrating, it’s tracking the source of the problem.
What are their firewall settings? What are our firewall settings? Are they coming across the VPN? Is it an active or passive data connection? Is their FTP script sending the wrong password again? Are they hitting the proftpd server or the wu-ftpd server? Hey, this FTP daemon log doesn’t report any connection details!
In the end, there’s always a different root cause. Maybe it’s a NAT translation failure, or a load balancer that needs to be rebooted. Next week it will be a totally different scenario, and a totally different solution.
FTP is an antiquated protocol, designed to address early shortcomings in the IP protocol over 25 years ago. In my humble opinion, it’s time to give up and let this protocol die. There are other protocols out there that can do the job just as well, if not better. Here are the top contenders:
SCP/SSH. Secure authentication, and data encryption to boot. SCP is available on almost every platform out there. There are even a few decent SCP GUI clients out there. The only downside is there aren’t too many tools that can script SCP uploads on a Windows host.
SVN/CVS/Other. Okay, these protocols are a little restrictive. They allow for file uploads and downloads, but their main function is versioning control. Neither of them will be helpful if you’re trying to perform simple file transfer operations outside of a centralized repository.
Jabber. Not a popular protocol, but something to keep in mind. It would be incredibly easy to set up peer to peer file exchanges between client/servers or client/client environments.
HTTP. This should be the obvious choice; I know it’s my personal favorite. HTTP has authentication mechanisms built into the protocol, SSL is available, download recovery is possible, and servers can design fancy HTML interfaces for uploads and downloads through a web page. Plus, almost every programming and scripting language out there has a HTTP client library to facilitate scripted actions.
Probably the only thing that doesn’t work well is HTTP upload through a web browser. They will upload files, but web clients like Firefox (and others) don’t bother to report upload statistics like bytes sent or time remaining. Anyone uploading files a file is stuck in feedback limbo. Is my file being sent? The blue E is just spinning.
If somebody out there develops an extension or program to make HTTP uploads easier, they will have my immediate gratitude. I’ll email the program’s webpage to every remote user I have, with a side note saying that they will no longer need to send me their entire firewall configuration to debug problems in the future.