Jul 072010
 

If you want to connect to remote machine named othermachine as user named othermachineuser.

On your local machine you need to generate a private-public keypair using ssh-keygen as follows (You only need to do this once):
ssh-keygen -t dsa

This will create a private and public keypair which is stored in ~/.ssh directory.

Next run the following command once for every machine you want to remotely login without specifying password:
scp ~/.ssh/id_dsa.pub othermachineuser@othermachine:~/.ssh/authorized_keys

Now you can login to the machine using ssh without requiring to specify any password. Your public key, which you copied to the remote machine, is checked (not directly) against your private key to verify your authenticity.

Jul 062010
 

On Linux or Unix Systems you can use sftp like this:

sftp -oPort=1234 username@remote.servername.com
After authenticating, the following commands can be used. Any
paths should have quotes if they contain spaces.

Some standard commands and their definitions for command line SFTP include:

?	Get help on the use of SFTP commands.
bye	Close the connection to the remote computer and exit SFTP.
cd	Change the directory on the remote computer.
chgrp	Change the group associated with a computer file (chgrp system foofile).
chmod	Change the permissions of files on the remote computer.
chown	Change the owner of files on the remote computer.
dir	List the files in the current directory on the remote computer.
exit	Close the connection to the remote computer and exit SFTP.
get	Copy a file from the remote computer to the local computer.
help	Get help on the use of SFTP commands.
lcd	Change the directory on the local computer.
lls	See a list of the files in the current directory on the local computer.
lmkdir	Create a directory on the local computer.
ln	Create a symbolic link for a file on the remote computer.
lpwd	Show the current directory (present working directory) on local computer.
ls	Show the current directory on the remote computer.
lumask	Change the local umask value.
mkdir	Create a directory on the remote computer.
progress Toggle display of progress meter.
put	Copy a file from the local computer to the remote computer.
pwd	Show the current directory (present working directory) on remote computer.
quit	Close the connection to the remote computer and exit SFTP.
rename	Rename a file on the remote host.
rm	Delete files from the remote computer.
rmdir	Remove a directory on the remote host (the directory has to be empty).
symlink	Create a symbolic link for a file on the remote computer.
version	Display the SFTP version.
! 	In Unix, exit to the shell prompt, where you can enter commands. Enter exit
	to get back to SFTP. If you follow  !  with a command (e.g., !pwd), SFTP
	will execute the command without dropping you to the Unix prompt.
Jan 262010
 

SSH – Secure Shell

Creating an SSH Tunnel to my router at home.
ssh -N -L 8888:1.2.3.4:80 username@computername.domainname.com
Open up a web browser on your local pc and type in http://localhost:8888 and you will
be redirected to your home router on port 80.

If you want to tunnel X through SSH type: ssh -X username@servername.
Once you log in you can type the name of a GUI program (firefox) and it will render in a window on your local machine.
-X allows X forwarding.  -x can be used to disable X11 forwarding

Use XMing to display X on Windows Xming X Server for Windows SFXPutty-XMing.Screenshots.

Using X Forwarding on Windows HowTo.

My SSH Settings

Jan 152010
 

From here to there:
scp filename userid@hostname:filename
scp filename userid@hostname:/path/to/filename

From there to here:
scp 192.168.1.100:*.txt .
scp userid@hostname:*.txt .
scp userid@hostname:/path/to/filename

Directories from here to there:
scp -r directoryname userid@hostname:directoryname2

Directories from there to here:
scp -r userid@hostname:directoryname2 .