Bash command to do multiple things in a server in command line

Question

I am having a problem doing what I need. I can save a ton of time if I do this right.

I basically need to loop over every host, and I can get that part on my own.

But I can never get the command to come out right.

I basically want to do this for every host

 chmod 750 /root; chown -R root:root /root;exit;

I've tried so many variants and all of them them will just ssh to the server and do nothing on that server. They never actually run that command on the destination server. Instead they end up running the command on the server I am running ssh from.

Also note public keys are already set up so passwords are no issue.

So to give a better understanding I will show this

for h in HOSTNAMES do
  ssh $h; OTHER STUFF
done

Are you chaining your "connect to server" command with this using a &? — Rentsy, Dec 16 '15 at 23:00
Have you tried `chmod 750 /root && chown -R root:root /root`? — David Hoelzer, Dec 16 '15 at 23:01
You're not actually showing how you ssh into your servers and execute these commands, though that probably is the problem, here — Marcus Müller, Dec 16 '15 at 23:02
how are you managing entering the password for `root`? I think that has to be the number 1 problem. But we need to see some failed code to help fix it, we can't write it for you ;-) OK? Good luck. — shellter, Dec 16 '15 at 23:03

score 1 · Answer 1 · answered Dec 16 '15 at 23:15

1

this works for me.

C02NQ9GLG3QD:~ lcerezo$ ssh -K myhost "last -1;uptime"
lcerezo   pts/2        172.31.0.40      Wed Dec 16 17:31 - 17:39  (00:07)
wtmp begins Tue Sep  8 17:15:21 2015
16:12  up 1 day,  5:06, 6 users, load averages: 2.16 1.98 2.00
C02NQ9GLG3QD:~ lcerezo$`

Have you looked at tools like pdsh? For mass configuration though, I think your time will be better spent learning a configuration management tool such as:

ansible
puppet
cfengine
salt stack

answered Dec 16 '15 at 23:15

lcerezo

31
3

That might work but not in this instance. I don't have that ability. – Chris Jones Dec 17 '15 at 00:28
Which ability? the -K flag is my usage, but not relevant to the question. the important part is to put these in quotes. – lcerezo Dec 17 '15 at 13:14

miken32 · Accepted Answer · 2015-12-17T03:42:56.343

1

The command to the remote server is given as the final argument to ssh. Also the exit command is not required, as the connection is closed after commands are completed.

for h in $HOSTNAMES
do
  ssh $h "chmod 750 /root; chown -R root:root /root"
done

edited Dec 17 '15 at 03:42

answered Dec 16 '15 at 23:18

miken32

42,008
16
111
154

Yeah I was just wanting to make sure the exit was done... I'll try this when I can later. – Chris Jones Dec 17 '15 at 00:29
This definitely worked. Thanks. I had to modify a few things on my end because of how we can do something but yeah this was great. – Chris Jones Dec 17 '15 at 13:31

Bash command to do multiple things in a server in command line

2 Answers2