RE: [load balancing] DNS lookup

From: Jose Vitor Barreiro <Vitor.BarreiroIZZATcompta.pt>
Date: Tue Jan 04 2005 - 09:16:28 EST

Thank you, that is exactly what I looked for

 

Regards

 

Vitor Barreiro

 

  _____

From: Barrett, John [mailto:John.Barrett@FMR.COM]
Sent: terça-feira, 4 de Janeiro de 2005 13:20
To: lb-l@vegan.net
Subject: RE: [load balancing] DNS lookup

 

Ok the client types that into his browser.

 

1. The client requests the IP of wwwuu.xpto.com from it's Name Server (the ISP).

2. If the ISP (assume it doesn't) doesn't have the name in it's lookup tables the

3. ISP's name server resolves the domain xpto.com from the root name servers who return the IP of the name server that is responsible for giving out xpto.com's IP addresses (authoritative).

4. The ISP's name server then requests wwwuu.xpto.com from the authoritative name server who in turn gives it an IP.

5. The ISP's name server gives that IP address back to the client who in turn uses it to go to the secure website on port 998.

 

If the name wwwuu.xpto.com is really a cname for another delegated name (wwwuu.xpto.com really is wwwuu.loadbalanced.xpto.com and that is handled by a different name server) it takes a few more steps but the principle is the same. I don't want to confuse that issue since I don't think that is what you are asking about.

 

The https and the port number have NO meaning when it comes to DNS lookups. (I think this is the real question you are asking)

 

-John

        -----Original Message-----
        From: Jose Vitor Barreiro [mailto:Vitor.Barreiro@compta.pt]
        Sent: Tuesday, January 04, 2005 4:55 AM
        To: lb-l@vegan.net
        Subject: [load balancing] DNS lookup

        What happens in a situation with a link like that?

         

        https://wwwuu.xpto.com:998/

         

        What will be the sequence?

         

        1. it looks to the domain xpto.com
        2. ??????????????

        3. ????????

         

         

         

         

        Regards

         

        Vitor Barreiro

         

        
        
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Received on Tue Jan 4 10:19:18 2005

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