I'm trying to make a simple bash script that will iterate through a text file containing IP addresses,
ping them one time, and see if they are alive or not.
This is my work so far:
#!/bin/bash
for ip in $(cat ips.txt); do
if [[ "1" == "$(ping -c 1 $ip | grep 'packets transmitted' | cut -d ' ' -f 4)"]]
echo $ip
fi
done
Any Suggestions?
Thanks!
This seems to work:
#!/bin/bash
for ip in $(cat ips.txt); do
if [ "1" == "$(ping -c 1 $ip | grep 'packets transmitted' | cut -d ' ' -f 4)" ]; then
echo $ip
fi
done
You needed the ; then after the if [ ... ] statement (same thing goes for elif, not else), and a space between the last bracket of the statement and the statement's contents. Also this appears to work fine with just single brackets, and this may be more portable (see here).
Works on Bash 4.2.47
Yes. You can use a newline instead of ; if you like, but you always need the then keyword.
if [ "1" == "$(ping -c 1 $ip | grep 'packets transmitted' | cut -d ' ' -f 4)" ]
then echo $ip
fi
# or
if [ "1" == "$(ping -c 1 $ip | grep 'packets transmitted' | cut -d ' ' -f 4)" ]
then
echo $ip
fi
Related
#!/bin/bash
a=2
b=2
COUNTER=0
sam="abcd"
sam1="xyz"
sam2="mno"
for x in ls | grep .rpm
do
`C=rpm -qpR $x | grep -v CompressedFileNames | grep -v PayloadFilesHavePrefix | wc -l`
if [ "sam2"!="$sam1" ]
then
echo "${sam1}"
echo "${sam2}"
if [ $C -eq $a ]
then
COUNTER=$((COUNTER+1))
echo "${x}"
eval sam=$x
#eval sam1=sam | cut -d '-' -f 1
sam1=`echo "${sam}"| cut -d '-' -f 1`
if [ $COUNTER -eq $b ]
then
break
fi
fi
fi
sam2=`echo "${x}"| cut -d '-' -f 1`
done
This is the output I am getting:
xyz
mno
comps-4ES-0.20050107.x86_64.rpm
comps
comps
comps-4ES-0.20050525.x86_64.rpm
My question is: why is the if condition returning true despite sam1 and sam2 being equal? I have checked for non-equality.
Response is the same even if I use
if [ $C -eq $a ] && [ "$sam2" != " $sam1" ]
As Ansgar Wiechers pointed out, you're missing a "$" in front of the sam2 variable. That way, you're comparing the literal string "sam2" with the string value of $sam1 (which initially is set to "xyz"). What you want to do is compare the string values of both variables:
if [ "$sam2" != "$sam1" ]
Regarding $C, you should only include the commands to be evaluated inside backticks, not the evaluation itself. This is called a command substitution - a subshell is created in which the commands are executed, and the backtick expression is substituted by the computed value. The line should look like this:
C=`rpm -qpR $x | grep -v CompressedFileNames | grep -v PayloadFilesHavePrefix | wc -l`
Your for loop also needs a command substitution: for x in ls | grep .rpm makes it look as if you're piping the output of a for command into grep. What you want to do is iterate over the ls | grep part, which you can do with the following command substitution:
for x in `ls | grep .rpm`
Hi Guys Got the solution:
#!/bin/bash
read -p "enter dep number" a
read -p "enter no of rpms" b
COUNTER=0
sam="abcd"
sam1="xyz"
sam2="mno"
for x in `ls | grep .rpm`
do
C=`rpm -qpR $x |grep -v CompressedFileNames | grep -v PayloadFilesHavePrefix | wc -l`
# echo "${C}:c"
if [ $C -eq $a ] && [ "$sam2" != "$sam1" ]
then
COUNTER=$((COUNTER+1))
# echo "${COUNTER}:counter"
# echo "${x}"
eval sam=$x
#eval sam1=sam | cut -d '-' -f 1
sam1=`echo "${sam}"| cut -d '-' -f 1`
if [ $COUNTER -eq $b ]
then
break
fi
fi
sam2=`echo "${x}"| cut -d '-' -f 1`
#echo "${sam2}"
#echo "${sam1}"
done
I've overlooked my program for any mistakes and can't find any. Usually when I run into a mistake with BASH the interpreter is off on where the mistake is. I'm trying to customize this script from SANS InfoSec Using Linux Scripts to Monitor Security. Everything is fine until the part where the check function looks at the different protocols. When I uncomment them I get the error: ./report: line 41: [: too many arguments. Here is the program...
