How to use bash $(awk) in single ssh-command?

Question

I am trying to execute a single command over ssh that contains `sub-code` or $(sub-code) (I use it all the time but I don\'t know the official name for that) to

Answer 1

What about piping the output of the command and run awk locally?

ssh yourhost uname -a | awk '{ print $2 } '

Answer 2

The workaround is to create an sh file with the command then pass it to ssh command:

test.sh

echo `uname -a | awk '{print $2}'`

and command:

ssh myServer 'bash -s' < test.sh

UPDATE:

The command without quotes works fine as well:

ssh myServer uname -a | awk '{print $2}'

Answer 3

If you are trying to get the hostname, use:

ssh myServer "uname -n"

Answer 4

It is better to use a heredoc with ssh to avoid escaping quotes everywhere in a more complex command:

ssh -T myServer <<-'EOF'
uname -a | awk '{print $2}'
exit
EOF

Answer 5

Try this

ssh myServer "uname -a | awk '{print \$2}' "

Use the double quotes " in order to group the commands you will execute remotely.

You also need to escape the $ in the $2 argument, so that it is not calculated locally, but passed on to awk remotely.

Edit:

If you want to include the $( ), you again have to escape the $ symbol, like this:

ssh myServer "echo \$(uname -a | awk '{print \$2}') "

You can also escape the backtick `, like this:

ssh myServer "echo \`uname -a | awk '{print \$2}'\` "

Answer 6

Just some additional note:

In my case, the escape of the $ doesn't help:

ts1350:> ssh sysadm@node "grep feature features.txt| awk '{print $6}' "
Password: 
A  feature   -name  ue_trace_mme    | off
ts1350:> ssh sysadm@node "grep feature features.txt| awk '{print \$6}' "
Password: 
awk: cmd. line:1: {print \}
awk: cmd. line:1:        ^ backslash not last character on line
awk: cmd. line:1: {print \}
awk: cmd. line:1:        ^ syntax error
ts1350:> ssh sysadm@node "grep feature features.txt| awk '{print \\$6}' "
Password: 
awk: cmd. line:1: {print \\}
awk: cmd. line:1:        ^ backslash not last character on line
awk: cmd. line:1: {print \\}
awk: cmd. line:1:        ^ syntax error

While add a space between $ and the number works:

Fri Oct  4 14:49:28 CEST 2019
ts1350:> ssh sysadm@node "grep feature features.txt| awk '{print $ 6}' "
Password: 
off

Hope this secodnary way help someone like me.

Thanks to @dave in his answer: How to print a specific column with awk on a remote ssh session?