EC2, too clever for me, snapshots, multiple servers, instant servers, but "release" your IP address and it all falls over ( for days ).

Dear reader, you will probably be reading this in a few days time because I have just pressed the wrong button in EC2.

It’s been an interesting lesson. Part of moving to the cloud is all the extra redundancy that you get. You feel that the incredibly powerful controls that you are given mean that in some respects you haven’t really given away control but rather gained it.

You might feel uncomfortable going for a small or new host organisation but you feel safer with the big people like Amazon EC2.

The problem is that humans are still involved and some of the services that you have been given are only on loan. In my case the fixed IP address from Amazon was only on loan and when I accidentally gave it back I couldn’t get it back again. In the on premise paradigm people had redundant power supplies, redundant drives, redundant switches but did any one worry as much about loosing an IP address whilst still with the same connectivity provider ?

Its good that its Friday ( shame it wasn’t Friday evening though ) because when you see this on Monday on Planet Lotus the link might actually work depending on your local ISP’s DNS caching. Was it a good weekend for you ?

What happened

EC2 has a great feature called an “Elastic IP Address” that allows you to have a static IP address that you can switch between EC2 instances ( servers ).

If you would like to avoid some chaos then you SHOULD NOT EVER choose to “release” your Elastic IP address for once you do it disappears and is lost forever.

This means that you need to get a new one and re-do all of your DNS A records again. This means that your site will be down for days.

When moving the IP address between instances you should use the Disassociate option below. You will notice that the Release option is greyed out.

Image:EC2, too clever for me, snapshots, multiple servers, instant servers, but "release" your IP address and it all falls over ( for days ).

However, if you have just terminated the instance that had been associated with that IP address the console ( quite logically ) looks like this

Image:EC2, too clever for me, snapshots, multiple servers, instant servers, but "release" your IP address and it all falls over ( for days ).

Now I know that the logical thing to do ( in hind sight ) would be to click the Associate button but my brain has not twigged that the Dissociate action happened automatically when the instance was terminated so I clicked the “Release Address” button and got this.

Image:EC2, too clever for me, snapshots, multiple servers, instant servers, but "release" your IP address and it all falls over ( for days ).

I really want them to change it to say this

Image:EC2, too clever for me, snapshots, multiple servers, instant servers, but "release" your IP address and it all falls over ( for days ).

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