#!/bin/bash
if [ "$(id -u)" != "0" ]; then
echo "Must be root to run this script!"
exit 1
fi
##### CONSTANTS -
report=/home/chron/Desktop/report.log
#router=/home/chron/Desktop/router.log
red=`tput bold;tput setaf 1`
yellow=`tput bold;tput setaf 3`
green=`tput bold;tput setaf 2`
blue=`tput bold;tput setaf 4`
magenta=`tput bold;tput setaf 5`
cyan=`tput bold;tput setaf 6`
white=`tput sgr0`
##### FUNCTIONS -
pingtest() {
ping=`ping -c 3 localhost | tail -2`
loss=`echo $ping | cut -d"," -f3 | cut -d" " -f2`
delay=`echo $ping | cut -d"=" -f2 | cut -d"." -f1`
if [ "$loss" = "100%" ]; then
echo -n $red$1$white is not responding at all | mail -s'REPORT' localhost
echo 'You have mail in /var/mail!'
echo `date` $1 is not responding at all >> $report
elif [ "$loss" != "0%" ]; then
echo $yellow$1$white is responding with some packet loss
else
if [ "$delay" -lt 100 ]; then
echo $green$1$white is responding normally
else
echo $yellow$1$white is responding slow
fi
fi
}
check() {
if [ "$2" != "" -a "$2" $3 ] ; then
echo -n $green$1$white' '
else
echo -n $red$1$white' '
echo `date` $1 was not $3 >> $report
fi
}
##### __MAIN__ -
pingtest localhost # hostname or ip
echo "Server Configuration:"
check hostname `hostname -s` '= localhost'
check domain `hostname -d` '= domain.com'
check ipaddress `hostname -I | cut -d" " -f1` '= 10.10.0.6'
check gateway `netstat -nr | grep ^0.0.0.0 | cut -c17-27` '= 10.10.0.1'
echo
echo "Integrity of Files:"
check hostsfile `md5sum /etc/hosts | grep 7c5c6678160fc706533dc46b95f06675 | wc -l` '= 1'
check passwd `md5sum /etc/passwd | grep adf5a9f5a9a70759aef4332cf2382944 | wc -l` '= 1'
#/etc/inetd.conf is missing...
echo
#echo "Integrity of Website:"
#check www/index.html `lynx -reload -dump http://<LOCALIP> 2>&1 | md5sum | cut -d" " -f1 '=<MD5SUM>'
#echo
echo "Incoming attempts:"
#lynx -auth user:password -dump http://10.10.0.1 >> $router 2>&1
check telnet `grep \ 23$ $PWD/router.log | wc -l` '= 0'
check ftp `grep \ 21$ $PWD/router.log | wc -l` '= 0'
check ssh `grep \ 22$ $PWD/router.log | wc -l` '=0'
check smtp `grep \ 25$ $PWD/router.log | wc -l` '=0'
check dns `grep \ 53$ $PWD/router.log | wc -l` '=0'
echo
Some of the lines are commented out for later tweaking. Right now my problem is with the protocols. Not sure what's wrong because it looks like to me there are 3 arguments for the function.
In your last three calls to check, you are missing the required space between the operator and the operand.
check ssh `grep \ 22$ $PWD/router.log | wc -l` '=0'
check smtp `grep \ 25$ $PWD/router.log | wc -l` '=0'
check dns `grep \ 53$ $PWD/router.log | wc -l` '=0'
The final argument to all of these should be '= 0'.
However, this is not a good way to structure your code. If you really need to parameterize the comparison fully (all your calls use = as the operation), pass the operator as a separate argument. Further, written correctly, there is no need to pre-check that $2 is a non-empty string.
check() {
if [ "$2" "$3" "$4" ] ; then
printf '%s%s%s ' "$green" "$1" "$white"
else
printf '%s%s%s ' "$red" "$1" "$white"
printf '%s %s was not %s\n' "$(date)" "$1" "$3" >> "$report"
fi
}
Then your calls to check should look like
check hostname "$(hostname -s)" = localhost
check domain "$(hostname -d)" = domain.com
check ipaddress "$(hostname -I | cut -d" " -f1)" = 10.10.0.6
check gateway "$(netstat -nr | grep ^0.0.0.0 | cut -c17-27)" = 10.10.0.1
etc
Run your code through http://shellcheck.net; there are a lot of things you can correct.
