Commands tagged ssh

the command is obvious, I know, but maybe not everyone knows that using the parameter "-l" you can limit the use of bandwidth command scp.

In this example fetch all files from the directory zutaniddu and I copy them locally using only 10 Kbs

You set the file/dirname transfer variable, in the end point you set the path destination, this command uses pipe view to show progress, compress the file outut and takes account to change the ssh cipher. Support dirnames with spaces.

Merged ideas and comments by http://www.commandlinefu.com/commands/view/4379/copy-working-directory-and-compress-it-on-the-fly-while-showing-progress and http://www.commandlinefu.com/commands/view/3177/move-a-lot-of-files-over-ssh

connects to host via ssh and displays the live transfer speed, directing all transferred data to /dev/null

needs pv installed

Debian: 'apt-get install pv'

Fedora: 'yum install pv' (may need the 'extras' repository enabled)

Please check out my blog article on this for more detail. http://jdubb.net/blog/2009/08/07/monitor-wireshark-capture-real-time-on-remote-host-via-ssh/

This allows you to display the wireshark program running on remote pc to your local pc.

connects to host via ssh and displays the live transfer speed, directing all transferred data to /dev/null

needs pv installed

Debian: 'apt-get install pv'

Fedora: 'yum install pv' (may need the 'extras' repository enabled)

This captures traffic on a remote machine with tshark, sends the raw pcap data over the ssh link, and displays it in wireshark. Hitting ctrl+C will stop the capture and unfortunately close your wireshark window. This can be worked-around by passing -c # to tshark to only capture a certain # of packets, or redirecting the data through a named pipe rather than piping directly from ssh to wireshark. I recommend filtering as much as you can in the tshark command to conserve bandwidth. tshark can be replaced with tcpdump thusly:

We force IPv4, compress the stream, specify the cypher stream to be Blowfish. I suppose you could use aes256-ctr as well for cypher spec. I'm of course leaving out things like master control sessions and such as that may not be available on your shell although that would speed things up as well.

download the denyhosts-remove script from http://www.atrixnet.com/remove-an-ip-address-ban-that-has-been-errantly-blacklisted-by-denyhosts/

This command will copy a folder tree (keeping the parent folders) through ssh. It will:

- compress the data

- stream the compressed data through ssh

- decompress the data on the local folder

This command will take no additional space on the host machine (no need to create compressed tar files, transfer it and then delete it on the host).

There is some situations (like mirroring a remote machine) where you simply cant wait for a huge time taking scp command or cant compress the data to a tarball on the host because of file system space limitation, so this command can do the job quite well.

This command performs very well mainly when a lot of data is involved in the process. If you copying a low amount of data, use scp instead (easier to type)

Get your server's fingerprints to give to users to verify when they ssh in. Publickey locations may vary by distro. Fingerprints should be provided out-of-band.

You can use this to directly dump from machine A (with dvd drive) to machine B (without dvd drive) . I used this to copy dvd using my friend's machine to my netbook. Above command is to be issued on machine B.

Advantages :

1) No wasting time dumping first to machine A and then copying to Machine B.

2) You dont need to use space on Machine A. In fact, this will work even when Machine A doesnt have enough hdd space to dump the DVD.

Use -C ssh option on slow networks (enables compression).

you can replace "dd if=/dev/dvd" with any ripping command as long as it spews the iso to stdout.

This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed.

dsh - Distributed shell, or dancer?s shell ;-)

you can put your servers into /etc/dsh/machines.list than you don't have to serperate them by commata or group them in different files and only run commands for this groups

dsh -M -c -a -- "apt-get update"

Once it is connected to the remote server by that ssh protocol,the mentioned command will start working on that server.

Stop tormenting the poor animal cat!

Also you should not that you need a private key not protected by a passphrase on middlehost that grants you access to securehost..

If you need to ssh into a computer on the local network but you're unsure of the ip to use, then ping them and see if you get a response. If you do, print out the address you got it from. Adjust the range to suit your network.

copy files to a ssh server with gzip compression

middlehost allows ssh access from where you are but not securehost.

Use nice ssh piping to simulate scp through A => B => C

setting up the shell function if left as an exercise for the reader. ;-)

Agent forwarding should avoid password typing.

Useful to move many files (thousands or millions files) over ssh. Faster than scp because this way you save a lot of tcp connection establishments (syn/ack packets).

If using a fast lan (I have just tested gigabyte ethernet) it is faster to not compress the data so the command would be:

tar -cf - /home/user/test | ssh user@sshServer 'cd /tmp; tar xf -'

This starts a very basic X session, with just a simple xterm. You can use this xterm to launch your preferred distant session.

Try also startkde or fluxbox or xfce4-session.

To switch between your two X servers, use CTRL+ALT+F7 and CTRL+ALT+F8.

Directly attach a remote screen session (saves a useless parent bash process)

Redirects the contents of your clipboard through a pipe, to a remote machine via SSH.