中止shell脚本会中止正在执行的命令

Question

I am a noob to shell scripting, I tried searching but could not find a solution.

I have a bad internet connection and it keeps dropping. I have to run certain commands on a remote server. When I ssh on a terminal and run those commands and the connection drops, I'm not sure if the command continues or it also stops (I assume that it would behave as if a Ctrl^C has been received. Am I correct?)

Now i've put all the commands inside a shell script. ftp-ed it on the server and am running it on a terminal via ssh. Will this guarantee that my commands would run even if the connection gets dropped. Or should I wrap it inside another shell script?

Thank you.

Answer 1

If you need to preserve the command that is run remotely after the connection drops use nohup . For details see man nohup . I guess all you need to do is to run on remote side:

nohup /path/to/your_script.sh &

More precisely, whenever the connection is dropped, on the server side timeout occurs, the socket is closed and with it all the processes that belong to the process tree of the ssh connection process.

Answer 2

Do you need to see the output?

If so, then use screen , which effectively runs everything on the server and lets you connect to the screen remotely.

If you don't, then you can use nohup to background the process. When doing so, make sure you redirect the standard streams ie

nohup script_to_run &>/dev/null </dev/null &

Answer 3

在screen会话中使用nohup运行脚本或运行脚本

Answer 4

To guarantee a command or script will run even if connection is dropped, use nohup .

For even more control, use GNU Screen (you will be able to reconnect and get back to the terminal of the running command).

man nohup and man screen have more info.