?
Solved

faillover 3rd DNS Server

Posted on 2002-05-22
7
Medium Priority
?
201 Views
Last Modified: 2013-12-14
Hello,

At the moment we have a primary and a secundairy DNS. In case our internetconnection should cause troubles, we want to redirect our customers to a another webserver (different location) which for example displays a temp webpage.

Could this be done by using a 3rd DNS server located in a different area using a different zone-file?

I guess not because the secundairy dns'ses need to be exact the same as the primary. But is there some other way to do this?

Regards,

Rick
0
Comment
Question by:rmulder
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
  • 2
  • +1
7 Comments
 
LVL 5

Expert Comment

by:Mishou
ID: 7053668
Mulder,

You are concerned that if your Internet connection goes down your web site cannot be accessed.
When you registered your domain you specified 2 DNS servers.
I can think of a way to have your problem solved with the folowing configuration:
-install one DNS server at your location.
-install the other one somewhere else (or register with companies that provide DNS service).

The DNS at your location is the primary DNS specified in your zone and contain all the information the way that you want it.
The other DNS will contain same information except that your for www.company.com record will point to another webpage that display the temporary page.

This way when a client access your page, he will first contact the DNS at your location to translate www.company.com into an ip address.
If he cannot contact the first DNS specified on your zone, will try the next one.

There are some issues though with the fact that once one DNS is contacted that information is cached at the client side (for fast name resolution).
Maybe you will have to place a warning/description on the temp page asking the client to try to access the real page.

Hope this answer/help you.
Mishou
0
 

Author Comment

by:rmulder
ID: 7053674
It's not correct to think the 1st DNS is always used first. The 1st and 2nd DNS are being randomly chosen.

So i guess that's not going to work :-(


Gr,

Rick
0
 
LVL 5

Expert Comment

by:Mishou
ID: 7054564
I'm sure that when you register the zone (www.company.com) with the .com root server you actualy have to provide a primary and a secondary DNS server for your zone.
The random access of these 2 servers is configured using round robin or other form of balancing . But still there is a precedency created . primary and then secondary to be tried.

Or copy the site on the second webserver (in case the DNS access is random) and change the page on this server if the other link goes down (or have a monitoring tool to do this).

Mishou
 
0
 [eBook] Windows Nano Server

Download this FREE eBook and learn all you need to get started with Windows Nano Server, including deployment options, remote management
and troubleshooting tips and tricks

 
LVL 3

Expert Comment

by:Comply
ID: 7105025
You don't need a third DNS server. Just redirect to your seconary DNS server. Most web hosting companys have a utility just for this. I would make a image copy of my first DNS server, Then the they would never know they got redirected or your first server was down. Also if for any reason you lose a drive you can restore from the image back-up.
0
 
LVL 3

Expert Comment

by:Comply
ID: 7105317
You don't need a third DNS server. Just redirect to your seconary DNS server. Most web hosting companys have a utility just for this. I would make a image copy of my first DNS server, Then the they would never know they got redirected or your first server was down. Also if for any reason you lose a drive you can restore from the image back-up.
0
 
LVL 37

Accepted Solution

by:
meverest earned 2000 total points
ID: 7107571
mulder - you are correct - there is no way to determine which dns will service the reolver request.  if you try to do what has been suggested (ie different A records for different name servers) the reulst will be unpredictable.  keep in mind also that dns has caching component.  thus (for example) if a client af ISP 'x' looks at your web site in the morning, then their local DNS will resolve the hostname to IP address then cache that result for a time specified by the dns administrator of ISP 'x'.  therefore if your net connection fails, and (by some magic) a backup dns serves the address resolution as a different IP, those customers of ISP 'x' will still get a 'server not found' when attempting to hit your web site.

one method to acheive what you want is to use routing techniche instead of DNS.  the way this works is that you set up your backup server with exactly the same (REAL) IP address of your primary, even though it is on a physically different network.  use a dynamic routing protocol (like BGP is good for this sort of purpose) to advertise independent paths to these two locations.  if you load up the routes to your backup server, then when your primary site is online, then requests will always find their way to the primary server.  if it goes offline, then your border router will (obviously) stop advertising, so then the routes to the secondary location will kick in, and so direct requests to the backup server.

this is far more feasible technique than using something as inconsistent as DNS.

there are plenty of provisos and gotchas tho, so you'll need some fairly advanced network gear and plenty of nouse to get it working.

good luck! ;-)

cheers.

 
0
 

Author Comment

by:rmulder
ID: 7107733
tnx
0

Featured Post

Get your Conversational Ransomware Defense e‑book

This e-book gives you an insight into the ransomware threat and reviews the fundamentals of top-notch ransomware preparedness and recovery. To help you protect yourself and your organization. The initial infection may be inevitable, so the best protection is to be fully prepared.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Cable Modem Provisioning from DPoE compliant server  This Article is to support CMTS administrators to provide an overview of DOCSIS compliance configuration file, and to provision a cable modem located at customer place from a Back office serve…
Sometimes you have to pull out old tricks to get a new firewall to work… While we were installing a new Sonicwall at a customers site we found that sites they were able to visit before were not working.  It seemed random and we could not understa…
Do you want to know how to make a graph with Microsoft Access? First, create a query with the data for the chart. Then make a blank form and add a chart control. This video also shows how to change what data is displayed on the graph as well as form…
This tutorial will teach you the special effect of super speed similar to the fictional character Wally West aka "The Flash" After Shake : http://www.videocopilot.net/presets/after_shake/ All lightning effects with instructions : http://www.mediaf…
Suggested Courses
Course of the Month10 days, 5 hours left to enroll

762 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question