[SOLVED] sed command with /

gilesaj001 · 09-02-2021, 02:25 AM

I am trying to use the sed command like this

Code:

  sed -i 's/cd /usr/bin/prp/prpclient-1/#cd /usr/bin/prp/prpclient-1/g' /home/dingo/myscript.sh"

to change cd /usr/bin/prp/prpclient-1 to #cd /usr/bin/prp/prpclient-1

I get this error

Quote:

sed: -e expression #1, char 11: unknown option to `s'

I am not sure if it is the # or the / that is the problem. I am not a programmer and at 71 can't think as well as I used to.

I also want to use the command with pssh to change the file in multiple machines

Code:

  parallel-ssh -h hosts_file.txt -i "sed -i 's/cd /usr/bin/prp/prpclient-1/#cd /usr/bin/prp/prpclient-1/g' /home/dingo/myscript.sh"

but I also get an error.

Quote:

Exited with error code 1
Stderr: sed: -e expression #1, char 11: unknown option to `s'

Which us probably the same error.

Any help is always appreciated.

Turbocapitalist · 09-02-2021, 02:28 AM

The marker in the substitution command can be any character but has to be the same all the way through:

Code:

s/old/new/
s#old#new#
s|old|new|
s!old!new!
saoldanewa

And so on.

Also, the -i option can and probably should be used with an extension.

boughtonp · 09-02-2021, 08:12 AM

Quote:

Originally Posted by Turbocapitalist

Also, the -i option can and probably should be used with an extension.

I prefer a more explicit non-Sed backup, since it's easy to run a command with (e.g) -i.bak twice and wipe out the original.

gilesaj001 · 09-02-2021, 10:39 PM

I have tried using the ! as the separator and it works on it's own like

Code:

 sed -i 's!#cd /usr/bin/prp/prpclient-1!cd /usr/bin/prp/prpclient-1!' /home/dingo/myscript.sh

BUT whwn I try and use it with pssh like this

Code:

 parallel-ssh -h hosts_file.txt -i sed -i 's!#cd /usr/bin/prp/prpclient-1!cd /usr/bin/prp/prpclient-1!g' /home/dingo/myscript.sh

I get the error:

Quote:

[1] 23:37:39 [FAILURE] "IP ADDRESS" Exited with error code 1
Stderr: sed: -e expression #1, char 5: unterminated `s' command

The format for pssh is OK when I run this

Code:

root@dingo4:~# parallel-ssh -h hosts_file.txt -i "sed -i 's/work_buf_min_days>0.000000/work_buf_min_days>4.000000/g' /usr/bin/global_prefs_override.xml"
[1] 23:51:17 [SUCCESS] 158.69.
[2] 23:51:17 [SUCCESS] 158.69
[3] 23:51:17 [SUCCESS] 158.69.
[4] 23:51:17 [SUCCESS] 158.69.

I tried it with the "" like the one that works but I get another error:

Code:

parallel-ssh -h hosts_file.txt -i "sed -i 's!#cd /usr/bin/prp/prpclient-1!cd /usr/bin/prp/prpclient-1!g' /home/dingo/myscript.sh"

Quote:

-bash: !': event not found

chrism01 · 09-02-2021, 11:19 PM

For the bash shell '!' is special char. For example you can recall/rerun a prev cmd by giving it's cmd num from bash history eg

Code:

!996

will re-run cmd num 996 in your bash history...

Try ':' instead.

evo2 · 09-02-2021, 11:43 PM

Quote:

Originally Posted by boughtonp

it's easy to run a command with (e.g) -i.bak twice and wipe out the original.

This has happened to me nore times than I care to admit.

Evo2.

gilesaj001 · 09-03-2021, 12:02 AM

Quote:

Originally Posted by chrism01

For the bash shell '!' is special char. For example you can recall/rerun a prev cmd by giving it's cmd num from bash history eg

Code:

!996

will re-run cmd num 996 in your bash history...

Try ':' instead.

