// Admin tip: use a CNAME DNS RR as alias for services like DynDNS.com

Dynamic DNS services like DynDNS are very useful, e.g. for LAN access via VPN in combination with non-static IP addresses. But the dynamic DNS hostname is normally a subdomain of the service (e.g. example.dyndns.org) which is often hard to remember. And this name is tying yourself up to the service you are using because a change may be really annoying (you have to change documentation, inform users and stuff).

I'm always wondering why most admins don't use a simple trick to solve all these problems: Use a sub-domain of your own domain (e.g. vpn) and set a CNAME RR for it. Let it simply point to your dynamic DNS hostname:

vpn.example.com.   CNAME  example.dyndns.org.

That's all, you are be able to use vpn.example.com from now on. A sub-domain of your main address should be much easier to remember and you can switch to another dynamic DNS service whenever you want. Without any noticeable difference for a common user.

// Global DNS problems regarding the .de Top Level Domain [Update2]

Half of the Internet seems to be down today. Most sites I wanted to visit where not accessible because of a timeout.1)

First I thought the DNS server of my provider is down, this would not be the first time. But the problem still exists after switching to another, non-provider DNS server. Doing some research, it comes to light that there seems to be a serious problem regarding the whole .de-TLD caused by the DENIC root nameservers. Seriously – WTF?! 8-O 8-O

If this is true, it will be a really big problem. Should DENIC not fix it within the next hours, most .de based sites will not be reachable (at least if the provider DNS-caches are empty, common DNS A-RRs configurations got a TTL of 86400sec/1day).

Update: Yes, it is really a DENIC fail. So don't blame your provider and/or admin if your .de website is not reachable within the next hours.

Update2: DENIC released a public statement about the issue.

e.g. ping andreas-haerter.de results in ping: “unknown host andreas-haerter.de”
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