I'm trying to automate the user creation(Bulk Users) in Linux. So, I've created a text file with all the needed parameters for user's creation.
The Text file contains the below content:
tom:tom1:588:0:test user1:/home/test:/bin/false
harry:harry1:589:0:test test2:/hom/test2:/bin/nologin
Trying to use awk command to print the column's in for loop and create the users with the information's from /tmp/user.txt
for userdetails in $(cat /tmp/user.txt)
do
user=`echo $userdetails | awk -v FS=: '{print $1}'`
passwd=`echo $userdetails | awk -v FS=: '{print $2}'`
uid=`echo $userdetails | awk -v FS=: '{print $3}'`
gid=`echo $userdetails | awk -v FS=: '{print $4}'`
comment=`echo $userdetails | awk -v FS=: '{print $5}'`
home_dir=`echo $userdetails | awk -v FS=: '{print $6}'`
user_shell=`echo $userdetails | awk -v FS=: '{print $7}'`
useradd -d "$home_dir" -c "$comment" -s "$user_shell" -u "$uid" -g "$gid" "$user"
echo "$passwd" | passwd "$user" --stdin;
done
Actual Output:
useradd: invalid home directory ''
passwd: Unknown user name 'tom'.
useradd: invalid home directory ''
passwd: Unknown user name 'user1'.
useradd: invalid home directory ''
passwd: Unknown user name 'harry'.
useradd: invalid home directory ''
passwd: Unknown user name 'test2'.
What I'm doing wrong ?
P.S : I am aware there is a command called newusers in Linux, but i need to check the same via script to create bulk users in Linux.
idk how you got started on that track but you're off-base. Just use a shell loop:
while IFS=':' read -r user passwd uid gid comment home_dir user_shell; do
useradd -d "$home_dir" -c "$comment" -s "$user_shell" -u "$uid" -g "$gid" "$user"
echo "$passwd" | passwd "$user" --stdin;
done < /tmp/user.txt
The above is just showing how to read the file contents into variables, it assumes you know what you're doing with the "useradd" and "passwd" lines.
I would use while for read a file by line so the entire line will be stored in the variable you choose( in my case: line) . Then you could echo variable and awk will do the rest of the work. I prefer $() than `` so I use both for now. For this much data you could create a loop into the while to make code sorter and better manageable.
cat /tmp/user.txt | while read line
do
user=`echo $line | awk -F ":" '{print $1}'`
passwd=$(echo $line | awk -F ":" '{print $2}')
uid=$(echo $line | awk -F ":" '{print $3}')
gid=$(echo $line | awk -F ":" '{print $4}')
comment=$(echo $line | awk -F ":" '{print $5}')
home_dir=$(echo $line | awk -F ":" '{print $6}')
user_shell=$(echo $line | awk -F ":" '{print $7}')
useradd -d "$home_dir" -c "$comment" -s "$user_shell" -u "$uid" -g "$gid" "$user"
echo "$passwd" | passwd "$user" --stdin;
done
If you are stuck with awk, you can use Awk Global substitution:
awk '{gsub(/:/,"-")} 1' your_file
This is also feasible using sed with the g flag ( Sed Global substitution ):
sed "s/:/-/g" your_file
In both casesn your edited lines would be printed to the screen.
Related
I have a linux script for selecting the node.
For example:
4
40*r13n15:40*r10n61:40*r11n18:40*r09n15
The correct result should be:
r13n15
r10n61
r11n18
r09n15
My linux script content is like:
hostNum=`bjobs -X -o "nexec_host" $1 | grep -v NEXEC`
hostSer=`bjobs -X -o "exec_host" $1 | grep -v EXEC`
echo $hostNum
echo $hostSer
for i in `seq 1 $hostNum`
do
echo $hostSer | awk -F ':' '{print '$i'}' | awk -F '*' '{print $2}'
done
But unlucky, I got nothing about node information.
I have tried:
echo $hostSer | awk -F ':' '{print "'$i'"}' | awk -F '*' '{print $2}'
and
echo $hostSer | awk -F ':' '{print '"$i"'}' | awk -F '*' '{print $2}'
But there are wrong. Who can give me a help?
One more awk:
$ echo "$variable" | awk 'NR%2==0' RS='[*:\n]'
r13n15
r10n61
r11n18
r09n15
By setting the record separtor(RS) to *:\n , the string is broken into individual tokens, after which you can just print every 2nd line(NR%2==0).
