I am connecting to a remote host via ssh login and running logstash by the following command
$./logstash -f first-pipeline.conf
However, after I logout from the server, the logstash stops running. How to enable it to keep running even after I logout. Thanks.
Another approach is to use the screen command which can be very useful for this.
First you open your SSH session, then type screen at the prompt. That opens a new session in which you can run your logstash command.
When it runs, you simply press Ctrl+a d in order to detach your self from that screen and you can safely logout.
Whenever you log back into your SSH session, you enter screen -r and you will get back into your previous session where logstash was started.
You can create as many "screens" as you wish to start many different processes at different times.
Also see this comparison between using nohup and screen
Just run it as an agent
$ logstash agent -f ~/logstash/pipeline.conf
Related
I have a bash script that I have to regularly run on a remote server. Part of the script includes running a backup which takes a while, and after it has run, I have to hit "Y" to confirm that the backup worked before the script will continue.
I would like to know if there is a way to get my laptop to make a beep (or some sort of sound) when that happens. I know that echo -e '\a' makes a beep, but if I run it from within a script on the remote server, the beep happens on the remote server.
I have control of the script that is being run, so I could easily change it to do something special.
You could send the command through ssh back to your computer like:
ssh user#host "echo -e '\a'"
Just make sure you have ssh key authentication from your server to your computer so the command can run smoothly
In my case the offered solutions with echo didn't work. I'm using a macbook and connect to an ubuntu system. I keep the terminal open and I'd like to be informed when a long running bash script is ready.
What I did notice is that if I shutdown the remote system then it will beep the macbook and show an alarm icon on the relevant tab. So I have now implemented a bit of dirty workaround:
sudo shutdown 1440 && shutdown -c
This will initiate the system to shutdown and will immediately cancel the request. And I do get the alarm beep + icon. You will need to setup sudo to allow the user to permit shutdown. As it was my own remote server it was no problem but could limit the usability for others.
What's the best way to run this shell script where I need to create an output log at the same time run it in the background? The catch is, I need to input a couple of parameters then enter a password.
For example I execute the shell script like so:
-bash-4.3$ ./tst.sh param1 param2 >> tst.log
Password for user mas:
I need to pass in (2) parameters, then prompted for a password:
./tsh.sh <param1> <param2>
This will work, but I have to keep the session open and I want it so it goes to the background or something similar where it will continue to run if my connection to the host fails..
If you want to run something that will survive if your connection fails you should run it in a screen or tmux session. You can use those to create sessions that you can disconnect from and reconnect to, and many other really cool things once you start really getting into them.
So if you ssh in and then run screen you'll still be at a bash prompt, but if you run a command then press ^a^d you will detach from that session. Everything running inside screen will keep going, and you'll be able to reconnect with screen -x later. You can have many screen sessions at the same time too, use screen -ls to see which are running then you can use screen -x <id> to reconnect to a particular one.
I need to open an ssh connection on login and keep it open, but to not acutally do anything with it. It would be best if all of it would run in the background.
I created an automator application and made it run a shell script on the bash. The script looks as follows:
sshpass -p 123456 ssh 123456#123.123.123.123
If i try to run the application i keep getting an error message, however if i execute the exact same script in an terminal it works just fine.
Is there any way i can open that connection with an automator application and keep in the background?
You can send a KeepAlive packet to stop the pipe from closing.
In your ~/.ssh/config, and the following:
Host *
ServerAliveInterval 300
ServerAliveCountMax 2
What this says is that that every 300 seconds, send a null (keep-alive) packet and give up after 2 tries.
Source: http://patrickmylund.com/blog/how-to-keep-alive-ssh-sessions/
Do you really need to involve Automator at all?
Just save the script (say, foo.sh) in a folder with the same name as the script (i.e. foo.sh as well).
Put this folder in /System/Library/StartupItems/ and it will run when you start up your machine.
