bash script to check hamachi status and perform reset tasks if applicable

check-hamachi.sh

#!/opt/bin/bash    # Synology (requires bash from entware-ng or optware[-ng])
# #!/bin/bash  # Other *nix

############# EDIT BLOCK ##############
array_ping_list=("25.1.2.3" "25.2.3.4" "25.3.4.5") #only the IP's expected always-on
array_network_list=("my.net" "my-other.net") #all your networks independent of IP's
log_file=~/check-hamachi.log
#### OS dependent config:
## Linux:
hamachi_service_stop="sudo /etc/init.d/logmein-hamachi stop"
hamachi_service_start="sudo /etc/init.d/logmein-hamachi start"
hamachi_tool=/usr/bin/hamachi
##--for synology, try:
# hamachi_service_stop="kill -15 $(ps | grep [h]amachid | awk '{print $1}')"
# hamachi_service_start="sh /opt/logmein-hamachi/hamachid.sh"
# hamachi_tool="sh /opt/logmein-hamachi/hamachi.sh"
##--end synology
##--for OSX, try:
# hamachi_service_stop="sudo launchctl stop com.logmein.hamachi"
# hamachi_service_start="sudo launchctl start com.logmein.hamachi"
# hamachi_tool=#locate your tool
##--end OSX
########### END EDIT BLOCK ############

array_ping_list_size=${#array_ping_list[@]}
ping_fail_count=0

dt=$(date +"%Y-%m-%d %H:%M")

function hamachi_reset {
	echo "${dt} - hamachi ${ping_fail_count}/${array_ping_list_size} failures; Full-reset" | tee -a ${log_file}
	${hamachi_service_stop}
	sleep 3
	${hamachi_service_start}
	sleep 7
	${hamachi_tool} logout
	sleep 7
	${hamachi_tool} login
	sleep 7
}

function hamachi_go_online {
	echo "${dt} - hamachi ${ping_fail_count}/${array_ping_list_size} failures; hamachi go-online; " | tee -a ${log_file}
	for (( j = 0 ; j < ${#array_network_list[@]} ; j++ )) ; do
		${hamachi_tool} go-online ${array_network_list[$j]}
		sleep 3
	done
}

if (${hamachi_tool} | grep "logged in" > /dev/null )
then
	echo "hamachi already logged in."
	echo "pinging ${array_ping_list_size} neighbors:"

	for (( i = 0 ; i < ${array_ping_list_size} ; i++ )) ; do
		if ! ( ping -c 1 -W 2 "${array_ping_list[$i]}" > /dev/null 2>&1 ) ;
		then
			echo "${array_ping_list[$i]} offline"
			((ping_fail_count++))
		else
			echo "${array_ping_list[$i]} online"
		fi
	done

	if [ ${ping_fail_count} -eq ${array_ping_list_size} ]
	then
		hamachi_reset
		hamachi_go_online
	elif [ ! ${ping_fail_count} -eq 0 ] && [ ${ping_fail_count} -lt ${array_ping_list_size} ]
	then
		hamachi_go_online
	else
		echo "${dt} - hamachi ${ping_fail_count}/${array_ping_list_size} failures; no action taken" | tee -a ${log_file}
	fi
else
	hamachi_reset
	hamachi_go_online
fi

changed ping -c 1 -W 1 to ping -c 1 -W 2 because some links are slow, and script would unnecessarily [re]start services.

Be sure to add your PATH=... in crontab; otherwise scripts will not work as expected (especially OSX).