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Am moving a Win2003 server onto Amazon. I'd like to build it on the On Demand instance first, then if all goes well, move to a Reserved.

Question: Is there any way to move from On Demand to Reserved, or will I have to manually rebuild the machine again.

Its not an easy build and I don't want to have to do it again :-)

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"Its not an easy build and I don't want to have to do it again :-)" You're in for a world of hurt if you can't rebuild your instance. It will at some point crash in EC2 i can almost guarantee it will happen. Make sure you have a backup to easily recover from a failure. – bwight Apr 5 '12 at 17:18
Thanks for the heads up. I am documenting my build as I go. Whats your strategy for recovering from on a non EBS backed route, and will have important data and legacy db (MSDE) on the VM. – Dave Mateer Apr 5 '12 at 17:56
I generally have everything backed up in S3. I have a non-interactive script to start the instance from the latest backup so in the event of a failure i just execute a command and its up in ~3 min. In most cases the servers are on loadbalancers and recovery is automated because of the autoscaling group and loadbalancer checks. – bwight Apr 5 '12 at 19:43
up vote 5 down vote accepted

The whole on-demand vs. reserved instance thing is really just a matter of how you're billed by Amazon. The actual EC2 instances themselves are exactly the same.

Just purchase a reserved instance in the same AZ as your server is in currently, and your billing will be automatically changed to reflect the reserved rates.

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+1 for this. I was hugely confused by this the first time. Wish Amazon had something in the console saying something like "this reserved instance is currently being filled by instance i-29304293" – ceejayoz Apr 5 '12 at 15:40
Amazon seems to have their own little ecosystem for terminology and functionality...makes their documentation a little sketchy to follow. Annoying. – Bart Silverstrim Apr 5 '12 at 15:44
So, You saying that we need to launch another instance and have two instead one in order to get billed as Reserved one on the first one? – medina Sep 24 '14 at 0:46
No, if you reserve an instance, you get credit for it if you have an instance running that matches the reservation criteria. – EEAA Sep 24 '14 at 1:25

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