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chmod authorized_keys so you don't get "Authentication refused: bad ownership or modes for file /home/user/.ssh/authorized_keys"
You can ran this also with cat for example:
tar zcvf - /folder/ | ssh firstname.lastname@example.org "cat > /dest/folder/file.tar.gz"
Or even run other command's:
tcpdump | ssh email@example.com "cat > /tmp/tcpdump.log"
for passwordless login
Only from a remote machine:
Only access to the server will be logged, but not the command.
The same way, you can run any command without loggin it to history.
ssh user@localhost will be registered in the history as well, and it's not usable.
Sometimes it is necessary to view debug messages to troubleshoot any
SSH connection issues. pass -v (lowercase v) option to the ssh as shown
below to view the ssh debug messages.
Play with the framerate option '-r' to scale back bandwidth usage.
The '-s' option is the captured screan area, not the rescaled size. If you want to rescale add a second '-s' option after '-i :0'. Rescaling smaller will also decrease bandwidth.
More stealthy ffmpeg method. The imagemagick 'import' method causes a system beep.
This command will bypass checking the host key of the target server against the local known_hosts file.
When you SSH to a server whose host key does not match the one stored in your local machine's known_hosts file, you'll get a error like " WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!" that indicates a key mismatch. If you know the key has legitimately changed (like the server was reinstalled), a permanent solution is to remove the stored key for that server in known_hosts.
However, there are some occasions where you may not want to make the permanent change. For example, you've done some port-forwarding trickery with ssh -R or ssh -L, and are doing ssh user@localhost to connect over the port-forwarding to some other machine (not actually your localhost). Since this is usually temporary, you probably don't want to change the known_hosts file. This command is useful for those situations.
Credit: Command found at http://linuxcommando.blogspot.com/2008/10/how-to-disable-ssh-host-key-checking.html. Further discussion of how it works is there also.
Note this is a bit different than command #5307 - with that one you will still be prompted to store the unrecognized key, whereas this one won't prompt you for the key at all.
standard image viewers do not seem to be able to open a FIFO file. xloadimage was the first one i've stumbled upon that can handle this.
You can use sshpass command to provide password for ssh based login. sshpass is a utility designed for running ssh using the mode referred to as "keyboard-interactive" password authentication, but in non-interactive mode.
this command from the source server and this follow in the destination server:
ssh user@localhost -p 8888
You can compare directories on two different remote hosts as well:
diff -y <(ssh user1@host1 find /boot|sort) <(ssh user2@host2 find /boot|sort)
To avoid password-prompt on remote host just generate the rsa key locally and copy it to remote host:
ssh-keygen -t rsa
ssh you@server1 "mkdir .ssh"
scp .ssh/id_rsa.pub you@server1:; .ssh/authorized_keys2
commandline for mac os x
Quick shortcut if you know the hostname and want to save yourself one step for looking up the IP address separately.
remove the host for the .ssh/know_host file
If you have servers on Wide Area Network (WAN), you may experience very long transfer rates due to limited bandwidth and latency.
To speed up you transfers you need to compress the data so you will have less to transfer.
So the solution is to use a compression tools like gzip or bzip or compress before and after the data transfer.
Using ssh "-C" option is not compatible with every ssh version (ssh2 for instance).
This improves on #9892 by compressing the directory on the remote machine so that the amount of data transferred over the network is much smaller. The command uses ssh(1) to get to a remote host, uses tar(1) to archive and compress a remote directory, prints the result to STDOUT, which is written to a local file. In other words, we are archiving and compressing a remote directory to our local box.
The command uses ssh(1) to get to a remote host, uses tar(1) to archive a remote directory, prints the result to STDOUT, which is piped to gzip(1) to compress to a local file. In other words, we are archiving and compressing a remote directory to our local box.
This is also handy for taking a look at resource usage of a remote box.
ssh -t remotebox top