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Delete line from remote file over ssh passing variable

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# 1  
Old 11-08-2019
Delete line from remote file over ssh passing variable

I have a variable called $a1 which maps to something like "http://servername proxy1 count http" and a lots of entries in a file on remote server.
If I have the following in my .sh script:
sed -i "\%$a1%d" mylog.txt

the line is deleted from mylog.txt. Great.
I'm trying now to remvoe this from a remote server too:
echo $a1 | ssh -q -i ~/.ssh/mysshkey remoteserver "sed -i \"\%$a1%d\" mylog.txt"

This doesn't work. I also tried
 echo $a1 | ssh -q -i ~/.ssh/mysshkey remoteserver "sed -i '\%$a1%d\' mylog.txt"

Which also doesn't work.

I am missing something obvious?
# 2  
Old 11-08-2019
Hi, you do not need the echo $a1 | part.

ssh -q -i ~/.ssh/mysshkey remoteserver "sed -i '\%$a1%d' mylog.txt"

There was a backslash before the last single quote.

Last edited by Scrutinizer; 11-08-2019 at 01:43 PM..
# 3  
Old 11-14-2019
Thanks for the spot.

It didn't quite work as you suggested, but when I added the echo back in, it worked. Many thanks:
echo $a1 | ssh -q -i ~/.ssh/mysshkey remoteserver "sed -i '\%$a1%d' mylog.txt"

# 4  
Old 11-14-2019
The echo $a1 | ssh ... redirects stdin - but nothing reads from it.
You can just redirect stdin with </dev/null ssh ... or close stdin with ssh -n ...; that should have the same effect and not confuse anybody.
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