FTP servers port no : 20/21

FTP servers port no : 20/21

the file transfer protocal (ftp) is used as one of the most common means of copying files between servers over the internet. Most of web based download sites use the built in FTP capabilites of web browsers.

Main function of ftp servers id download and upload files.

port no : 20 data send
21 connection create

2 types of servers

1> local user having password : eg. alex with home directoy /home/alex

2> anonymous user not have any password and direcotry is /var/ftp

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Required package : vsftpd ( very secure FTP )
conf dir : /etc/vsftpd
Home dir : /var/ftp
log : /var/log/xferlog
conif : /etc/vsftpd/vsftpd.conf
other : /etc/vsftpd/user_list
/etc/vsftpd/ftpusers

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configure FTP server :

1> #yum install vsftpd

2> #vim /etc/vsftpd/vsftpd.conf
By default it provide download permisson and login permission to all limited and anonymous users

anonymous_enable = Yes [ allow anonymous FTP ]

local_enable = Yes [ allow limited users ]

write_enable = Yes [ allow write /upload permission ]

anon_upload_enable = Yes [ enable anonymous upload By default off ]

anon_mkdir_write_enable = Yes [ anonymous user create directory by default off ]

dirmessage_enable = Yes

[ it shows message once enter in pub directory. create “.message” file and put your message. create this file in pub directory ]

ftpd_banner = “welcome ” [ show msg on login ]

:wq

3> #service vsftpd restart

4> #chkconfig vsftpd on

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Client side

1> graphical access

ftp://192.168.122.10

2> command line access

#yum install ftp

#ftp 192.168.122.10
enter user name : ftp   [ anonymous user ]
enter password :       [ no password for anonymous user ]

ftp > ?   ——-go to help
ftp > exit ——-quit
ftp > cd download
ftp > get nasa.txt —————–download file
ftp> mget file1 file2 file3 ——–download multiple files
ftp> mget * ————————download all files
ftp> put file1.txt ————–upload file
ftp> mput file1 file2 ————upload multiple files

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Extra :

1>> selinux permission restrict while uploading file
#sestatus

#setenforce 0

#getsebool -a | grep ftp [collect ftp boolean ]

#setsebool -P allow_ftpd_anon_write on

#setsebool -P ftp_home_dir on

Now try to upload file

upload using ftp affected by following SEsecurity
1> file base permission
2> SELinux

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2>> create chroot environment

1> #vim /etc/vsftpd/vsftpd.conf

chroot_local_user = YES
Or
List particular users

chroot_list_enable = YES
chroot_list_file = /etc/vsftpd/chroot_list

:wq

2> #vim /etc/vsftpd/chroot_list
alex

:wq

3> #service vsftpd restart

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3>> advance options

Need to add these line manually in conf file

I > restrict FTP service to particular interface

listen_address = 192.168.0.10

II> hide gid/uids
hide_ids = YES

III> Disable dowload permission
download_enable = no

IV> define download speed
anon_max_rate = 1656116 [ byte ]
loacl_max_rate = 10000 [ byte ]

V> maxinum connection
max_clients = 1

VI> maximum connection per IP
max_per_ip = 1

VII> banner file
banner_file = /etc/vsftpd/ftp

[ you can ref manual for more option
#man vsftpd.conf

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