I am trying to escape the following script to run it via shell command-string option ( /bin/sh -c ).
privateIP=$(ifconfig eth0 | grep "inet " | awk \'{print $2}\');
sed -i "s/http:\/\/:/http:\/\/$privateIP:/g" init.conf
Please elaborate on the answer.
You're question is not clear, but perhaps you are looking for:
sh -c 'privateIP=$(ifconfig eth0 | awk "/inet/{print \$2}");
sed -i "s#http://:#http://$privateIP:#g" init.conf'
Related
I'm working on a script, that should find certain disks and add hostname to them.
I'm using this for 40 servers with a for loop in bash
#!/bin/bash
for i in myservers{1..40}
do ssh user#$i findmnt -o SIZE,TARGET -n -l |
grep '1.8T\|1.6T\|1.7T' |
sed 's/^[ \t]*//' |
cut -d ' ' -f 2 |
awk -v HOSTNAME=$HOSTNAME '{print HOSTNAME ":" $0}'; done |
tee sorted.log
can you help out with the quoting here? It looks like awk gets piped (hostname) from localhost, not the remote server.
Everything after the first pipe is running locally, not on the remote server.
Try quoting the entire pipeline to have it run on the remote server:
#!/bin/bash
for i in myservers{1..40}
do ssh user#$i "findmnt -o SIZE,TARGET -n -l |
sed 's/^[ \t]*//' |
cut -d ' ' -f 2 |
awk -v HOSTNAME=\$HOSTNAME '{print HOSTNAME \":\" \$0}'" ;
done | tee sorted.log
This is a shorter version of your stuff:
findmnt -o SIZE,TARGET -n -l |
awk -v HOSTNAME=$HOSTNAME '/M/{print HOSTNAME ":" $2}'
Applied to the above:
for i in myservers{1..40}
do ssh user#$i bash -c '
findmnt -o SIZE,TARGET -n -l |
awk -v HOSTNAME=$HOSTNAME '"'"'/M/{print HOSTNAME ":" $2}'"'"' '
done |
tee sorted.log
see: How to escape the single quote character in an ssh / remote bash command?
I am trying to execute a command based on extracting it from README file.
I was able to extract it using grep and sed:
cat README.md | grep -i "docker build" | grep -vi "dockerfile.debug" | sed 's/.*\(d[a-z]\).*/\1/'
This script would give a result something like 'docker build .'
I want to execute that command.
But I am not sure how to execute the extracted text. I thought 'exec' would work but I couldn't apply it. Please help me find a way to execute the text extracted through the above script.
Set your command in
$(CommandToExecute)
or back-ticks
`CommandToExecute`
As Example:
$(cat README.md | grep -i "docker build" | grep -vi "dockerfile.debug" | sed 's/.*\(d[a-z]\).*/\1/'
);
try:
$(grep -i "docker build" README.md | grep -vi "dockerfile.debug" | sed 's/.*\(d[a-z]\).*/\1/')
I'm trying to create script to be run by cron to create multiple folders with subfolders.
DATE=`date +%Y-%m-%d`
IP_ADDR=`ifconfig | grep -v '127.0.0.1' | sed -n 's/.*inet addr:\([0-9.]\+\)\s.*/\1/p'`
/bin/mkdir -p /mnt/db-backup/12/$DATE/$IP_ADDR/
If i run this script manually everything is created as expected. When script is ran by cron subdirectory $IP_ADDR is not created and there is no errors.
I suspect that /sbin is not part of the PATH for the environment that the cron job runs under. You should specify the full path for the ifconfig command:
IP_ADDR=$(/sbin/ifconfig | grep -v '127.0.0.1' | sed -n 's/.*inet addr:\([0-9.]\+\)\s.*/\1/p')
It's also better practice (in general) to use $() for command substitution.
Try to use debug mode :
set -x
DATE=`date +%Y-%m-%d`
IP_ADDR=`ifconfig | grep -v '127.0.0.1' | sed -n 's/.*inet addr:\([0-9.]\+\)\s.*/\1/p'`
/bin/mkdir -p /mnt/db-backup/12/$DATE/$IP_ADDR/
set +x
Then, redirect the output of your cron to a file and have a look, you should find useful information in it.
You are not far off, but there are several ordering caveats that could cause problems. Many systems have different formats for the ifconfig output line. Some with inet xxx.xxx.xxx.xxx, others with inet addr:xxx.xxx.xxx.xxx. (those are the two most common). You may also need to handle the case where there are multiple wired inet interfaces (2+ NICs in the box). However, if you have only 1 NIC, you could try the following to handle the common ifconfig formats:
DATE=`date +%Y-%m-%d`
IP_ADDR=$(ifconfig |
grep -v '127.0.0.1' |
grep -E 'inet[ ](addr:)*[0-9]{1,3}([.][0-9]{1,3}){3}' |
sed -e 's/^.*inet \(addr:\)*//' -e 's/ .*$//')
/bin/mkdir -p /mnt/db-backup/12/$DATE/$IP_ADDR/
or with IP_ADDR written as one line:
IP_ADDR=$(ifconfig | grep -v '127.0.0.1' | grep -E 'inet[ ](addr:)*[0-9]{1,3}([.][0-9]{1,3}){3}' | sed -e 's/^.*inet \(addr:\)*//' -e 's/ .*$//')
When running the command:
puts `ssh -o StrictHostKeyChecking=no -i keyfile user#host "sudo cat file | awk '/^server/ {print \$2}' | sort -u"`
After running this command, its only counts the ^server, but it ignores the print $2 command.
i get the whole line instead of just the 2nd word.
