Bash script for service to check mount before start

Question

I need to insert on some service scripts a condition on the top to check whether a device is mounted or not.

I'm not very familiar with bash script...

This is a first try I wrote but it doesn't work.

### START CHECK
volume="/media/MyMountName"
if ! mount | grep "on ${volume} type" > /dev/null
then
    exit;
fi
### END CHECK

#... rest of the service script

This is another solution I'd like best:

### START CHECK
volume="/media/MyMountName"
delay=5

while ! mount | grep "on ${volume} type" > /dev/null
do
    sleep $delay
    if delay >= 60
    then
        exit;
    $delay = $dealy + 5
done
### END CHECK

#... rest of the service script

The second one should try to check the mount for a minute before giving up and exit without running the service.

Answer 1

while ! mount | grep "on ${volume} type" > /dev/null; do
    sleep $delay
    if [ "$delay" -gt 60 ]; then
        exit
    fi
    delay=$((delay+5))
done

using /proc/mounts

You might consider using /proc/mounts instead of the output of mount (which is just /etc/mtab).

while ! grep " ${volume} " /proc/mounts &>/dev/null; do

Answer 2

You're pretty close. How about:

### START CHECK
start_check_mtpt() { 
 local volume="$1"
 local delay=5
 local tries=$[ 60 / delay ]
 local mounted=0

 while [[ 0 = $mounted ]] && [[ $tries -ge 0 ]]; do
   if cut -d' ' -f2 /etc/mtab | grep -qF "${volume}" ; then
      mounted=1
      # optional: break
   else
    sleep $delay
    let tries=tries-1
   fi
 done
 [[ 1 = $mounted ]]
 return $?
}
### END CHECK

start_check "/media/MyMountName"

Answer 3

There are several answers to this question. If you want to check, whether a specifc device is mounted or not (i.e. your backup device), then you should check it by its UUID, which you can find out by issuing blkid.

UUID="place the UUID here"
TRIES=0
DEVFILE=""

while [[ -z $DEVFILE ]] && [[ $TRIES -lt 5 ]]; do
   DEVFILE=$(blkid -U $UUID)
   TRIES=$(( $TRIES + 1 ))
   sleep 5
done

if [ $TRIES -lt 5 ]; then
   MOUNTPOINT=$(findmnt -f $DEVFILE | tail -n1 | cut -d" " -f1)
   echo "found your device at $MOUNTPOINT"
fi