
Ask HN: Vultr resolving non-existent domains? - ezequiel-garzon
Hello, everyone! By chance, I happened to notice that my vultr server, <i>and many new ones deployed solely to test this</i>, resolve non-existent domains <i>as long as the hostname and label end in some TLD</i> (tested .com, .net and .org).  This issue does <i>not</i> happen for dotless or blank hostnames.<p>For instance:<p><pre><code>    $ ping sjdisdji.net
    PING sjdisdji.net.net (34.250.90.28): 56 data bytes
    $ ping doasidjaoidja8dy78y7ahduh.org
    PING doasidjaoidja8dy78y7ahduh.org.net (23.23.86.44): 56 data bytes
</code></pre>
The seemingly random resolution also happens with some CC TLDs, such as uk, fr, ar. Depending on the server it may or may not resolve .com or .org. It happens at least with OpenBSD 6.4, Ubuntu 18.10, and at least choosing London or Amsterdam.<p>I reported this (OTH-21BCZ) and was pretty disappointed with their response. First they asked me whether the issue persisted upon changing `&#x2F;etc&#x2F;reolv.conf` to<p><pre><code>    nameserver 8.8.8.8
    nameserver 8.8.4.4
 </code></pre>
It did, and their conclusion was that &quot;This is an issue with software running on your instance and not the infrastructure. I have been unable to reproduce this issue on my end on my own instances.&quot; Just to be clear, I tried this all on brand new deploys, with <i>nothing</i> on them, so I can&#x27;t conceive how this could be &quot;an issue with software running on my instance&quot;...<p>Can you guys check if you see the same thing? If so, please let me know your location and OS.<p>Thank you very much in advance!
======
anonymousiam
Who is your ISP? Are they redirecting the above google DNS servers to their
own? This would be trivial with just a few routing rules.

~~~
ezequiel-garzon
My ISP is actually a cell phone carrier in Spain, but I should point out these
pings are performed via ssh in the vultr servers. How would my ISP be relevant
to this issue?

------
ezequiel-garzon
Update: I left the issue open a couple days and the Vultr support team has
said they were able to reproduce the issue under some circumstances and they
will look into it. Now I feel more sane!

------
wahern
What's in /etc/resolv.conf?

~~~
ezequiel-garzon
Originally

    
    
       # Generated by vio0 dhclient
        nameserver 108.61.10.10
        lookup file bind
    

Then I tried

    
    
        nameserver 8.8.8.8
        nameserver 8.8.4.4
    

and

    
    
        nameserver 8.8.8.8
        nameserver 8.8.4.4
        lookup file bind
    

These changes I only tried on my stable server, running OpenBSD 6.4.

~~~
wahern
Here's what I get from vultr's Santa Clara location:

    
    
      $ host sjdisdji.net 108.61.10.10                  
      Using domain server:
      Name: 108.61.10.10
      Address: 108.61.10.10#53
      Aliases: 
    
      Host sjdisdji.net not found: 3(NXDOMAIN)
    
      $ host doasidjaoidja8dy78y7ahduh.org 108.61.10.10    
      Using domain server:
      Name: 108.61.10.10
      Address: 108.61.10.10#53
      Aliases: 
    
      Host doasidjaoidja8dy78y7ahduh.org not found: 3(NXDOMAIN)

~~~
ezequiel-garzon
Thanks a lot for replying, and for taking the time. Is your server’s hostname
a FQDN?

Edit: I just checked, it doesn’t do this with host, but it does with ping.
What about ping?

