topic Re: if evaluation doesn't work fine in Operating System - Linux

if evaluation doesn't work fine

Carles Viaplana — Tue, 30 May 2006 03:52:01 GMT

Hello,

I've following script:

"check_disk2" 10 lines, 330 characters
# ./check_disk2 75 90 /dev/vglabccs/lvol1
DISK CRITICAL - [7926736 used (39%) on /dev/vglabccs/lvol1]
# more check_disk2
FREE="$(bdf $3 | tail -1 | cut -d ' ' -f 21)"
PERC="$(bdf $3 | tail -1 | cut -d ' ' -f 25 | cut -d % -f 1)"

if [ $FREE -gt $2 ] ; then
echo "DISK CRITICAL - [$FREE used ($PERC%) on $3]"
elif [ $FREE -gt $1 ] ; then
echo "DISK WARNING - [$FREE used ($PERC%) on $3]"
else
echo "DISK OK - [$FREE used ($PERC%) on $3]"
fi

PERC is filesystem used percentage (without "%") and $1 and $2 are numbers. Problem is when I check if PERC is greater than $2 or $1 as always show DISK CRITICAL message:

# ./check_disk2 75 90 /dev/vglabccs/lvol1
DISK CRITICAL - [7926736 used (39%) on /dev/vglabccs/lvol1]
# ./check_disk2 20 20 /dev/vglabccs/lvol1
DISK CRITICAL - [7926736 used (39%) on /dev/vglabccs/lvol1]
#

I think problem is script check values as strings instead numbers, so it can evaluate as I need.

How can I evaluate them as numbers?

Thanks in advande for your help.
Regards,

Carles

Re: if evaluation doesn't work fine

Peter Godron — Tue, 30 May 2006 04:05:21 GMT

Re: if evaluation doesn't work fine

Kenan Erdey — Tue, 30 May 2006 04:12:01 GMT

bdf $3 | tail -1 | cut -d ' ' -f 25 | cut -d % -f 1, is this ok ?

is there 25. field in bdf's output ?

Re: if evaluation doesn't work fine

Carles Viaplana — Tue, 30 May 2006 04:39:36 GMT

Thanks for your replies.

Both bdf commands has numbers (I already checked it).

About Peter message, I need numbers instead strings in order to evaluate if percentage I get with bdf command is greater than number I pass as parameter.

Thanks for your help.
Regards,

Carles

Re: if evaluation doesn't work fine

James R. Ferguson — Tue, 30 May 2006 05:07:35 GMT

Hi Carles:

You need to test 'PERC' not 'FREE' since 'PERC' has had the "%" string trimmed:

if [ $PERC -gt $2 ] ; then
echo "DISK CRITICAL - [$FREE used ($PERC%) on $3]"
elif [ $PERC -gt $1 ] ; then

Regards!

...JRF...

Re: if evaluation doesn't work fine

Carles Viaplana — Tue, 30 May 2006 05:14:08 GMT

Joder! You're right!

I was evaluating wrong variable, so script and if construction are fine.

Thanks for showing my little mistake that will allows me save a lot of work to some people.

Regards,

Carles