Troubleshooting Network Connectivity (4)

June 14th, 2008

Most people mix “network connectivity” and “working browser” together, which means, if they can’t use their browser to browse the internet, they will say that they are not connected.  And yes, they e-mail tech support complaining that they don’t have network connectivity.

Alright, customers are always right.  So it’s the little peon’s job to figure out what they are really complaining about.  Top reasons for a non-working browser are

  1. DNS service is down
  2. Infected by malware
  3. The home page web site is down
  4. Protection software conflict

First and most is the DNS service is down.  DNS servers are responsible to translate human-readable names to actual IP addresses.  For example, translate www.cchsu.com to some IP address that can be used by machines to do their jobs.  Your ISP typically maintain a DNS service for you, and as you all know, it’s just as reliable as your DSL/cable service, which means it can be down.  For some ISPs that I used to use, it can be as frequent as twice a day, although each time the down time is roughly 10 minutes.  As a result, it is important that you write down the DNS servers’ addresses so that you can ping or tracert to see if you can reach them.  If the DNS servers are down, all that you can do is waiting.

Let’s summarize what we have now:

  • We are sure the router is working fine without hardware failures
  • We are sure what needs to be plugged is plugged firmly (if on wired network), and we are sure the wireless link is working (if on wireless network)
  • We have an valid IP address and we can reach the router from our machine
  • We can reach the DNS server from our machine, and nslookup works fine

If you reached this far, you can almost be certain that something in the software level is preventing the network connectivity.  We are going to cover that in next article.

Uncategorized | Comments Jump to the top of this page

Comments are closed.

Chef Peon's Melange

Archives

Meta

Social Links