Output not displaying after echo - bash

I'm trying to format my output based on the result of a certain command. However, it's not printing out. Can you guys let me know what I am missing out.
VID=$(grep -iE $vvwwn ${TPAR_TEMP}/vvid_${TPAR_NAME} > ${TPAR_TEMP}/tvvid 2> /dev/null)
TVVID=$(cat ${TPAR_TEMP}/tvvid |awk '{print$3}' 2> /dev/null)
if [ "${TVVID}" = "32" ]; then
sh templ1
echo "$VID"
else
sh templ2
echo "$VID"
fi
templ1 is
#!/bin/bash
echo "========================================================================================================"
awk '
BEGIN {printf "%-27s %-6s %-32s %-8s %-8s %-9s %-4s\n" , "Name", "State", "VV_WWN", "VSize_MB", "Usr_Used_MB", "UsrCPG", "Prov"}'
echo "========================================================================================================"

The problem is with $VID been empty due to the redirect in the command grep -iE $vvwwn ${TPAR_TEMP}/vvid_${TPAR_NAME} > ${TPAR_TEMP}/tvvid, To make the problem easier fill in the variables and run the command in your terminal.

Related

bash check if string exists in output

I have the following bash script:
#!/bin/bash
KEY=$(./get-aws-profile.sh --profile=$1 --key)
SECRET=$(./get-aws-profile.sh --profile=$1 --secret)
ES="https://search-****.eu-west-1.es.amazonaws.com"
INDEXES=$(AWS_ACCESS_KEY_ID="$KEY" AWS_SECRET_ACCESS_KEY="$SECRET" aws-es-curl $ES/_cat/indices | awk '{print $3}')
YESTERDAY=$(date --date="yesterday" +"%Y.%m.%d")
for i in $INDEXES
do
# $i is like report-processing-2019.10.10
if grep "$YESTERDAY" $i; then
echo "Pulling documents from $i to $i.ndjson"
echo "docker run -it blaze blaze --host=$ES --index=$i --insecure > /tmp/$i.ndjson"
echo "Index $i saved"
else
echo no
fi
done
exit 0
where $i is like report-processing-2019.10.10
when i run this, i am not able to get the the lines which contain only lines with 2019.10.10 in them, what am i missing?
any advice is much appreciated

Bash Script can run php script manually but cannot work in Cron

I have a bash script like this:
#!/bin/bash
log_file=/home/michael/bash/test.log
checkalive=checkalive.php
#declare
needRestart=0
#Check checkalive.php
is_checkalive=`ps aux | grep -v grep| grep -v "$0" | grep $checkalive| wc -l | awk '{print $1}'`
if [ $is_checkalive != "0" ] ;
then
checkaliveId=$(ps -ef | grep $checkalive | grep -v 'grep' | awk '{ printf $2 }')
echo "Service $checkalive is running. $checkaliveId"
else
echo "$checkalive OFF"
needRestart=1
fi
#NEED needRestart
if [ $needRestart == "1" ];
then
#START SERVICE
echo "Restarting services..."
/usr/bin/php5.6 /home/michael/bash/$checkalive >/dev/null 2>&1 &
echo "$checkalive..."
echo `date '+%Y-%m-%d %H:%M:%S'` " Start /home/michael/bash/$checkalive" >> $log_file
fi
I can run it manually but when I try to run it in Cron, it doesn't work for some reasons. Apparently the command:
/usr/bin/php5.6 /home/michael/bash/$checkalive >/dev/null 2>&1 &
does not work.
All of file permissions are already set to executable. Any advice?
Thank you
You have run into one of cron's most common mistakes, trying to use it like an arbitrary shell script. Cron is not a shell script and you can't do everything you can do in one, like dereferencing variables or setting arbitrary new variables.
I suggest you replace your values into the cron line and avoid usage of variables
/usr/bin/php5.6 /home/michael/bash/checkalive.php >/dev/null 2>&1 &
Also, consider removing the trailing & as it is not necessary.