You can use multiple separators in awk. Please try below:
h='40*r13n15:40*r10n61:40*r11n18:40*r09n15'
echo "$h"| awk -F '[:*]' '{ for (i=2;i<=NF;i+=2) print $i }'
**edited to make it generic based on the comment from RavinderSingh13.
I'd like to change my script(s) so that the command output is separated by a comma and is all on one line per host. Any ideas on how I can achieve this:
1st Script:
#!/bin/bash
for i in `cat ~/hostnames.txt`
do
ssh -q $i 'bash -s' < server_info.sh
done
2nd Script (server_info.sh):
#!/bin/bash
echo -n "Name: "
uname -n
echo -n "CPUs: "
cat /proc/cpuinfo* | grep processor | wc -l
echo -n "Memory (kb): "
cat /proc/meminfo | grep MemTotal: | awk '{print $2}'
echo -n "Current Kernel: "
uname -a | awk '{print $3}'
echo -n "IP: "
hostname -i
echo -e
Changing your 1st script:
#!/bin/bash
for i in cat ~/hostnames.txt
do
ssh -q $i 'bash -s' < server_info.sh
done | awk -v RS= '{$1=$1}1'
Note: Your server_info.sh can be a lot more optimized.For example:
cat /proc/meminfo | grep MemTotal: | awk '{print $2}'
could be changed to:
awk '/MemTotal:/{print $2}' /proc/meminfo
I have a task which asks to write a script which displays all partitions formatted with a specific file system, given as parameter.
I have written the script but when i run it it displays '0'. What am i doing wrong?
This is my code:
#!/bin/bash
n=sudo parted -l | tail -n +8 | awk '{print $5}' | wc | awk '{print $2}'
m=sudo parted -l | tail -n +8 | awk '{print $5}'
q=sudo parted -l | tail -n +8
for i in $n; do
if [ "[ $m | sed -n ip ]" = "$1" ]; then
echo "$q | sed -n ip"
fi
done
Different approach from yours, but does it do what you need?
lsblk -f | awk '$0 ~ fs {print $NF}' fs=ext2
I have a tomcat server I am trying to get a list of info on for a project. I need to get the results from /etc/default/tomcat file. However some of my servers are tomcat6 and some are tomcat7 so hardcoding the filename is not going to work.
How would I dynamically insert the filename in this batch script.
#!/bin/bash
echo Server Name: `hostname`
echo CPU: `top -b -n1 | grep "Cpu(s)" | awk '{print $2 + $4}'`
FREE_DATA=`free -m | grep Mem`
CURRENT=`echo $FREE_DATA | cut -f3 -d' '`
TOTAL=`echo $FREE_DATA | cut -f2 -d' '`
echo Internal IP : `ifconfig eth0 2>/dev/null|awk '/inet addr:/ {print $2}'|sed 's/addr://'`
echo OS Memory: `cat /proc/meminfo | grep MemTotal | awk '{ print $2 }'`
echo Operating System: `uname -mrs`
***echo Tomcat Memory: `cat /etc/default/tomcat6 | grep Xmx | awk '{ print $5}'`***
Your last command can be simplified to single awk like this:
awk '/Xmx/{print "Tomcat Memory:", $5}' "$tomcatFile"
Pass "$tomcatFile" whatever tomcat filename from ver6 or ver7.
You can get output from both tomcat files in same command using:
awk '/Xmx/{print "Tomcat Memory:", $5}' /etc/default/tomcat[67]
I am running below script:-
#!/bin/bash
threshold="20"
i=2
result=`df -kh |grep -v “Filesystem” | awk ‘{ print $5 }’ | sed ‘s/%//g’`
for percent in $result; do
if ((percent > threshold))
then
partition=`df -kh | head -$i | tail -1| awk ‘{print $1}’`
echo “$partition at $(hostname -f) is ${percent}% full”
fi
let i=$i+1
done
But I get the following error:
awk: ‘{
awk: ^ invalid char '▒' in expression
sed: -e expression #1, char 1: unknown command: `▒'
Please help me to resolve this.
What awk does not work? (your script does work fine on my Ubuntu)
This line:
result=`df -kh |grep -v "Filesystem" | awk '{ print $5 }' | sed 's/%//g'`
could be changed to:
result=$(df -kh | awk '!/Filesystem/ {print $5+0}')
Avoid using old and outdated backtics if parentheses works like this: var=$(code...)
This:
partition=`df -kh | head -$i | tail -1| awk '{print $1}'`
could be changed to:
partition=$(df -kh | awk -v line="$i" 'NR==line {print $1}')
This
let i=$i+1
could be change to:
((i++))
This would then give some like this:
#!/bin/bash
threshold="20"
i=2
result=$(df -kh | awk '!/Filesystem/ {print $5+0}')
for percent in $result; do
if ((percent > threshold))
then
partition=$(df -kh | awk -v line="$i" 'NR==line {print $1}')
echo "$partition at $(hostname -f) is ${percent}% full"
fi
((i++))
done
You're using ‘ for a single quote not '. Try re-encoding your file with an editor.
You got the answer to your syntax error, now re-write the whole script as just:
#!/bin/bash
df -kh |
awk -v t=20 -v h="$(hostname -f)" '(NR>1)&&($5+0>t){printf "%s at %s is %s full\n",$1,h,$5}'