[isalist] Re: wpad.dat DNS entry

Hi Periyasamy,

How are you sure array's FQDN is never resolved to VIP by RRed DNS?

Roy
  ----- Original Message ----- 
  From: Periyasamy, Raj 
  To: isalist@xxxxxxxxxxxxx 
  Sent: Friday, September 01, 2006 11:38 PM
  Subject: [isalist] Re: wpad.dat DNS entry


  You still need to keep the physical names of both array members in the DNS. 
WPAD will issue a script to the client, that will point to both the ISA servers 
by the physical name, not virtual name of NLB. When you do NETSTAT you will see 
that your client is actually talking to the physical names of the ISA and not 
the virtual name.
  HTH. 
  Regards, 
  Raj Periyasamy 
  MCSE(Messaging), CCNA 


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  From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On 
Behalf Of Roy Tsao
  Sent: Friday, September 01, 2006 11:27 AM
  To: isalist@xxxxxxxxxxxxx
  Subject: [isalist] Re: wpad.dat DNS entry


  Jim,

  I am thinking about one more RR related scenario under ISA EE (not SE), say 
after enable 
  NLB at internal interface of ISA EE array, what shall be the correct setting
  at DNS when a record is set array's FQDN -> array's VIP
     1) keep a record of each array's memember at DNS
     2) or those must be deleted
  How is client-side CARP in 1) and 2)? 
    ----- Original Message ----- 
    From: Roy Tsao 
    To: isalist@xxxxxxxxxxxxx 
    Sent: Friday, September 01, 2006 11:08 PM
    Subject: [isalist] Re: wpad.dat DNS entry


    Jim,

    You are pointing out sort of worse issue in so called double loading 
shareing using RR and 
    client-side CARP under ISA EE array, that's true! 
    However in the scenario I showed, RR is used for load-sharing among ISA 
SE...

    Dan, 
    I remembered you ever mentioned Raiwall was used in your network for NLB 
under ISA SE,
    that's the another reason I propose RR for ISA SE.
      ----- Original Message ----- 
      From: Jim Harrison 
      To: isalist@xxxxxxxxxxxxx ; isalist@xxxxxxxxxxxxx 
      Sent: Friday, September 01, 2006 9:39 PM
      Subject: [isalist] Re: wpad.dat DNS entry


      If these servers operate in an array, using RR can actually decrease your 
load-sharing across the array.
      Since we're talking about WPAD here, you *must* bear in mind that the 
script obtained from the ISA contains a list of servers by name or IP, 
depending on your configuration.

      If you try to round-robin or (worse yet), NLB these IPs, client-side CARP 
will fight with the LB mechanism.

      BTW, there's nothing wrong with multiple internal subnets.
      In fact, it can help you control segmentation better, because no DG == no 
non-local subnet & blackhole routers == no non-local subnet.

--------------------------------------------------------------------------

      From: isalist-bounce@xxxxxxxxxxxxx on behalf of Ball, Dan
      Sent: Fri 9/1/2006 4:20 AM
      To: isalist@xxxxxxxxxxxxx
      Subject: [isalist] Re: wpad.dat DNS entry


      Okay, my bad, someday I'll get those terms right.  What you say makes 
sense, it's definitely an option.



      I'm just hoping our WAN fiber goes into place soon, then I won't have to 
worry about multiple internal sub-nets anymore.




--------------------------------------------------------------------------

      From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] 
On Behalf Of Roy Tsao
      Sent: Thursday, August 31, 2006 2:25 PM
      To: isalist@xxxxxxxxxxxxx
      Subject: [isalist] Re: wpad.dat DNS entry



      Hi Dan,



      I said "Except SNAT".



      Moreover, unless special client required as SNAT like published server, 
FWC plus WPC shall be deployed to most of

      clients under ISA Firewall environment, we can maximize the benefit 
provided by ISA, right?

      So even if there is gateway at client side, most of them shall go through 
FWC or WPC connection.

      Again, I try to say the positive point of DNS round robin feature, that's 
it.



