Permission denied in FTP even though I'm the owner

After you install the ftp server with sudo apt-get install vsftpd you will have to configure it. To enable write access you have to edit the /etc/vsftpd.conf file and uncomment the

#write_enable=YES

line, so it should read

write_enable=YES

Save the file and restart vsftpd with sudo service vsftpd restart.

For other configuration options consult this documentation or man vsftpd.conf

A simple way I found to use ftp with curl command here. If you wanna use ftp with a single command than use the following command

sudo curl -T file_to_be_uploaded.txt ftp://mydomain.com/mydirectory/ --user username:password

If you get an error 551: permission denied than run it the file you are uploading might be present on the remote and you don't have permission to overwrite it. So upload it with a different file name or delete the current file on the remote.