1. Chapter 9 Router Configuration (Ospf, Rip) Webmin, usermin Team viewer
Telnet
SSH
SCP, rsync

2. Router Configuration
Use Cisco Packet Tracer

3. Webmin
Webmin is a web-based interface for system administration for Unix. Using any modern web browser, you can setup user accounts, Apache, DNS, file sharing and much more. Webmin removes the need to manually edit Unix configuration files like /etc/passwd, and lets you manage a system from the console or remotely.
Download webmin.rpm file from google
Install webmin rpm file

4. Webmin
In a web browser, enter the https address of the server with the port number to access Webmin - for example:
-or-
You will need to enter the root password of the server running Webmin to use the Webmin interface and administer the server.

5. Team viewer
TeamViewer is a proprietary computer software package for remote control, desktop sharing, online meetings, web conferencing and file transfer between computers. The software operates with the Microsoft Windows, OS X, Linux, iOS, Android, Windows RT and Windows Phone operating systems. It is possible to access a machine running TeamViewer with a web browser. While the main focus of the application is remote control of computers, collaboration and presentation features are included.

6. What is Telnet?
Telnet is a user command and an underlying TCP/IP protocol for accessing remote computers. Through Telnet, an administrator or another user can access someone else's computer remotely. On the Web, HTTP and FTP protocols allow you to request specific files from remote computers, but not to actually be logged on as a user of that computer. With Telnet, you log on as a regular user with whatever privileges you may have been granted to the specific application and data on that computer.

7. SSH
Secure Shell (SSH) is a cryptographic network protocol for secure data communication, remote command-line login, remote command execution, and other secure network services between two networked computers that connects, via a secure channel over an insecure network, a server and a client (running SSH server and SSH client programs, respectively). The protocol specification distinguishes between two major versions that are referred to as SSH-1 and SSH-2.

8. SCP
Secure copy or SCP is a means of securely transferring computer files between a local host and a remote host or between two remote hosts. It is based on the Secure Shell (SSH) protocol.
scp SourceFile
scp TargetFilescp -r TargetFolder

9. rsync
rsync is a utility software and network protocol for Unix-like systems (with ports to Windows) that synchronizes files and directories from one location to another while minimizing data transfer by using delta encoding when appropriate
One of the earliest applications of rsync was to implement mirroring or backup for multiple Unix clients to a central Unix server using rsync/ssh and standard Unix accounts.

10. The example below is for automatical settings
The example below is for automatical settings. Ecxample ⇒ Copy files and directories in /var/www/html on a HostA[ ] to in /home/backup on HostB[ ].

11. Rsync - Synchronizes files and directories
~]# yum -y install rsync xinetd
~]# vi /etc/xinetd.d/rsync
# default: off # description: The rsync server is a good addition to an ftp server, as it \ #      allows crc checksumming etc. service rsync { disable
= no
# change
flags
= IPv6
socket_type
= stream
wait
= no
user
= root
server
= /usr/bin/rsync
server_args
= --daemon
log_on_failure
+= USERID }

12. [root@dlp ~]# /etc/rc.d/init.d/xinetd start 
Starting xinetd:[ OK ]
~]# chkconfig xinetd on
~]# mkdir /home/backup 
~]# vi /etc/rsyncd.conf
# any name you like
[website] # destination directory
path = /home/backup # Hosts you allow to copy (specify source Host)
hosts allow = hosts deny = * list = true uid = root gid = root read only = false

13. [2]Configure on Source Host.[root@www ~]# yum -y install rsync
~]# vi /etc/rsync_exclude.lst
# specify files or directories you'd like to exclude to copy
test test.txt

14. [3]It's OK. Execute rsync on Source Host like follows.
~]# rsync -avz --delete --exclude-from=/etc/rsync_exclude.lst /var/www/html/ ::website
# Add in cron if you'd like to run reguraly
~]# crontab -e
# run at 2:00 AM in a day * * * rsync -avz --delete --exclude-from=/etc/rsync_exclude.lst /var/www/html/ ::website

15. Packet Analysis by using TCPDUMP and WIRESHARK
TCPDUMP Command
Wireshark installation