Tech Monger

In this tutorial we will learn how to use vsftpd on Linux to make Ubuntu machine run as ftp server and transfer files over wifi on local network.

On many occasion you need to copy and backup files locally from one computer to other. Using physical disk like flash drive or external hard drive is not always feasible due to many constraints such large file size, external drive availability.

Setup

We can take advantage of machines being on same network to achieve file transfer.

To follow this guide you should have access to following

• Ubuntu Machine
• Windows Machine
• Both machines connected over same network using ethernet or wifi

How to install VFTP on Ubuntu

Open Terminal to get and install vsftp demon from official ubuntu repository.

sudo apt-get install vsftpd

Above command will install vsftp demon which means it will always be running in background upon machine startup using init.

Use following commands to check vsftp service

sudo service vsftpd status

If service is running then above command will output status of service with all spawned vsftp process ids.

Alternatively you can also check vsftp process with grep

ps -ef | grep vsftp

How to configure VSFTP for Uploads

This step is optional but if you want to allow uploads from remote machine to your ubuntu server then follow below configuration.

After installation vsftp will create configuration file at path /etc/vsftpd.conf. This file should be owned by root and should have default vsftp configuration. By default VSFTP will not allow ftp uploads; to enable it uncomment line write_enable=YES

# Uncomment this to enable any form of FTP write command.
write_enable=YES

Note that /etc/vsftpd.conf would be owned by root, to make any changes in configuration do. sudo vim /etc/vsftpd.conf or sudo gedit /etc/vsftpd.conf

Restart vsftpd demon once configuration is completed.

sudo service vsftpd restart

Check status after restart.

sudo service vsftpd status

How to configure Ubuntu firewall for FTP

By default ubuntu shall be running firewall known as uncomplicated firewall (ufw). Default firewall rules will not allow any outside connection.

To open ftp port on this firewall use following commands.

Check firewall status using

sudo ufw status

Firewall should be active and running. If it's not active then enable the same using following command to make your machine secure.

You can keep it disable if you have such requirement, however it's recommended to keep it on. sudo ufw enable

To open ftp port 21 use following command

sudo ufw allow ftp or sudo ufw allow 21

This will add firewall rule to accept ftp connections from other machine on network. After adding ftp rule you should have following entries in your firewall. sudo ufw status

Status: active
To                         Action      From
--                         ------      ----
21/tcp                     ALLOW       Anywhere                  
21/tcp (v6)                ALLOW       Anywhere (v6)     

Configure Windows Firewall

Firewall should permit you to initiate ftp session from windows machine. Search for Windows Firewall in start menu to open firewall configuration window.

Since we are going to use one time ftp we will disable firewall and reenable it once ftp is done. Depending upon which network you are connected to Home or Public you can disable firewall like below.

Initiate FTP session using Windows command line

Once we are done with required configurations we can initiate first ftp connection from windows command line. First get IP address of machine hosting FTP server using command ifconfig on ubuntu machine. Use eth0 inet address if you are connected with ethernet cable. For wireless connection use inet address of wlan0 interface. My ubuntu machine have following local IP 192.168.2.102.

ifconfig

eth0      Link encap:Ethernet  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

wlan0     Link encap:Ethernet  
          inet addr:192.168.2.102  Bcast:192.168.2.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:24006 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8312 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:12996852 (12.9 MB)  TX bytes:1224374 (1.2 MB)

To initiate connection open command prompt on windows and use following command. ftp 192.168.2.102

It will ask for username and password. Username will be same name as the ubuntu user (techmonger in my case) and password will the ubuntu's system password of user.

To get file from ubuntu ftp server, navigate to directory and use get command like below.

ftp>get filename

To upload file from windows machine to ftp server, put command like below.

ftp>put filename

To terminate ftp session use bye.

ftp>bye

Initiate FTP connection usign ftp client on windows

By now you would agree that doing ftp from windows command prompt is bit tedious. We can use ftp client such as winscp or filezilla to get GUI for ftp operations.

Use hostname as IP address of ftp server (192.168.2.102 in my case) and same credentials as those of ubuntu user.

Like below you can initiate connection from filezilla. You can use drag and drop to download and upload files from windows machine.

FTP Security Aspects - Firewall and Services

All ftp connections will be initiated in plain text. You should only use above method if you are in local network and have complete control over network. For encrypted connections use sftp or ftps.

• Remove firewall rule from ubuntu once ftp requirement is over.

sudo ufw deny ftp or sudo ufw deny 21

• Enable Winows firewall once ftp requirement is over.

• Stop vsftp demon if ftp is no longer needed to save system resources. It will also make your system less vulnerable.

  sudo service vsftpd stop