TurnKey Linux Virtual Appliance Library

Hub DNS delay problem

After first installation a couple of days ago, I could connect to my hub tklapp.com domain redmine appliance (otagongs.tklapp.com) with no problem by using the hostname (browser, ssh). However, since then, if I stop/start the appliance, or reboot after updating, the hostname does not resolve, and I can only connect with the IP address - browser coughs up the following:

"TKLAPP.com The site you are looking for is currently not available. What is TKLAPP.com? it's a free dynamic DNS (DynDNS) service provided by the TurnKey Hub. It includes a simple to use web interface as well as a powerful API."

hubdns-info and hubdns-update show the correct hostname and IP address (both match that listed in the Hub dashboard). A "hubdns-init --force" does not fix it.

However, eventually, after between 30 minutes and a few hours - today it took about three hours - the hostname *does* start resolving again. I would be grateful for any advice as to what isn't working quite as it should be here, as a few hours is a bit too long for DNS propagation for my liking.

Regards, Aaron.

Update on Hub DNS delay

Browsing to the tklapp.com hostname began working some time after I switched to Google's DNS servers on my client  - I switched back to my University's dynamically assigned DNS servers,  and I can no longer connect by using the hostname again (IP is fine).

Aaron.

Jeremy's picture

One of the inherant problems with dynamic IPs

Basically the propagation of your IP by 3rd party DNS providers (such as ISPs or the DNS provided by your Uni) is beyond your control.

So if you don't wish to use a faster external DNS provider (like google) and/or it's important to you for others to be able to contact the domain regardless of their DNS provider you probably need to consider buying an elastic IP which you can assign to your appliance. Then the IP won't change and DNS becomes less of an issue.

Thanks Jeremy...

advice much appreciated. Google's DNS servers still took 1-2 hours, which made me wonder if the slow-down was from the hub to the outside world in general, rather than certain DNS providers. On campus, I've decided to use both Google's and our Uni DNS servers. If DNS propagation time remains an issue, then I'll certainly look into your elastic ip suggestion.

Aaron

Jeremy's picture

I've experienced slow propgation myself...

But I haven't gone any further to test actually where or why it is slow... I have always just assumed that it is a third party problem. Amazon says this:

Q: How quickly will changes I make to my DNS settings on Amazon Route 53 propagate globally?    
A: Amazon Route 53 is designed to propagate updates you make to your DNS records to its world-wide network of authoritative DNS servers within 60 seconds under normal conditions. A change is successfully propagated world-wide when the API call returns an INSYNC status listing.      Note that caching DNS resolvers are outside the control of the Amazon Route 53 service and will cache your resource record sets according to their time to live (TTL). The INSYNC or PENDING status of a change refers only to the state of Route 53’s authoritative DNS servers.

I just had a quick google to see if AWS nameserver IPs are listed somewhere (so we could try connecting direct to them...) but I can't find them listed!? It seems that Amazon don't give them out like most DNS providers.

Post new comment

The content of this field is kept private and will not be shown publicly. If you have a Gravatar account, used to display your avatar.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Allowed HTML tags: <a> <p> <span> <div> <h1> <h2> <h3> <h4> <h5> <h6> <img> <map> <area> <hr> <br> <br /> <ul> <ol> <li> <dl> <dt> <dd> <table> <tr> <td> <em> <b> <u> <i> <strong> <font> <del> <ins> <sub> <sup> <quote> <blockquote> <pre> <address> <code> <cite> <strike> <caption>

More information about formatting options

Leave this field empty. It's part of a security mechanism.
(Dear spammers: moderators are notified of all new posts. Spam is deleted immediately)