Too many FTP connection causing Error 421

Solution 1:

If you have access to the FTP server then you can try and force the max number of connections to be unlimited (by default it is limited to 50 connections)

With VSFTPD you add

max_per_ip=0

into the /etc/vsftpd.conf file and restart the service.

However, I am not sure that this will fix your problem. I have had the same issue with oXygen and the only thing that works is usually to kill the tcp connections manually. This gets pretty frustrating but will work:

sudo tcpkill -9 -i <network-interface> host <host-of-your-ftp>

So for example if you had your network interface at eth0 and you were connecting to example.com

sudo tcpkill -9 -i eth0 host example.com

To get a list of your network interfaces you can do

sudo ifconfig

Typically its eth0 for hard wired and wlan0 for wireless bit you should double check.

Hope this helps. If you find another solution to this please let me know.

Cheers,

Casey