Here is my other problem. I changed it up a bit just to see what's going on.
router=/home/chron/Desktop/router.log
check() {
if [ "$2" "$3" "$4" ]; then
printf "%s%s%s" "$green" "$1" "$white"
else
printf "%s%s%s" "$red" "$1" "$white"
printf "%s %s was not %s\n" "$(date)" "$1" $3" >> report.log
fi
check gateway "$(route | grep 10.10.0.1 | cut -c17-27)" = 10.10.0.1
check telnet "$(grep -c \ 23$ $router)" = 0
check ftp "$(grep -c \ 21$ $router)" = 0
check ssh "$(grep -c \ 22$ $router)" = 0
check smtp "$(grep -c \ 25$ $router)" = 0
check dns "$(grep -c \ 53$ $router)" = 0
My aim is to transform the output (the last 2 lines) of the ping command in a CSV style.
Here are some examples:
In case there is a packet loss lower than 100% <
URL, PacketLoss, Min, Average, Max, Deviation
In case there is packet loss equal to 100%
URL, 100, -1, -1, -1, -1
My script is below, but when the packet loss is 100% the output is:
URL, 100,
So the problem is at the if statement, as it does not enter in elif, I use the same syntax as checking if the address is full or not (with "www." or not).
Can you please have a look because I tried multiple things and it did not work.
My script:
#!/bin/bash
declare site=''
declare result='';
if [[ "$1" == "www."* ]]; then
site="$1";
else
site="www.$1";
fi
result="$site";
pingOutput=$(ping $site -c10 -i0.2 -q| tail -n2);
fl=true;
while IFS= read -r line
do
# !!! The problem is here, the if statement is not working properly and I do not know why !!!
if [ "$fl" == "true" ]; then
result="$result $(echo "$line" | cut -d',' -f3 | cut -d" " -f2 | sed -r 's/%//g')";
fl=false;
elif [[ "$line" == "ms"* ]]; then
result="$result $(echo "$line" | cut -d' ' -f4 | sed -r 's/\// /g')";
else
result="$result -1 -1 -1 -1";
fi
done <<< "$pingOutput"
echo "$result";
This is a pretty old question but I've just stumbled upon it today. Below I paste a slight modified version of the above script that fixes the if issue and works on Mac OS.
P.S. You can uncomment the # prctg=100.0% line to see the if working.
#!/bin/bash
declare site=''
declare result=''
declare prctg=''
[[ "$1" == "www."* ]] && site="$1" || site="www.$1"
result="$site"
pingOutput=$(ping $site -c10 -i0.2 -q | tail -n2)
fl=true
while IFS= read -r line
do
#echo $line
if [ "$fl" == "true" ]
then
prctg=$(echo "$line" | grep -Eo "[.[:digit:]]{1,10}%")
result="$result,$prctg"
fl=false
# prctg=100.0%
else
if [ "$prctg" == "100.0%" ]
then
result="$result,-1,-1,-1,-1"
else
result="$result,$(echo "$line" | cut -d' ' -f4 | sed -E 's/\//,/g')"
fi
fi
done <<< "$pingOutput"
echo "$result"
I hope it helps someone from the future! :)
Since the second line of the pingOutput was never processed (the loop ended before) the action of adding the -1 to the output was never performed.
Due to this problem I decided to capture the percentage of failure and act when no packets were returned (100%), I also simplified some expressions you used initially.
I investigated the script and came up with the following solution:
#!/bin/bash
declare site=''
declare result=''
declare prctg=''
[[ "$1" == "www."* ]] && site="$1" || site="www.$1"
result="$site"
pingOutput=$(ping $site -c10 -i0.2 -q| tail -n2)
fl=true
while IFS= read -r line
do
# !!! The problem is here, the if statement is not working properly and I do not know why !!!
echo $line
if [ "$fl" == "true" ]
then
prctg=$(echo "$line" | grep -Po "[0-9]{0,3}(?=%)")
result="$result $prctg"
fl=false
fi
if [ "$prctg" == "100" ]
then
result="$result -1 -1 -1 -1"
else
result="$result $(echo "$line" | cut -d' ' -f4 | sed -r 's/\// /g')"
fi
done <<< "$pingOutput"
echo "$result"
I've written the bash script (searchuser) which should display all the users who are executing a specific program or a script (at least a bash script). But when searching for scripts fails because the command the SO is executing is something like bash scriptname.
This script acts parsing the ps command output, it search for all the occurrences of the specified program name, extracts the user and the program name, verifies if the program name is that we're searching for and if it's it displays the relevant information (in this case the user name and the program name, might be better to output also the PID, but that is quite simple). The verification is accomplished to reject all lines containing program names which contain the name of the program but they're not the program we are searching for; if we're searching gedit we don't desire to find sgedit or gedits.
Other issues I've are:
I would like to avoid the use of a tmp file.
I would like to be not tied to GNU extensions.