      HTH,



      Roy 

        ----- Original Message ----- 

        From: Thomas W Shinder 

        To: isalist@xxxxxxxxxxxxx 

        Sent: Friday, September 01, 2006 1:37 AM

        Subject: [isalist] Re: wpad.dat DNS entry



        I've done it in many deployments, and IIRC, that's how they do it at MS.



        Thomas W Shinder, M.D.
        Site: www.isaserver.org
        Blog: http://blogs.isaserver.org/shinder/
        Book: http://tinyurl.com/3xqb7
        MVP -- ISA Firewalls






----------------------------------------------------------------------

          From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Ball, Dan
          Sent: Thursday, August 31, 2006 12:26 PM
          To: isalist@xxxxxxxxxxxxx
          Subject: [isalist] Re: wpad.dat DNS entry

          We had briefly touched upon this topic about a year or so ago, but I 
wasn't aware that it was an actual common practice.




----------------------------------------------------------------------

          From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Thomas W Shinder
          Sent: Thursday, August 31, 2006 12:18 PM
          To: isalist@xxxxxxxxxxxxx
          Subject: [isalist] Re: wpad.dat DNS entry



          Hi Dan,



          In most secure environments you don't give the clients a default 
gateway and use the Firewall and Web proxy client configurations to enfroce 
security. So, this might work fine using RR DNS.



          Thomas W Shinder, M.D.
          Site: www.isaserver.org
          Blog: http://blogs.isaserver.org/shinder/
          Book: http://tinyurl.com/3xqb7
          MVP -- ISA Firewalls






--------------------------------------------------------------------

            From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Ball, Dan
            Sent: Thursday, August 31, 2006 11:02 AM
            To: isalist@xxxxxxxxxxxxx
            Subject: [isalist] Re: wpad.dat DNS entry

            I'd have to say no.

            -          External sites are resolved by DNS server.

            -          Resolved sites are referenced then by IP address.

            -          Since an external site is resolved to an IP that is not 
a "local" address, it resorts to using the default gateway to connect.

            -          Default gateways are entered by IP, not hostname, 
nullifying the round-robin DNS abilities.



            The exception to this might be if you use the FWC, then you might 
be able to redirect all connections via DNS entries.  You might be able to 
share the proxy address too, but that default gateway is a kicker.




--------------------------------------------------------------------

            From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Roy Tsao
            Sent: Thursday, August 31, 2006 10:00 AM
            To: isalist@xxxxxxxxxxxxx
            Subject: [isalist] Re: wpad.dat DNS entry



            Hm...



            You have two ISA SE, let say its internal interface IP address is 
192.168.0.1/24 and 192.168.0.2/24.

            You creat two a record in DNS, isa.dan.local -> 192.168.0.1   and  
isa.dan.local -> 192.168.0.2

            Then by DNS round robin, your internal client (except SNAT) would 
enjoy the connection to either

            of the ISA SE server for ounbound connection, make sense? 

              ----- Original Message ----- 

              From: Ball, Dan 

              To: isalist@xxxxxxxxxxxxx 

              Sent: Thursday, August 31, 2006 9:01 PM

              Subject: [isalist] Re: wpad.dat DNS entry



              I think that would only work on inbound connections.  You can't 
define round-robin DNS entries for someone else's server!




------------------------------------------------------------------

              From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Roy Tsao
              Sent: Thursday, August 31, 2006 8:42 AM
              To: isalist@xxxxxxxxxxxxx
              Subject: [isalist] Re: wpad.dat DNS entry



              Surely about outbound connection!

                ----- Original Message ----- 

                From: Ball, Dan 

                To: isalist@xxxxxxxxxxxxx 

                Sent: Thursday, August 31, 2006 8:34 PM

                Subject: [isalist] Re: wpad.dat DNS entry



                You referring to incoming or outgoing connections? 




----------------------------------------------------------------

                From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Roy Tsao
                Sent: Thursday, August 31, 2006 8:28 AM
                To: isalist@xxxxxxxxxxxxx
                Subject: [isalist] Re: wpad.dat DNS entry



                Dan,



                Suppose you have two external line provided by different ISP, 
normally two ISA EE is needed 

                but by using DNS round robin, you can deploy two ISA SE for 
load balancing..., that's my

                point.



