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now you can acces the website by going to http://localhost:2001/
This will output the sound from your microphone port to the ssh target computer's speaker port. The sound quality is very bad, so you will hear a lot of hissing.
Useful for checking if there are differences between local and remote files.
Unreachable_host is unavailable from local network, but it's available from reachable_host's network. This command creates a connection to unreachable_host through "hidden" connection to reachable_host.
If you use Mac OS X or some other *nix variant that doesn't come with ssh-copy-id, this one-liner will allow you to add your public key to a remote machine so you can subsequently ssh to that machine without a password.
In this case it's better do to use the dedicated tool
Directly attach a remote screen session (saves a useless parent bash process)
Create a persistent SSH connection to the host in the background. Combine this with settings in your ~/.ssh/config:
All the SSH connections to the machine will then go through the persisten SSH socket. This is very useful if you are using SSH to synchronize files (using rsync/sftp/cvs/svn) on a regular basis because it won't create a new socket each time to open an ssh connection.
Of course you need to be able to access host A for this ;-)
Knock on ports to open a port to a service (ssh for example) and knock again to close the port. You have to install knockd.
See example config file below.
logfile = /var/log/knockd.log
sequence = 3000,4000,5000
seq_timeout = 5
command = /sbin/iptables -A INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT
tcpflags = syn
sequence = 5000,4000,3000
seq_timeout = 5
command = /sbin/iptables -D INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT
tcpflags = syn
Shorter, easier to remember version of cmd#7636
NTP is better, but there are situations where it can't be used. In those cases, you can do this to sync the local time to a server.
Much simpler method. More portable version: ssh host -l user "`cat cmd.txt`"
Even faster without the need for cut... :)
Long before tabbed terminals existed, people have been using Gnu screen to open many shells in a single text terminal. Combined with ssh, it gives you the ability to have many open shells with a single remote connection using the above options. If you detach with "Ctrl-a d" or if the ssh session is accidentally terminated, all processes running in your remote shells remain undisturbed, ready for you to reconnect. Other useful screen commands are "Ctrl-a c" (open new shell) and "Ctrl-a a" (alternate between shells). Read this quick reference for more screen commands: http://aperiodic.net/screen/quick_reference
Dumps a MySQL database over a compressed SSH tunnel and uses it as input to mysql - i think that is the fastest and best way to migrate a DB to a new server!
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:
ssh firstname.lastname@example.org tcpdump -w - 'port !22' | wireshark -k -i -
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)
It can resume a failed secure copy ( usefull when you transfer big files like db dumps through vpn ) using rsync.
It requires rsync installed in both hosts.
rsync --partial --progress --rsh=ssh $file_source $user@$host:$destination_file local -> remote
rsync --partial --progress --rsh=ssh $user@$host:$remote_file $destination_file remote -> local
(also works on Ubuntu) Copies the 'install,' 'hold,' 'deinstall' and 'purge' states of packages on the remote machine to be matched on the local machine. Note: if packages were installed on the local machine that were never installed on the remote machine, they will not be deinstalled by this operation.