On 16Oct2018 14:14, tina_zy_q...@yahoo.com <tina_zy_q...@yahoo.com> wrote:
I newly learned Python, and I need to wrap up a script to do following.Env: 1: One launcher Linux VM (from where to run the Python script) 2. 100+ Linux VM requirement: In general, run a remote_script on remote 100 VMs and get the log files generated to remote hosts back to launcher. steps 1. cp (pexpect.spawn('scp ')) supporting files including the remote_script to remotehost:/remote_folder 2. run remote_script on remote host ( pexpect.spawn('ssh %s@%s "%s"' % (user,host,cmd)) 3. wait and check until the remote_script was run on remote host. (to check "ps -ef" result on remote hosts) 4. collect data from remote hosts -- reverse to step 1. I briefly implemented other steps expect step 3. Two options are below. option 1: run another script "ps -ef|grep remote_script and output result to a local file, then collected the files to launcher. option 2: run pexect.spawn('ssh' ....'ps -e') to get the result directly to laucher console. But how I can get only the output for "ps -ef" command only?I must use the (users, passwords, and hosts) way to do ssh and scp because I may not be allowed to use ssh key on some hosts. Any suggestions or sample code for step 3 or the whole script are appreciated. Thanks.
Have you looked at ansible? It is a Python/ssh library/tool for remote admin. It is almost designed for this kind of thing. Run local script on remote hosts in parallel and wait for them? Tick.
Ansible can prompt (once) for a remote ssh password and apply it to all the remote ssh invocations.
I _strongly_ recommend you do this with keys though. Passwords are something of a security nightmare.
You can be sure that the remote script has run if the ssh which invoked it returned with a zero exit status. If the ssh itself aborts, or the script fails, you get a nonzero status back from ssh.
Personally I would be (a) trying to do this without passwords - install keys and (b) using threads to spawn all the remote sshes, have each thread wait for its own ssh, and wait for all the threads.
Or reaching for ansible, which has this kind of logic built in. Cheers, Cameron Simpson <c...@cskk.id.au> -- https://mail.python.org/mailman/listinfo/python-list
