upload a file and then ftp it to another server with PHP

I generated a text file on server1, and then I need to FTP it开发者_如何转开发 to server3.

Due to firewall, I could not FTP it directly but have to go through server2.

I want server1 to call PHP script on server2 and then pass the text file to server3. Any idea how can I start with the PHP script?

Perhaps curl is going to help. Use curl to call the script on server 2. Then, form server2 you can ftp to server3. curl supports post-ing a lot data, so you should be fine. Not sure if it's the best solution, but it might get the job done.