Using Amazon's Elastic Cloud EC2 and Rsync to back up data files

[Matthew Gillen]

John Abreau wrote:
>> The RSA fingerprint and IP address change each time that I run the
>> script because it creates and terminates an EC2 Instance—each of which
>> has its own unique DNS name.
> 
> Each EC2 instance is getting a new server key. Perhaps you could
> create a server key for it and configure your startup script to replace
> the new server key with the one you created, so each instance would
> end up using the same server key.

Supposedly you get root on your EC2 instance, so that should be doable (have 
a post-boot script that 'cp's the server key to the right place and restarts 
sshd).

>> Another concern that I have is that the 'known-hosts' file which
>> stores the host fingerprints will become increasingly large with each
>> run of the script.
> 
> 
> You could use a dynamic DNS service so each instance will be
> accessible via a single DNS name.

Maybe.  It's possible that the IP addresses are not DHCP, and many of the 
dynamic DNS services are not free if you are using a static IP.  Good idea 
though.

Matt