You're running through a couple of shell processing layers, so you need an additional backslash:
puts `ssh -o StrictHostKeyChecking=no -i keyfile user#host "sudo cat file | awk '/^server/ {print \\$2}' | sort -u"`
What happens if you change this:
sudo cat file | awk '/^server/ {print \$2}' | sort -u
to this:
sudo cat file | grep '/^server' | awk '{ print \$2 }' | sort -u
If still not working, try not escaping the $ - try $2 instead of \$2
Might be more maintainable to split it up into pieces. Also using ruby's single quoting mechanism works to send the command as you intend.
cmd = %q(sudo cat file | awk '/^server/ {print $2}' | sort -u)
puts %x(ssh -o StrictHostKeyChecking=no -i keyfile user#host #{cmd})
Problem description:
I want to print only the source and destination address from a tcpdump[1].
Have one working solution, but believe it could be improved a lot. An example that captures 5 packets, just as an example of what I'm looking for:
tcpdump -i eth1 -n -c 5 ip | \
cut -d" " -f3,5 | \
sed -e 's/^\([0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\)\..* \([0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\).*$/\1 > \2/'
Question:
Can this be done in any easier way? Performance is also an issue here.
[1] A part of a test if the snort home_net is correctly defined, or if we see traffic not defined in the home_net.
Solution:
Ok, thanks to everyone who have replied to this one. There have been two concerns related to the answers, one is the compatibility across different linux-versions and the second one is speed.
Here is the results on the speed test I did. First the grep-version:
time tcpdump -l -r test.dmp -n ip 2>/dev/null | grep -P -o '([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+).*? > ([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)' | grep -P -o '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' | xargs -n 2 echo >/dev/null
real 0m5.625s
user 0m0.513s
sys 0m4.305s
Then the sed-version:
time tcpdump -n -r test.dmp ip | sed -une 's/^.* \(\([0-9]\{1,3\}\.\?\)\{4\}\)\..* \(\([0-9]\{1,3\}\.\?\)\{4\}\)\..*$/\1 > \3/p' >/dev/null
reading from file test.dmp, link-type EN10MB (Ethernet)
real 0m0.491s
user 0m0.496s
sys 0m0.020s
And the fastest one, the awk-version:
time tcpdump -l -r test.dmp -n ip | awk '{ print gensub(/(.*)\..*/,"\\1","g",$3), $4, gensub(/(.*)\..*/,"\\1","g",$5) }' >/dev/null
reading from file test.dmp, link-type EN10MB (Ethernet)
real 0m0.093s
user 0m0.111s
sys 0m0.013s
Unfortunately I have not been able to test how compatible they are, but the awk needs gnu awk to work due to the gensub function. Anyway, all three solutions works on the two platforms I have tested them on. :)
Here's one way using GNU awk:
tcpdump -i eth1 -n -c 5 ip | awk '{ print gensub(/(.*)\..*/,"\\1","g",$3), $4, gensub(/(.*)\..*/,"\\1","g",$5) }'
Try this:
tcpdump -i eth1 -n -c 5 ip 2>/dev/null | sed -r 's/.* ([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+).* > ([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+).*/\1 > \2/'
If running from a .sh script, remember to escape \1 & \2 as required.
Warning You have to use unbuffered ou line-buffered output to monitor the output of another command like tcpdump.
But you command seem correct.
To simplify, you could:
tcpdump -i eth1 -n -c 5 ip |
sed -une 's/^.* \(\([0-9]\{1,3\}\.\?\)\{4\}\)\..* \(\([0-9]\{1,3\}\.\?\)\{4\}\)\..*$/\1 > \3/p'
Notice the u switch usefull without -c 5 at tcpdump
tcpdump -ni eth1 ip |
sed -une 's/^.* \(\([0-9]\{1,3\}\.\?\)\{4\}\)\..* \(\([0-9]\{1,3\}\.\?\)\{4\}\)\..*$/\1 > \3/p'
& here is a grep only solution:
tcpdump -l -i eth1 -n -c 5 ip 2>/dev/null | grep -P -o '([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+).*? > ([0-9]+\.[0-9]+\.[0-9]+\.[0-9]+)' | grep -P -o '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+' | xargs -n 2 echo
Note -l, in case you don't want to limit the number of packets using -c.