i have followed this tutorial to set up Mail server in existing Web server droplet.

everything went well, but VSFTP stopped working

i tried this command to see the ports

sudo netstat -ntlp | grep LISTEN

and VSFTP is listening on

tcp     0    0 0.0.0.0:21    0.0.0.0:*    LISTEN   17250/vsftpd

i can able to access it from my local machine but its not working from external machines.

i used to access it like ftp://mydomain.com
but its not working now. how can i fix this?

I changed my hostname recently, is it going to affect any on VSFTP?