[bantejas]

Originally Posted by pranavt

Yes! Change your whole operating system because you can't view one website. Brilliant advice!

I was just kidding man!
On a serious note it is not for only one website. It is for the softwares around Windows that costs a bomb and you need to keep updating the anti-virus software too. Linux doesn't require any anti-virus because most of the hackers are linux geeks who want the Microsoft out! Anyways, it is and I can go on and on about it.

I didn't know about the DNS being changed simply because I didn't/don't have any issues accessing the site. Didn't know that it was a MTNL problem.

[GTO]

Is there anyway in which we can force MTNL servers into updating their DNS entries & our new location?

[extreme_torque]

Originally Posted by greenhorn

a bit OT: I hate OPENDNS - they redirect everything to their own search engine. searching using the address bar is not possible

I use opendns and dont face this problem. I am using chrome.... IE is so 90's :P

[nehamit]

Originally Posted by greenhorn

a bit OT: I hate OPENDNS - they redirect everything to their own search engine. searching using the address bar is not possible

Hi! There is no need to hate Open DNS. Here is the trick to use Google Search with OpenDNS:
Firefox
Type about:config in the address bar and press enter. If you are on Firefox 3, click “I’ll be careful, I promise!”. Now type keyword.url in the Filter field and set the value as:

Google (Please right click, and select copy link location)

Also make sure that the value of keyword.enabled is set to TRUE.
IE
Open the registry editor (Start -> Run -> regedit) and navigate to the following key in the registry:

HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\SearchScopes
Select {51337F48-5CBB-4E52-AFC2-77B7BE2CF6EA} and enter the value of URL as http://www.google.com/search?q={searchTerms}

That's all! Now you will not be forcefully redirected to OpenDNS search engine!

I use OpenDNS with this hack successfully for quite a long time. I found this while searching the web. Do not remember where, but I have saved this note on my computer.

[Rehaan]

Originally Posted by bantejas

Can you explain to me why is this required?

Bantejas,

Simply put, when you type a web address using words, the computer needs to change it into an IP address in order to find that server.

A DNS server has a list of all webaddress + their corresponding IP address.

So when you type www.team -bhp.com it looks it up on the DNS server and the corresponding IP address (currently
96.30.20.23) is found.

(You can also just type 96.30.20.23 in the address bar and it works!)

However, the thing is, a lot of times the IP address of the site changes, so unless the DNS list is also updated frequently, this can cause problems.


I guess a good parallel to draw could be :

Think of a DNS server as your cellphone phonebook.
By choosing to dial a Persons name it actually calls the persons number.

Now if you want to call John Doe and his number in your phonebook hasn't been updated (since he recently changed it), you're not going to get through!

Originally Posted by greenhorn

a bit OT: I hate OPENDNS - they redirect everything to their own search engine. searching using the address bar is not possible

In addition / as an alternative to what nehamit has said, if you use firefox you can do it in a much simpler way.


To set this up, click on the search engine icon on the top-right of the screen (usually the google G). Select "Manage Search Engines..."

Then add the keyword "g" for google ...or whatever you want.




Now, to search, you will have to type

g <searchterm>

in the address bar.


cya
R

[ghpk]

Originally Posted by GTO

Is there anyway in which we can force MTNL servers into updating their DNS entries & our new location?

Call their customer care and check if you can get details of the supervisor.
Or if possible write a letter to them, I am sure they must be aware of Team-BHP existence and they can Sync their zones with not much efforts, but as its a SARKARI think sometimes they rely on their pre-set timing of DNS look ups which may be set as "update in Ages "

I think their NOC is in Agra.

[deepclutch]

another alternate for opendns is dns advantage.

[bantejas]

Originally Posted by Rehaan

Bantejas,

Simply put, when you type a web address using words, the computer needs to change it into an IP address in order to find that server.
....
Now if you want to call John Doe and his number in your phonebook hasn't been updated (since he recently changed it), you're not going to get through!

R

Rehaan,

I know a little on how the DNS works. I am not sure of what happens when IP of a site changes, how much time does the local DNS take to update itself etc. Since caching time for each of the local DNS server is different, one can't access the the site if the local DNS server (e.g., MTNL) is not updated with the central DNS server (with which the site is registered).

Other way is to basically keep resolving each time you access the site which is not good from an implementation perspective because it then will load the DNS server.

Just wiki'ed it: Excerpts from it:

Many people incorrectly refer to a mysterious 48 hour or 72 hour propagation time when you make a DNS change. When one changes the NS records for one's domain or the IP addresses for hostnames of authoritative DNS servers using one's domain (if any), there can be a lengthy period of time before all DNS servers use the new information. This is because those records are handled by the zone parent DNS servers (for example, the .com DNS servers if your domain is example.com), which typically cache those records for 48 hours. However, those DNS changes will be immediately available for any DNS servers that do not have them cached. And any DNS changes on your domain other than the NS records and authoritative DNS server names can be nearly instantaneous, if you choose for them to be (by lowering the TTL once or twice ahead of time, and waiting until the old TTL expires before making the change).

link: Domain Name System - Wikipedia, the free encyclopedia


Thanks,
Tejas

[GTO]

Originally Posted by ghpk

Call their customer care and check if you can get details of the supervisor.
Or if possible write a letter to them, I am sure they must be aware of Team-BHP existence and they can Sync their zones with not much efforts, but as its a SARKARI think sometimes they rely on their pre-set timing of DNS look ups which may be set as "update in Ages "

I think their NOC is in Agra.

Thanks. A request has been made this week and hopefully, they implement the change at the earliest.

[lancer_rit]

Originally Posted by bantejas

Rehaan,

I know a little on how the DNS works. I am not sure of what happens when IP of a site changes, how much time does the local DNS take to update itself etc. Since caching time for each of the local DNS server is different, one can't access the the site if the local DNS server (e.g., MTNL) is not updated with the central DNS server (with which the site is registered).

Not really. The caching time as per the DNS protocol depends on the primary zone server which publishes the record to other zone servers. If my DNS server is the primary DNS server for zone abc.com, then the address update of xyz.abc.com should happen when the expiry time configured in the record for xyz.abc.com in my DNS server is over. At that time, if an user tries to resolve xyz.abc.com, other DNS servers need to recursively query up the DNS hierarchy till they get the latest record from the primary or secondary DNS servers for abc.com.
It is true that many primary DNS servers are configured for expiry intervals of 24/48 hours. That seems reasonable, when you think about how many times does a domain name's IP change ...

[SirAlec]

i am using mtnl delhi and its working fine.

[GTO]

i am using mtnl delhi and its working fine.

Maybe our request has already gone through. Thanks!

[whatcanthisbe]

Using MTNL in delhi and not able to get on here ... .:( I have noted the IP and will try from home using this IP

[bantejas]

Originally Posted by lancer_rit

It is true that many primary DNS servers are configured for expiry intervals of 24/48 hours. That seems reasonable, when you think about how many times does a domain name's IP change ...

I don't think that the domains name's IP changes frequently. I believe that they are given a single or pool of (I am not too sure about this either) ip addresses all of which are anyways cached in the DNS server.

Pardon me as I have never worked on/read about DNS (except for the wiki that I did a few days back) and this is purely my thoughts of how it can work.

Tejas

[FlyingSpur]

MTNL user. No problems whatsoever.