The script will disable any proxy server first. Then it will use ping to test connectivity to the proxy server for up to two minutes. If unable to reach the proxy server, it does nothing more. If the device gets a reponse from the ping, it will set the auto proxy URL and enable. Use this with a Jamf policy triggered by Network State Change and e…

ToggleProxyOnOff.sh

#!/bin/sh

# enter the DNS or IP address of the network proxy
proxyAddress="proxy.domain.com"

# create a list of all Wi-Fi and Ethernet services
interfaces=$( networksetup -listallnetworkservices | egrep "Wi-Fi|Ethernet" )

# always turn of proxy configuration first for each network interface
while IFS= read anInterface
do
    networksetup -setautoproxystate "$anInterface" off
done <<< "$interfaces"

# attempt to ping the proxy for up to two minutes
for i in {1..120} # for 120 seconds
do
    ping -c1 "$proxyAddress" && break # attempt to ping the proxy
    sleep 1
done

# make one last attempt to ping and get result
ping -c1 "$proxyAddress" && break # attempt to ping the proxy

# if ping reaches the proxy, enable the proxy URL for Wi-Fi and Ethernet interfaces
if [ $? = 0 ]; then
    while IFS= read anInterface
    do
        networksetup -setautoproxyurl "$anInterface" "http://$proxyAddress"
    done <<< "$interfaces"
fi

exit 0