Learning DNS (The Hard Way)

davorg on 2005-02-14T11:46:00

It's all very well having complete control over the DNS records for your domain, but it allows you to make all sorts of new and interesting mistakes.

Lesson the first. The right hand sign of an MX record should point to an A record. Not a CNAME record. Many modern SMTP clients handle the CNAME situation fine but you run the risk of sending all sorts of interesting error messages back to the ones who don't.

I wondered why my mail load was lighter than usual.

Corrected records are propagating as I type, but if you've sent me something important in the last three or four days and haven't had a response then you might like to resend.

---

DNS checking tools

pjf on 2005-02-15T01:45:08

G'day Davorg,

Despite having done a lot of work with registrars, and otherwise more DNS management than is probably good for me, I still discover that it's easy to make mistakes.

I can recommend that you look at:

                    http://www.dnsreport.com/

DNSreport performs a number of very useful checks, and lets you know of areas where your records may need attention. It's reduced the number of problems that escalated to me significantly.

Cheerio,

      Paul

Re:DNS checking tools

davorg on 2005-02-15T10:06:09

Excellent. That's extremely useful. Thanks for pointing it out.

Re:DNS checking tools

cynix on 2005-02-17T18:27:32

I can recommend that you look at:

http://www.dnsreport.com/

Yes, that's a nice tool. But I like http://www.zonecheck.fr/demo/ even better as gives me lots of options to tweak the tests.

See also

Aristotle on 2005-02-15T23:48:23

http://www.wlug.org.nz/DNSBestPractices
http://www.wlug.org.nz/SMTPBestPractices