Block FTP access using the CSF firewall
1) If you want to completely disable the FTP access on the server then follow the steps :
root@server
Search for the lines :
# Allow incoming TCP ports
TCP_IN =
and remove the port 21 from the list
Save and quit .
And then restart the CSF firewall using the below command :
root@server
2) If you want to block FTP access for a Specific IP then follow the below steps :
root@server
and add the line :
tcp:in:d=21:s=10.10.10.10
save and quit
And then restart CSF firewall using the below command :
root@server
3) If you want to allow FTP access for only one ip on the server and denied for all other ips
follow the steps :
root@server
Then search for the line :
# Allow incoming TCP ports
and the remove the ports : 21 and 22
and also search for the line :
# Allow outgoing TCP ports
and remove the ports : 21 and 22
Save and quit
Then open the csf.allow file
root@server
and add the entry as :
tcp:in:d=21:s=10.10.10.10
Save and Quit.
And then restart the CSF service
root@server
Note : Replace the IP 10.10.10.10 with the Actual IP.