What are MX Records?

I was asked to explain MX records today, here it is for others as well:

MX Records, or Mail eXchange Records, is simply a line of text in a file on a DNS Server on the internet.

What it does however is VERY important. It tells other peoples mail servers where to deliver email they are sending to you.

DNS MX RecordThe first MX record (indicated by a lower number, in this example, 10 mail.domain.com.au) is known as the primary MX record. This is where email servers will try to send email first. If it fails, then it will try subsequent MX records (in this example, 20 mail.domain.com.au).

If your email server is hosted onsite on MS Small Business Server 2003 and you change ISP, you will have a new STATIC IP address assigned. Given that your MX record will be pointing to the old IP address, you won’t be getting any email arrive.

To fix this means editing the MX record to reflect the new IP address. That will involve either lodging a job with your hosting provider, or domain name registrar.

Security isn’t virtual

When speaking with some people, it has been evident that they figured virtual servers were more secure than traditional physical servers.

This quote: “I don’t want to be reverse engineering our products to find exploits or figure out signatures, fundamentally, that means we have to partner. Fortunately, there is a bunch that are happy to partner and I encourage that.” by VMware founder and chief scientist Mendel Rosenblum certainly indicates that there are security concerns (found via: VMTN Blog).

My take on it is this: not only do virtual servers have the same set of security issues as a physical server, but because there are now ‘more components in the system’ there are also more ‘points of failure’, that is, there are now more things to consider in order to make things safe.

Update 21st Sept 2007 3:32pm: see this on latest VMware bugs.

Crises conceal opportunities

Each problem has hidden in it an opportunity so powerful that it literally dwarfs the problem. The greatest success stories were created by people who recognized a problem and turned it into an opportunity.” – Joe Sugarman

I was sent this quote Tuesday this week. It is appropriate on many levels, but particularly so with regard to this web site.

You see, my database, which contains all my blog posts since I can’t remember when was miraculously destroyed. Along with it’s backups. That to me is a CRISIS.

Note to self: paranoia is healthy.

I first began blogging shortly after Chris Pirillo recommended using ‘BLOG’, a windows app that would do scheduled ftp uploads to a web site. I became a Textpattern fan, then switched to WordPress. My database contained all my posts from Textpattern and WordPress, and a whole bunch more.

But as the quote (and title) suggest, crises conceal opportunities. The opportunity here is a fresh start. No ties. A new commitment.

So, here begins not a new chapter, but a new book, the old one is no longer in print.