                HTH,



                Roy 

                  ----- Original Message ----- 

                  From: Ball, Dan 

                  To: isalist@xxxxxxxxxxxxx 

                  Sent: Thursday, August 31, 2006 8:19 PM

                  Subject: [isalist] Re: wpad.dat DNS entry



                  No, you would still have that "one default gateway" problem.  
Besides, that feature is only for DNS entries that "you" control, not external.




--------------------------------------------------------------

                  From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Roy Tsao
                  Sent: Thursday, August 31, 2006 4:36 AM
                  To: isalist@xxxxxxxxxxxxx
                  Subject: [isalist] Re: wpad.dat DNS entry



                  Dan,



                  Your problem is due to DNS round robin feature, and it shall 
be solved by Stefaan's great 

                  guidance. 

                  On the other hand, don't you think we can utilize such round 
rodin as a good feature to

                  implement NLB to balance connection to multi external 
interface by using ISA STD version

                  only?



                  HTH,



                  Roy Tsao

                    ----- Original Message ----- 

                    From: Stefaan Pouseele 

                    To: isalist@xxxxxxxxxxxxx 

                    Sent: Thursday, August 31, 2006 4:08 PM

                    Subject: [isalist] Re: wpad.dat DNS entry



                    you might check out 
http://support.microsoft.com/?kbid=842197. 



                    HTH, 

                    Stefaan




------------------------------------------------------------

                    From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Ball, Dan
                    Sent: donderdag 31 augustus 2006 3:28
                    To: isalist@xxxxxxxxxxxxx
                    Subject: [isalist] Re: wpad.dat DNS entry

                    Good article, it sounds very similar to my scenario.  I 
already had the "enable netmask ordering" option enabled, so that is not the 
problem.  Do you think it might be because each of the 10.6.x.x subnets have a 
mask of 255.255.255.0?  








------------------------------------------------------------

                    From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Stefaan Pouseele
                    Sent: Wednesday, August 30, 2006 3:57 PM
                    To: isalist@xxxxxxxxxxxxx
                    Subject: [isalist] Re: wpad.dat DNS entry



                    Hi Dan, 



                    check out my blog 
http://blogs.isaserver.org/pouseele/2006/06/30/multi-networking-wpad-support-in-isa-2004/.
 



                    HTH, 

                    Stefaan




------------------------------------------------------------

                    From: isalist-bounce@xxxxxxxxxxxxx 
[mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Ball, Dan
                    Sent: woensdag 30 augustus 2006 21:47
                    To: isalist@xxxxxxxxxxxxx
                    Subject: [isalist] wpad.dat DNS entry

                    I'm having a serious problem here with the wpad name 
resolution.  I moved it from being sent out via DHCP to DNS per Jim's 
recommendation, which seems to have speeded up some things, but is now 
unreliable and causing problems.



                    The problem appears to be the multiple internal subnets.  
Here is a diagram of how it is laid out:



                    Internet

                        |

                    ISA Server --- Internal Network 1 (10.20.1.1)

                        |

                    Internal Network 2 (10.6.254.90)---- 10.6.8.x Subnet

                                                                   |-- 10.6.9.x 
Subnet

                                                                   |-- 
10.6.10.x Subnet

                                                                   |-- 
10.6.12.x Subnet

                                                                   |-- 
10.6.14.x Subnet

                                                                   |-- 
10.6.15.x Subnet

                        

                    I entered two Host (A) records for wpad, one for 10.20.1.1, 
and another for 10.6.254.90.  



                    Frequently I run across computers on the 10.6.x.x subnet 
where the FWC cannot automatically detect the ISA server, so I ping wpad and it 
resolves to the 10.20.1.1 address instead of the 10.6.254.90 address that it is 
supposed to get.  I try repairs and such, it keeps resolving to the wrong one.  
When I reboot the computer, it resolves to the correct IP and works properly.  
I reboot the computer several times, and it gets the correct address.  But, 
I'll hear of another computer having problems, and I'll check and it is the 
same problem.  This is not going to be pretty over the next few days as teacher 
come back to work after summer vacation.



                    What is the best way to resolve this?  Change it back to 
DHCP, customize host files, etc?  

      All mail to and from this domain is GFI-scanned.

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