I tried : but get the same error

Code:

parallel-ssh -h hosts_file.txt -i "sed -i 's:#etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml"

But still get the same error

Quote:

[1] 01:00:48 [FAILURE] 158.69.1**.** Exited with error code 1
Stderr: sed: -e expression #1, char 5: unterminated `s' command
[2] 01:00:49 [FAILURE] 158.69.1**.** Exited with error code 1
Stderr: sed: -e expression #1, char 5: unterminated `s' command
[3] 01:00:49 [FAILURE] 158.69.**.** Exited with error code 1
Stderr: sed: -e expression #1, char 5: unterminated `s' command
[4] 01:00:49 [FAILURE] 158.69.1**.*** Exited with error code 1

pan64 · 09-03-2021, 02:04 AM

# is a special char too, so I would try escape that too.

Code:

parallel-ssh -h hosts_file.txt -i "\"sed -i 's:#etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml\""

probably works.

gilesaj001 · 09-04-2021, 12:49 AM

Quote:

Originally Posted by pan64

# is a special char too, so I would try escape that too.

Code:

parallel-ssh -h hosts_file.txt -i "\"sed -i 's:#etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml\""

probably works.

I think we are closer but I get the error

[4] 01:46:11 [FAILURE] 158.69.1**.*** Exited with error code 127
Stderr: bash: sed -i 's:#etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml: No such file or directory

Turbocapitalist · 09-04-2021, 01:14 AM

Is it GNU sed on all the other machines? Or do you need something fully portable? If GNU sed is present on each, then you might see if it is the pound sign causing the trouble and write it as octal instead:

Code:

parallel-ssh -h hosts_file.txt -i "sed -i 's:\o043etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml"

Just a random guess.

gilesaj001 · 09-05-2021, 12:53 AM

Quote:

Originally Posted by Turbocapitalist

Is it GNU sed on all the other machines? Or do you need something fully portable? If GNU sed is present on each, then you might see if it is the pound sign causing the trouble and write it as octal instead:

Code:

parallel-ssh -h hosts_file.txt -i "sed -i 's:\o043etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml"

Just a random guess.

Thank you that works, I knew it was the # as the error changed when it moved in the script but I did not know how to do it.

Turbocapitalist · 09-05-2021, 12:57 AM

It'll work on systems with GNU sed but no others.

I wonder if the problem isn't parallel-ssh there. Looking at the manual page for it, I don't see much anything standing out in the way of advantages over the normal SSH client launched with a while loop. Are you using any special features of Parallel-SSH or just the ability to read targets from a list?

gilesaj001 · 09-05-2021, 04:04 AM

I use it to send commands from one machine to a bunch of other machines. I have eight dedicated servers that I run BOINC on and 16 Pi 4's that I also use for BOINC. with pssh I can send one command from one machine and get it applied on all machines that I have in the hosts_file.txt.

If there is a simpler way then I am open to suggestions but I am not a programmer so it would have to be easy to follow..

Turbocapitalist · 09-05-2021, 05:02 AM

Quote:

Originally Posted by gilesaj001

I use it to send commands from one machine to a bunch of other machines. I have eight dedicated servers that I run BOINC on and 16 Pi 4's that I also use for BOINC. with pssh I can send one command from one machine and get it applied on all machines that I have in the hosts_file.txt.

If there is a simpler way then I am open to suggestions but I am not a programmer so it would have to be easy to follow..

Thanks.

Although there has been a bit of drift, all GNU/Linux systems are at their heart IDEs. So they are built around programming and scripting and, in reality, all interaction through the shell interpreter is actually scripting. So with that caveat:

Code:

while read host; do 
        ssh $host "sed -i.bak 's:#etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml"
done < hosts_file.txt

So while on the surface that looks like it adds two lines, underneath it allows use of the normal SSH client and re-uses pre-existing shell skills. Knowledge of shell scripting is a highly useful skill even with a small investment of time.

Maybe parallel-ssh is more appropriate, especially if you have hundreds or thousands of machines. However, the option for normal shell work is always.

MadeInGermany · 09-06-2021, 02:17 PM

Attention, ssh can read from the stdin, competing with the read!
Have
ssh -n ...
or
</dev/null ssh ...

An alternative is to pass a local script through ssh's stdin to the remote host.

Code:

while read host
do
  ssh $host /bin/bash -s <<"_EOT"
    sed -i.bak 's:#etc/init.d/boinc start:/etc/init.d/boinc start:g' /usr/bin/global_prefs_override.xml
_EOT
done < hosts_file.txt