DNS n00b. Windows/Linux oddness...

Discussion in 'Networking, Telephony & Internet' started by ^catalyst, Jan 22, 2013.

  1. ^catalyst

    ^catalyst Member

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    OK.

    So.

    I'm in the process of implementing some web-based software for work. Most of that is going well. The user goes to http://<address>/rt . Now, I want that to be classy, not just some class C address. So what I want is http://<fancyname>/rt. for the sake of being informative it's apache2/rt and the last octet is .253

    The software likes all the requests formatted http://<same hostname everytime>/jkladfhladhfklajfajdfjlajfhjkladfhklasjhf

    We use a snapgear thingy which does DHCP/VPN/DNS etc. My understanding is that is uses a 'dns proxy'. So I've dived in there and set a static host with <servername>/<address>.

    Then, on my linux mint box, I can ping <servername> and it works a treat. Throw http://<servername>/rt in the browser and away she goes. I was very happy with myself.

    Then I went to show the boss didn't I? On his windows box. <servername> doesn't work in browser or ping. Doh. Entering the address manually works fine though, however rt cracks it at the user for potential xss attack. Not so good.

    So, I went and tried another linux machine, no drama! but none of the windows boxes do it!!

    I've waited 12 hours to see if it works itself out, but it hasn't.

    Am I a retard?
     
  2. TehCamel

    TehCamel Member

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    it should just work.
    the windows hosts may need a dns suffix though..

    on one of the windows clients, try command line nslookup
    and see if you can resolve it
     
  3. OP
    OP
    ^catalyst

    ^catalyst Member

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    Yeah, while dns isn't my forte I thought it should 'just-work' as well :{|

    I put 'vanbarfitzroy' in the 'domain' on the snapgear so dhcp clients are now getting dns suffix 'vanbarfitzroy'

    nslookup output :
    Code:
    C:\Users\lach-virt>nslookup
    DNS request timed out.
        timeout was 2 seconds.
    Default Server:  UnKnown
    Address:  192.168.104.1
    
    > vanserv
    Server:  UnKnown
    Address:  192.168.104.1
    
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    *** Request to UnKnown timed-out
    > vanserv.vanbarfitzroy
    Server:  UnKnown
    Address:  192.168.104.1
    
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    *** UnKnown can't find vanserv.vanbarfitzroy: Non-existent domain
    >
     
  4. drgtr

    drgtr Member

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    The obvious question is are all the Windows computer DNS settings pointing to the IP Address of this Snapgear thingy and not the ADSL modem as this snapgear thingy is your internal DNS server.
     
  5. OP
    OP
    ^catalyst

    ^catalyst Member

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    Yes, DHCP clients are getting 192.168.104.1 as the Primary DNS. The snapgear has a host-list and then DNS proxy to DNS servers provided by the external telstra connection.
     
  6. drgtr

    drgtr Member

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    perform a local dns flush on the pcs

    dos command


    ipconfig /flushdns

    and for netbios names

    nbtstat -R

    Try again. Just wondering are they holding onto the old DNS settings.
     
  7. drgtr

    drgtr Member

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    Just trying to get the basics down.

    Are the windows pcs in the same subnet as the snapgear?
    Can the windows PC ping the snapgear device.
     
  8. drgtr

    drgtr Member

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    To see if it is a connection issue between windows pc and snapgear then modify your local host file and manually put the entry in and then see if it works

    In Windows it is in C:\WINDOWS\SYSTEM32\DRIVERS\etc
     
  9. TehCamel

    TehCamel Member

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    those nslookup results suggest the dns service on the snapgear isn't responding correctly..
     
  10. OP
    OP
    ^catalyst

    ^catalyst Member

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    I think you're right.

    *everything* else works and has done for years. All machines on one subnet etc. Very simple setup. ADSL comes in to snapgear, snapgear does everything else. Pc's get addresses from snapgear.

    Unfortunately there isn't much in the way of config for the Snapgear DNS... I'll keep looking.
     
  11. Rickm

    Rickm Member

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    It's the DNS server, your nslookup proves it as suggested above.
     
  12. mwil7034

    mwil7034 Member

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    Sure you havent got a hosts file entry resolving the FQDN on the linux box to begin with? Sounds weird one OS works but not the other. :(
     
  13. mwil7034

    mwil7034 Member

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    The fact nslookup fails does seem to indicate this... hence my question above.

    Does google.com even resolve?
     
  14. OP
    OP
    ^catalyst

    ^catalyst Member

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    Yes, google.com does resolve on the windows boxes. They have full connectivity to outside, no problems.... and no I don't have any hostfile malarky going on.
     
    Last edited: Jan 22, 2013
  15. Rickm

    Rickm Member

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    can you flush dns, and show us an nslookup result searching for google.com ?
     
  16. OP
    OP
    ^catalyst

    ^catalyst Member

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    Some shit is wrong here. Some shit is WRONG.

    Code:
    C:\Windows\system32>ipconfig /flushdns
    
    Windows IP Configuration
    
    Successfully flushed the DNS Resolver Cache.
    
    C:\Windows\system32>nbtstat -R
        Successful purge and preload of the NBT Remote Cache Name Table.
    
    C:\Windows\system32>nslookup
    DNS request timed out.
        timeout was 2 seconds.
    Default Server:  UnKnown
    Address:  192.168.104.1
    
    > vanserv
    Server:  UnKnown
    Address:  192.168.104.1
    
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    *** Request to UnKnown timed-out
    > vanserv.vanbarfitzroy
    Server:  UnKnown
    Address:  192.168.104.1
    
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    *** Request to UnKnown timed-out
    > nslookup vanbar.com.au
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    Server:  vanbar.com.au
    Address:  203.57.155.144
    
    DNS request timed out.
        timeout was 2 seconds.
    DNS request timed out.
        timeout was 2 seconds.
    *** Request to vanbar.com.au timed-out
     
  17. OP
    OP
    ^catalyst

    ^catalyst Member

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    So that was from a VM. Went and tested some of the machines out on the showroom floor and got :

    Code:
    DNS request timed out.
    timeout was 2 seconds.
    Default Server:  UnKnown
    Address:  192.168.104.1
    > vanserv
    Server:  UnKnown
    Address:  192.168.104.1
    Non-authoritative answer:
    DNS request timed out.
    timeout was 2 seconds.
    Name:    vanserv
    Address:  192.168.104.253
    But then it can't ping. I have a feeling, and that is all it is, that one of the DNS servers in the snapgear is not good.

    Hrmm.

    Even more baffling, if I do a ping from the snapgear web interface to 'vanserv' it works a treat.

    hair --> out.
     
    Last edited: Jan 22, 2013
  18. Rickm

    Rickm Member

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    Get into the snapgear and check the config on there, Also is there a secondary DNS server assigned via DHCP ?
     
  19. drgtr

    drgtr Member

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    Hey catalyst you dont have any Windows server there?
    Just set up a dns server on another server or a linux box.

    End of the day you will still achieve the result and show the boss what you wanted to do and then test the snapgear on the side in your own time.
     
  20. OP
    OP
    ^catalyst

    ^catalyst Member

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    Yeah I'm thinking that is the go mate, what I might do is setup DNS on the RT box, get it to forward the requests to google dns or something and list it as a secondary DNS on the snapgear.

    The snapgear is discontinued and I'd ultimately like to decommission it for something newer / better thought out.
     

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