Ubuntu Linux Set Iscsi Initiator

Posted on in Categories last updated July 2, 2010

ISCSI is a network protocol standard that allows the use of the SCSI protocol over TCP/IP networks. How do I setup Iscsi Initiator under Ubuntu Linux? How do I format and connect to an iSCSI volume under Ubuntu Linux? How do I store VMware or Virtualbox virtual machine images using iscsi storage?

How to Tunnel X Windows Securely over SSH

Posted on in Categories , , , , , , , , , , , , , , , last updated November 20, 2007

Q. How do I tunnel X Windows Securely over SSH? I’d like to run X program on my remote Linux server and get back display to Laptop computer connected by high speed internet?

A. A tunneling protocol is a network protocol which encapsulates a payload protocol, acting as a payload protocol. Reasons to tunnel include carrying a payload over an incompatible delivery network, or to provide a secure path through an untrusted network.

SSH is frequently used to tunnel insecure traffic over the Internet in a secure way. Simply type the following command:

$ ssh -X [email protected]
$ ssh -X [email protected]

You can requests compression of all data to improve up user experience (good for a low speed link such as wan link) using -c option:
$ ssh -c -X [email protected]

Once logged in type any X windows program name such as:
$ xeys &
$ oowriter &

To start kde type:
$ startkde &

To start default desktop type:
$ startx

How do I turn on telnet service on for a Linux / FreeBSD system?

Posted on in Categories , , , , , , last updated December 28, 2007

Q. Can you example how can I install telnet service or server under Linux or FreeBSD operating system?

A. TELNET (TELetype NETwork) is a network protocol used on the Internet or local area network LAN connections.

The telnetd program (telnet server) is a server which supports the DARPA telnet interactive communication protocol. Telnetd is normally invoked by the internet server inetd or xinetd for requests to connect to the telnet port as indicated by the /etc/services file. Usaually telnet listen on port TCP port 23.

Telnet in is insecure protocol and it is recommended that you use ssh server. But some time you really need telnet then first install telnet server as according to version of Linux distribution.

Telnet server installation

WARNING! Installing telnet open your computer to unencrypted network communication, which is a bad idea. If possible avoid telnet; and use secure shell called ssh.

Debain/Ubuntu Linux user type the following command:
# apt-get install telnetd
$ sudo apt-get install telnetdFedora Linux user the following command:
# yum install telnet-server telnetRed Hat enterprise Linux user type the following command:
up2date telnet-server telnetFreeBSD user type the following command:
No need to install new (telnet server) package, it is installed by default (/usr/libexec/telnetd)

Configure telnet server (turn on telnet server)

Again each distribution has its own method to turn on or off telnet service; same applies to telnet UNIX/Linux server.

If you are using Red Hat / Fedora Linux
The configuration file for telnet is /etc/xinetd.d/telnet. To enable telnet server you need to open this file and make sure disable = no read as disable = yes.
# chkconfig telnet onTo start telnet server type command:
# /etc/init.d/xinetd restartIf you are using Debian Linux
The configuration file for telnet is /etc/inetd.conf. By default it is enabled when you install telnet server. To start telnet server type command:
# /etc/init.d/inetd restartIf you are using FreeBSD
The configuration file for telnet is /etc/inetd.conf. Open file using vi text editor and uncomment line:
# vi /etc/inetd.conf
Make sure commented line:
#telnet stream tcp nowait root /usr/libexec/telnetd telnetdRead as follows:
telnet stream tcp nowait root /usr/libexec/telnetd telnetdSave and close the file. Start telnet service:

Enable inetd service so that telnet get loaded:
# vi /etc/rc.confAppend/add following line to configuration file:
inetd_enable="YES"Save and close the file, Rsstart telnet via inetd service:
# /etc/rc.d/inetd restart

Telnet to server (How do I use telnet client?)

You should now be able to telnet to the server from Windows or Linux desktop system. Type the following command to connect to Telnet server:telnet server-ip-address