Case Study 3

Nslookup :- it can be use to troubleshoot if the private URL or a server name is not connecting while we can connect with the IP of the server. It helps to analyse any DNS related issue.

$ nslookup google.com

Curl:- Curl can be used to check if application URL is reachable. It can also be use for checking reachability of specific port on server.

$ curl google.com

$ curl -vvv google.com {To diagnose in detail when URL is not reachable}

$curl -I -vvvx.x.x.x:22 {To diagnose port connectivity for destination}

Telnet: Iti s used to verify if access to port on destination server is reachable.

$ telnet x.x.x.x 22 { press Shift+6 followed by ] to exit}

Ping: it is used to check reachability of destination IP address from source.It sends ICMP packets to verify connectivity.

$ping x.x.x.x

Traceroute: To check the path to reach destination.

$ traceroute x.x.x.x

Wget: to download software or patches from destination on your linux machine.

$wgethttps://cdn.kernel.org/pub/linux/kernel/v4.x/linux-4.17.2.tar.xz