Two "if" conditions in the same time

I am writing a script to bring me data from other nodes via ssh in a multi selection choice menu, and i want to display a message according to this data.
if [[ "$option" == "1" ]]
then
ssh skyusr#<IP> "export JAVA_HOME=/opt/mesosphere && /var/lib/mesos/slave/slaves/*/frameworks/*/executors/*/runs/latest/apache-cassandra-3.0.10/bin/nodetool -p 7199 status" | sed -n '6,10p' | awk '{print $1,$2}' | grep DN > $file_name
if [ -s $file_name ]
then
echo "All Cassandra Nodes are UP !"
else cat "$file_name"
fi
fi
When i execute the script, i see it does not see the second if condition to display the message .
What is the correct syntax ?
There is, as far as I can see, nothing wrong with the syntax. You might want to do something about spacing etc. to enhance readability, but that is it.
I assumed, that file_name is set somewhere before this part, as is option.
If things do not work as you expect them to work, you can add some statements for debugging purposes, which you must remove later on. For example, in this case, I would like to see the output of the ssh and add some echo's to see the flow-control:
if [[ "$option" == "1" ]] ; then
ssh skyusr#<IP> "export JAVA_HOME=/opt/mesosphere && /var/lib/mesos/slave/slaves/*/frameworks/*/executors/*/runs/latest/apache-cassandra-3.0.10/bin/nodetool -p 7199 status" > tempfile
cat tempfile |
sed -n '6,10p' |
awk '{print $1,$2}' |
grep DN > "$file_name"
if [ -s "$file_name" ] ; then
echo "All Cassandra Nodes are UP !"
else
echo "$file_name is not empty"
cat "$file_name"
fi
fi
You can use the tempfile to verify that your sed, awk, grep combination acts correctly.

How can I check if 'grep' doesn't have any output?

I need to check if the recipient username is in file /etc/passwd which contains all the users in my class, but I have tried a few different combinations of if statements and grep without success. The best I could come up with is below, but I don't think it's working properly.
My logic behind it is that if the grep is null, the user is invalid.
send_email()
{
message=
address=
attachment=
validuser=1
until [ "$validuser" = "0" ]
do
echo "Enter the email address: "
read address
if [ -z grep $address /etc/passwd ]
then
validuser=0
else
validuser=1
fi
echo -n "Enter the subject of the message: "
read message
echo ""
echo "Enter the file you want to attach: "
read attachment
mail -s "$message" "$address"<"$attachment"
done
press_enter
}
Just do a simple if like this:
if grep -q $address /etc/passwd
then
echo "OK";
else
echo "NOT OK";
fi
The -q option is used here just to make grep quiet (don't output...)
Use getent and check for grep's exit code. Avoid using /etc/passwd. Equivalent in the shell:
getent passwd | grep -q valid_user
echo $?
Output:
0
And:
getent passwd | grep -q invalid_user
echo $?
Output:
1
Your piece of code:
if [ -z grep $address /etc/passwd ]
You haven't saved the results of grep $address /etc/passwd in a variable. Before putting it in the if statement and then testing the variable to see if it is empty.
You can try it like this:
check_address=`grep $address /etc/passwd`
if [ -z "$check_address" ]
then
validuser=0
else
validuser=1
fi
The -z check is for variable strings, which your grep isn't giving. To give a value from your grep command, enclose it in $():
if [ -z $(grep $address /etc/passwd) ]
The easiest one will be this:
cat test123
# Output: 12345678
cat test123 | grep 123 >/dev/null && echo "grep result exist" || echo "grep result doesn't exist"
# Output: grep result exist
cat test123 | grep 999 >/dev/null && echo "grep result exist" || echo "grep result doesn't exist"
# Output: grep result doesn't exist
My problem was that the file I was trying to grep was a binary file. On windows, the first two characters in the file were little squares. On mac, the first two characters were question marks. When I used more or less on the file, I could see it was binary and when I used diff, it responded that the "Binary files foo.log and requirements.txt differ".
I used cat to display the contents of the file, highlighted and copied the text (minus the two question marks at the top, deleted the file, created a new file with touch and then used vi to paste the text back into the new file.
After that, grep worked fine.
Shorter:
until ! grep $address /etc/passwd ; do {
do_your_stuff
}

How to egrep variable-Unix shell script

I’m trying to validate input by using egrep and regex.Here is the line from script (c-shell):
echo $1 | egrep '^[0-9]+$'
if ($status == 0) then
set numvar = $1
else
echo "Invalid input"
exit 1
endif
If I pipe echo to egrep it works, but it also prints the variable on the screen, and this is something I don't need.
To simply suppress output you can redirect it to the null device.
echo $1 | egrep '^[0-9]+$' >/dev/null
if ($status == 0) then
set numvar = $1
else
echo "Invalid input"
exit 1
endif
You might also want to consider using the -c option to get the count of matches instead of using using the status.
Also, unless you are using csh, the status is stored in $? not in $status
grep has a -q option that suppresses output
So:
egrep -q '^[0-9]+$'
you can use awk
$ echo "1234" | awk '{print $1+0==$1?"ok":"not ok"}'
ok
$ echo "123d4" | awk '{print $1+0==$1?"ok":"not ok"}'
not ok

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