I'm opening an ssh-session to a remote server and execute a larger (around 1000 lines) bash-script on the remote machine. It involves several very CPU-intensive calls which run for up to three minutes each. To track the scripts progress it echoes messages placed at several points in the script.
In general the script runs smoothly. From time to time the script runs trough (the resulting file on the remote machine is correct) but the output to the terminal stops. Ctrl-C doesn't help, no prompt, just a frozen session. top in a separate session shows normal execution of the script.
My question: How keep the session alive?
local machine:
$ sw_vers
ProductName: Mac OS X
ProductVersion: 10.9
BuildVersion: 13A603
remote machine:
$ lsb_release -d
Description: Ubuntu 12.04.3 LTS
Personally, I would recommend using screen or tmux on the remote terminal for exactly this reason.
Those apps will allow the remote process to continue even if your local SSH session times out.
http://www.bangmoney.org/presentations/screen.html
http://tmux.sourceforge.net/
Start a screen on the remote machine and run your command from it:
screen -S largeScript
And then
./yourLargeScript.sh
Whenever your ssh session gets frozen, you can kill it with ~.
If you ssh again, you can grab back your screen by:
screen -dr largeScript
Make it log to a file instead (perhaps via syslog), and tail that file from wherever is convenient for you. This also helps detach the script so you can run it headless, from a cron job, etc. Also, if the log file has read access for others, they too can monitor it.
This hopefully should be an easy question to answer. I am attempting to have mumble-ruby run automatically I have everything up and running except after running this simple script it runs but ends. In short:
Running this from terminal I get "Press enter to terminate script" and it works.
Running this via a cronjob runs the script but ends it and runs cli.disconnect (I assume).
I want the below script to run automatically via a cronjob at a specified time and not end until the server shuts down.
#!/usr/bin/env ruby
require 'mumble-ruby'
cli = Mumble::Client.new('IP Address', Port, 'MusicBot', 'Password')
cli.connect
sleep(1)
cli.join_channel(5)
stream = cli.stream_raw_audio('/tmp/mumble.fifo')
stream.volume = 2.7
print 'Press enter to terminate script';
gets
cli.disconnect
Assuming you are on a Unix/Linux system, you can run it in a screen session. (This is a Unix command, not a scripting function.)
If you don't know what screen is, it's basically a "detachable" terminal session. You can open a screen session, run this script, and then detach from that screen session. That detached session will stay alive even after you log off, leaving your script running. (You can re-attach to that screen session later if you want to shut it down manually.)
screen is pretty neat, and every developer on Unix/Linux should be aware of it.
How to do this without reading any docs:
open a terminal session on the server that will run the script
run screen - you will now be in a new shell prompt in a new screen session
run your script
type ctrl-a then d (without ctrl; the "d" is for "detach") to detach from the screen (but still leave it running)
Now you're back in your first shell. Your script is still alive in your screen session. You can disconnect and the screen session will keep on trucking.
Do you want to get back into that screen and shut the app down manually? Easy! Run screen -r (for "reattach"). To kill the screen session, just reattach and exit the shell.
You can have multiple screen sessions running concurrently, too. (If there is more than one screen running, you'll need to provide an argument to screen -r.)
Check out some screen docs!
Here's a screen howto. Search "gnu screen howto" for many more.
Lots of ways to skin this cat... :)
My thought was to take your script (call it foo) and remove the last 3 lines. In your /etc/rc.d/rc.local file (NOTE: this applies to Ubuntu and Fedora, not sure what you're running - but it has something similar) you'd add nohup /path_to_foo/foo 2>&1 > /dev/null& to the end of the file so that it runs in the background. You can also run that command right at a terminal if you just want to run it and have it running. You have to make sure that foo is made executable with chmod +x /path_to_foo/foo.
Use an infinite loop. Try:
while running do
sleep(3600)
end
You can use exit to terminate when you need to. This will run the loop once an hour so it doesnt eat up processing time. An infinite loop before your disconnect method will prevent it from being called until the server shuts down.