Connectivity Testing

connectivity-testing.sh

# method 1: if icmp is enabled in the target server then 
ping $DESTINATION_IP

# method 2: run telnet on a port where a service is listening. The target port must be binded (a service listening) so the test can be performed. 
telnet $DESTINATION_IP $PORT

# method 3 in case there is no service listening you can ask the target server owner/operator to install netcat. 
## A. In the destination server run netcat with -l <port>. Netcat will bind to the specified port in order to listen. This is handy when there is no services running but want to ensure connectivity exists. 
netcat -l $PORTNUMBER
## B. In the source server you can run telnet or netcat in order to test the connectivity to the destination server: 
telnet $DESTINATION_IP $PORT 
# or 
netcat -vz $DESTINATION_IP $PORT