nameservers on EC2
1.Boot 2 linux servers on EC2 (we used ubuntu hardy)
2.Assign elastic IP to each of them (static IP)
3.Register a domain (eg yournameserver.com) with somebody like ukreg.com or 1and1 registrars
4.On the domain settings – create 2 host records (glue records) – ns1.yournameserver.com and ns2.yournameserver.com and point each record to each of the elastic IPs.
5.On your 2 nameserver instances – create dns zone for ns1. and ns2 respectively
6.Make ns2 a slave of ns1 (so you only have to update the records in ns1 and ns2 will update automatically) – you can if you wish add ns3… ns4.. etc etc but its not necessary unless your site is getting millions of users.
7.Boot another EC instance and install the Scalr application.
8.Create a user on ns1. called “named” that has permissions to update the dns zone records on ns1.
9.The DNS settings of the scalr application will refer to the nameservers ns1. with user “named” and password as set on ns1.
right – thats the system setup – now for the application you want to run on your farm
10.Your application for example will have the domain yourapplication.com. Register this domain and set its nameservers to your ns1. and ns2 mentioned previously.
11.You need to first create a new zone file on ns1 for yourapplication.com
12.In Scalr when asked for the application domain name – simply enter yourapplication.com – and scalr will handle the rest.
http://groups.google.com/group/scalr-discuss/web/how-to-host-your-mx-on-google
Sandeep Verma 
One thing I don’t understand is – when trying to set the nameservers to the two new elastic IPs, my registrar (EasySpace) is complaining that the elastic IPs (and indeed the FQDNs for them) are not registered nameservers and won’t allow me to set them.
I have a friend who is also having the same problem with his ‘.com’ domain registered with UK2.
In both cases, we have both master/slave servers serving the records for the domain fine (both dig fine). I’m wondering, how did you manage to get your elastic IPs ‘registered’ and added to your 1&1 CP?
In the meantime, I’ve worked around it by naming two registered nameservers and having them slave the domains from the EC2 hosts.
Could you post an example zone file from your nameserver configuration?
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