Multiple Commands from One Command Line

ntbluez · 11-06-2015, 08:36 PM

Hi.
I want to run two commands from terminal and write the results to a file.
I want the output file to contain a listing of the hostname and directory .xyz if it exists on that server.

I've created a server-list file which contains 100 servers.
so, I attempted to do this, but cannot get the hostname from each server to write to the file, but the ls -a command does appear in the file.

ssh Tom@192.168.1.5 ls -a | grep .xyz; hostname

Any input is appreciated!
ntbluez

berndbausch · 11-06-2015, 09:06 PM

Your errors are:

you run hostname on your local system
rather than listing the content of .xyz, you list the content of Tom's home directory
you don't look for a directory named .xyz. The dot has a special meaning for grep, namely "any character". So, you look for a file whose name has at least four characters and includes "xyz"

Something like this might be your solution:

Code:

ssh Tom@192.168.1.5 sh -c "ls -a .xyz 2>/dev/null || hostname"

This runs a shell on the remote system and asks that shell to

execute the ls
discard any error messages from the ls command
run hostname only if the ls command succeeds

If you want the hostname to be printed even if there is no .xyz directory, replace the double pipe by a semicolon.

Sefyir · 11-06-2015, 09:07 PM

Place it in single quotes?

Code:

ssh Tom@192.168.1.5 'ls -a | grep \.xyz; hostname'

Do you want the contents of .xyz listed or just the fact that it exists?
Also, this will be run from the home directory of "Tom" - e.g. /home/tom/

ntbluez · 11-07-2015, 07:48 AM

Thanks!
Yes. I want to know if the directory exists, not necessarily if there are files inside the directory.
Appreciate the feedback

Turbocapitalist · 11-07-2015, 09:15 AM

Quote:

Originally Posted by ntbluez

Yes. I want to know if the directory exists, not necessarily if there are files inside the directory.

Then you might want "test" instead of "ls"

Code:

test -d ./xyz/ && echo There || echo Not There

MadeInGermany · 11-07-2015, 09:45 AM

Quote:

Originally Posted by Sefyir

Place it in single quotes?

Code:

ssh Tom@192.168.1.5 'ls -a | grep \.xyz; hostname'

Is that sufficient? The local shell evaluates and strips off the ticks; th remote shell gets

Code:

ls -a |grep \.xyz; hostname

and strips off the backslash. The grep gets

Code:

.xyz

and that also matches

Code:

axyz

. And there is no anchor so it will even match

Code:

helloxyz

and

Code:

helloxyzhello

.
The previous solution is precise. Or

Code:

ssh Tom@192.168.1.5 'ls -d .xyz; hostname'

berndbausch · 11-07-2015, 06:55 PM

It's hard to manage all the backslashes and other quoting mechanisms when nesting command lines like this. MadeinGermany has got it right I think. A test or an ls are simpler solutions.

ntbluez · 11-10-2015, 06:29 PM

I appreciate the feedback and hints you've provided! I noticed the output lists the information on two separate lines. What if I want the output to list the computer name and directory name or if it exists on one line? What would the command be to achieve this? Thanks again!

berndbausch · 11-10-2015, 10:51 PM

Quote:

Originally Posted by ntbluez

I appreciate the feedback and hints you've provided! I noticed the output lists the information on two separate lines. What if I want the output to list the computer name and directory name or if it exists on one line? What would the command be to achieve this? Thanks again!

Without knowing the command you are entering, it's kind of difficult to answer your question.