PING and Traceroute
Packet Internet Groper (PING) is an excellent tool to troubleshoot network connectivity. In the PING exercise, I have chosen britishairways.com and rj.com even though both are airlines abroad; however, the PING and traceroute are probably sending me to the closest server. On the PING test, all packets were 32 bytes, and time ranged from 33ms to 67ms; Time To Live(TTL) was very high, with a minimum of 48 routers and a maximum of 55 routers between each IP location. The trace route shows that rj.com had the most hops, with 13 hops to reach the destination. PING and traceroute are excellent tools but give you different information. PING will let you know if the device or server is there and gives you a statistic of how fast the connection is. Traceroute could be used to figure out the routing table or router that does not let you get to the device. A firewall and router that has disabled this ICMP protocol may be why PING does not work. Sometimes this protocol is disabled to hide a DMZ between the Wide area network(WAN) and the Local area network(LAN). Tracert could show timeout when a recent network change has not been updated in the routing tables. A situation like this could be when Network B best route is through Network A. However, a backup route to Network B is Network C. The router between network A and B stops responding. However, the routing protocol has not detected it and updated the routing tables to go through Network C in all the routers in the network. At this point, PING will timeout, and traceroute will timeout beyond Network A. I had a problem like this one at my work months ago where the VPN users could not route to our location from corporate and the Network Administrator had to push a routing table update to all the routers in the SDWAN.
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