Remote Login

Remote Login

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1> Linux to Linux

Shell access : SSH (secure socket) – encrypted way
port no : 22

SSH support both SSL and TLS. In the previous technology it uses protocol telnet

Old technology : telnet and rlogin ( text base) non secure

Kerberos used with telnet for rlogin to secure the authetication.

#ssh IP_address

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During remote connection they share public key during first connection attempt then ask for username and password
It store “/etc/ssh/ssh_host_rsa_key.pub” of remote machine to know host file at /root/.ssh/known_hosts

/root/.ssh
i. known_hosts
ii. id_rsa
iii. id_rsa.pub

symmetric Key => single key used for encryption and decrytion.
Assymetric kye => public key used for encryption and private key for decryption. Public key pass to other end and share in know_host file. This kind of technology help to prevent man_in_middle attack.

SSH confiugration file
/etc/ssh/sshd_config
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Graphical Access

VNC : virtual Network computing
Port no : 5900/5901
Pakage : It require vnc on source machine. It comes with RHEL DVD

Add package
System => administration => add/remove S/W => search tiverVNC => install

OPen require software
Application => internet => Tiger VNC viewer => enter remote IP and details
OR
#vncviewer 192.168.0.2

Note :
While getting remote access it is mandetory that remote machine should have access allow

System => preferences => Remote desktop

-Here are different option. e.g require password authentication, control etc.
-When remote connectiobn establish it show incomming connection message on remote system. When remote operator will accept it then only autual connection done
-it gives connection with current login user to remote machine.

Disconnect the remote connection :
-it generate icon at top panel when connection establish.
-right click on that icon.
-disconnect server name
-disconnect

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2> Linux to windows
RDP ( remote Desktop Protocol)
port : 3389
Package : rdesktop

Linux has “rdesktop” untility. It is a client for remote desktop protocol ( RDP) used in number of microsoft operation system. eg. NP, vista, windows7 etc.

It do not have graphical interface. You need to execute “rdesktop” command.

Add/remove S/w => search for rdesktop => install.

#rdesktop -a 13 192.168.122.248   ———– 13(resolution)

extra :
#firstboot => this command give first boot window same comes after installtion complete to set date/time, add root user etc.

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3> Windows to Linux
It require some third party application to access linux. Because windows do not have built in s/w for this.

i. Putty : command line access
ii. vncviewer : graphical

windows provide one user login at a time hence when we access windows machine remotely it disconnect remote operator access. ( ie. at destination machine.)
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Posted in Fundamental

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