(Help Required) Run script only if able to ping Google

[faria]

(Solved) Run script only if able to ping Google

Hi Guys,
Basically i want the router to update the host file from my adblock but only to do so if it can ping Google if not then quit.

here is my current script:

#!/bin/sh

rm -f /tmp/adblock/hosts.downloaded
sh /jffs/scripts/adblock

the new script would follow this logic:

#!/bin/sh
# if ping google successful  then run the commands below, if not then quit.

rm -f /tmp/adblock/hosts.downloaded
sh /jffs/scripts/adblock

(note)the script is run by a cronjob.

Any help writing this script is most welcome.

 

[ColinTaylor]

#!/bin/sh

if ping -c 2 8.8.8.8 > /dev/null
then
	rm -f /tmp/adblock/hosts.downloaded
	sh /jffs/scripts/adblock
fi

8.8.8.8 is one of google's public DNS servers, so should be reliable. Also, using the IP address rather than its host name means you're not reliant on your local DNS service being available.

 

[coldwizard]

#!/bin/sh
# should work
ping -c 1 google.com
if  test "$?" == "0"
then
 echo "worked"
else
 echo "Failed"
fi
# should fail
ping -c 1 172.17.7.7
if  test "$?" == "0"
then
 echo "worked"
else
  echo "Failed"
fi

 

[faria]

Thanks guys! Very much appreciated.

-c Xnumber means the number of pings tried, correct ?

 

[ColinTaylor]

Thanks guys! Very much appreciated.

-c Xnumber means the number of pings tried, correct ?

Correct. If any of the pings fail an error code is returned.

# ping
BusyBox v1.20.2 (2014-06-06 16:30:42 EDT) multi-call binary.

Usage: ping [OPTIONS] HOST

Send ICMP ECHO_REQUEST packets to network hosts

        -4,-6           Force IP or IPv6 name resolution
        -c CNT          Send only CNT pings
        -s SIZE         Send SIZE data bytes in packets (default:56)
        -t TTL          Set TTL
        -I IFACE/IP     Use interface or IP address as source
        -W SEC          Seconds to wait for the first response (default:10)
                        (after all -c CNT packets are sent)
        -w SEC          Seconds until ping exits (default:infinite)
                        (can exit earlier with -c CNT)
        -q              Quiet, only displays output at start
                        and when finished

#