UNIX for Dummies Questions & Answers

I'm trying to monitor disk usage, using cron to run a script to email me when disk capacity exceeds 66%. When I use df (actually, "df -k" because I find the format useful), disk capacity shows as field 5. However, that field includes a % which is confusing my ">" comparison to include a warning.

My goal: monitor disk usage every hour (cron: 0 * * * *), take disk usage info from "df -k" and if disk usage exceeds 2/3 (66%) email me a warning.

There are many ways to skin this cat. If you have a more efficient way, I'm open to suggestions.

Thanks.

i have something like this in my shell's start up file, so every time i log on, i will get a warning if it goes over 90%....customize it to your liking:

Code:

#### check disk space on filesystems listed
filesystems=(/ /boot /storage1)
for fs in ${filesystems[@]}; do
    disk_space=`df -h | grep -E $fs$ | awk '{print $(NF-1)}'`
    max_space="90"
    disk_space=${disk_space:-$((max_space-1))}
    [[ "${disk_space%'%'}" -ge "$max_space" ]] && { clear ; echo -e "\nWARNING...DISK SPACE ON \"$fs\" IS AT $disk_space\n"; }
done
unset filesystems fs disk_space max_space
####

In the array "filesystems" i have the mount point of every filesystem i want to check...

I guess the important part for you is the "${disk_space%'%'}" part, which will strip off that '%' sign

Thanks. That got me off and running. I found a slightly different way of getting rid of the % sign, but there must be some elementary syntax error I'm making:

$ df -k | sed 's/%//' | awk if ($5 > 66) {print $0} | mailx -s "WARNING: Disk usage exceeded limit" invisibleman@domain.com

Error message: syntax error near unexpected token `($' For clarity, that's ` ( $ '

Any ideas, anyone?

Try this way, as the output of df will multiple lines, so need to exclude and get only filesystem mount point...

df -k | sed 's/%//'|grep -vE "^/dev|^Filesystem" |awk '{if ( $4 > 43 ) print $0 }'

Thanks!