The script has to be executed as:
root# searchuser programname <invio>
The script searchuser is the following:
#!/bin/bash
i=0
search=$1
tmp=`mktemp`
ps -aux | tr -s ' ' | grep "$search" > $tmp
while read fileline
do
user=`echo "$fileline" | cut -f1 -d' '`
prg=`echo "$fileline" | cut -f11 -d' '`
prg=`basename "$prg"`
if [ "$prg" = "$search" ]; then
echo "$user - $prg"
i=`expr $i + 1`
fi
done < $tmp
if [ $i = 0 ]; then
echo "No users are executing $search"
fi
rm $tmp
exit $i
Have you suggestion about to solve these issues?
One approach might looks like such:
IFS=$'\n' read -r -d '' -a pids < <(pgrep -x -- "$1"; printf '\0')
if (( ! ${#pids[#]} )); then
echo "No users are executing $1"
fi
for pid in "${pids[#]}"; do
# build a more accurate command line than the one ps emits
args=( )
while IFS= read -r -d '' arg; do
args+=( "$arg" )
done </proc/"$pid"/cmdline
(( ${#args[#]} )) || continue # exited while we were running
printf -v cmdline_str '%q ' "${args[#]}"
user=$(stat --format=%U /proc/"$pid") || continue # exited while we were running
printf '%q - %s\n' "$user" "${cmdline_str% }"
done
Unlike the output from ps, which doesn't distinguish between ./command "some argument" and ./command "some" "argument", this will emit output which correctly shows the arguments run by each user, with quoting which will re-run the given command correctly.
What about:
ps -e -o user,comm | egrep "^[^ ]+ +$1$" | cut -d' ' -f1 | sort -u
* Addendum *
This statement:
ps -e -o user,pid,comm | egrep "^\s*\S+\s+\S+\s*$1$" | while read a b; do echo $a; done | sort | uniq -c
or this one:
ps -e -o user,pid,comm | egrep "^\s*\S+\s+\S+\s*sleep$" | xargs -L1 echo | cut -d ' ' -f1 | sort | uniq -c
shows the number of process instances by user.
new to bash scripting so just wondering if i am doing this code right at all. im trying to search /etc/passwd and then grep and print users.
usage ()
{
echo "usage: ./file.sk user"
}
# test if we have two arguments on the command line
if [ $# != 1 ]
then
usage
exit
fi
if [[ $# < 0 ]];then
usage
exit
fi
# Search for user
fullname=`grep $1 /etc/passwd | cut -f 5 -d :`
firstname=`grep $1 /etc/passwd | cut -f 5 -d : | cut -f 1 -d " "`
#check if there. if name is founf: print msg and line entry
not sure as how to this or if im doing this right...
am i doing this right?
grep $1 /etc/passwd | while IFS=: read -r username passwd uid gid info home shell
do
echo $username: $info
done
This might work for you:
fullname=$(awk -F: '/'$1'/{print $5}' /etc/passwd)
firstname=${fullname/ *}
You're on the right track.
But I think the 2nd if [[ $# < 0 ]] .... fi block doesn't get you much. Your first test case gets the situation right, 'This script requires 1 argument or quits'.
Also, I don't see what you need firstname for, so a basic test is
case "${fullname:--1}" in
-[1] ) printf "No userID found for input=$1\n" ; exit 1 ;;
* )
# assume it is OK
# do what every you want after this case block
;;
esac
You can of course, duplicate this using "${firstname}" if you really need the check.
OR as an equivalent if ... fi is
if [[ "${fullname}" == "" ]] ; then
printf "No userID found for input=$1\n" ; exit 1
fi
note to be more efficient, you can parse ${fullname} to get firstname without all the calls to grep etc, i.e.
firstname=${fullname%% *}
Let me know if you need for me to explain :--1} and %% *} variable modifiers.
I hope this helps.
Instead of this:
fullname=`grep $1 /etc/passwd | cut -f 5 -d :`
firstname=`grep $1 /etc/passwd | cut -f 5 -d : | cut -f 1 -d " "`
Try this:
fullname=$(cut -f5 -d: /etc/passwd | grep "$1")
if [[ $? -ne 0 ]]; then
# not found, do something
fi
firstname=${fullname%% *} # remove the space and everything after
Note that I changed my answer to cut before grep so that it doesn't get false positives if some other field matches the full name you are searching for.
You can simply by reading your input to an array and then printing out your desired fields, something like this -
grep $1 /etc/passwd | while IFS=: read -a arry; do
echo ${arry[0]}:${arry[4]};
done
Test:
jaypal:~/Temp] echo "root:*:0:0:System Administrator:/var/root:/bin/sh" |
while IFS=: read -a arry; do
echo ${arry[0]}:${arry[4]};
done
root:System Administrator