why doesnot internet explorer open up websites?

[ITlover]

In an office the computer uses an isp dialup service to connect to internet.
The computer is successfully connected to the internet using dialup but after power failure for some time, the computer was again successfully connected to internet using the same isp dialup but the internet explorer wasn't opening any website and at the bottom of the internet explorer window ,it was saying something like "DNS error".

I wanted to know that should i have restarted the computer after the return of light(power) and then used internet?

When does the IP address of a machine assigned by the DNS Server of the ISP changes?
Does the IP address of a machine changes when the power returns or it changes when we restart the computer?

I couldnot find any solution to this problem except for running the "Ipconfig /flushdns" command in command prompt and then disconnected the ISP service ,restarted the computer ,reconnected the ISP dialup and the problem was solved ,the internet explorer started to open websites without problem.


I donot understand one thing, that their is a specific period for which the DNS Server assigns IP address to the machine and it only expires when the period of that IP address ends.
But i have heard that the dynamic IP configuration changes when we restart the computer.

I need some clarification.

The Computer uses WinXP with SP2 .

[glc]

The power failure probably corrupted your local DNS cache and the flush command reset it.

[Great_One]

fyi,
DNS servers don't assign ip addresses, DHCP servers do.
DNS servers resolve hostnames to ip addresses or vice versus.

[ITlover]

Thanks GLC for your reply, u mean to say that i was successfully connected to the internet through dialup service but i wasn't able to access websites because my local DNS cache wasn't resolving the host names of the websites into IP addresses, right?

Their is one more thing that i wan'ted to know ,do all the websites have their own IP address and are the websites stored in single servers?

the websites like www.yahoo.com and www.hotmail.com are stored only in their own servers?

Thanks for correcting me Great one, its DHCP(Dynamic Host Configuration Protocol) that assigns IP address dynamically.

By the way what is the difference between fully qualified domain name and host name?


Regards,

[Great_One]

Originally Posted by ITlover By the way what is the difference between fully qualified domain name and host name? Regards,

Hostname is basically your name of your computer or other device.
(or an A record or CNAME record in a DNS zone file)

a fully qualified name is your hostname plus your domain name plus your tld.

example:

DNS A record: www (hostname)
domain name: google
tld: com

fqd: www.google.com

[glc]

No, DNS is propagated globally. When you try to load a site, it will first check your local cache for the address, if found, that's what it uses. If your cache is bad, it bombs out. If it's not found in the cache, then it looks at your ISP's DNS server for the address and caches it for next time.