While I haven't configured it for multi-region yet, Sasha is exactly right now how amzon's DNS works (returning private vs. public IP depending on if the machine is local to the region or not). For extra fun, now that Route53 exists you can (somewhat trivially) map and dynamically maintain all EC2 instances to stable DNS names (but make sure to use CNAMEs to get the DNS magic!). E.g. cassandra1.somethinghardtoguess.ec2.yourdomain.com -> weird.ec2.public.dns.name
I'd drop in the somethinghardtoguess myself given Route53 can expose your internal network topology if someone can guess the DNS name. will On Wed, Apr 27, 2011 at 8:15 AM, Sasha Dolgy <sdo...@gmail.com> wrote: > Hi, > > If I understand you correctly, you are trying to get a private ip in > us-east speaking to the private ip in us-west. to make your life > easier, configure your nodes to use hostname of the server. if it's > in a different region, it will use the public ip (ec2 dns will handle > this for you) and if it's in the same region, it will use the private > ip. this way you can stop worrying about if you are using the public > or private ip to communicate with another node. let the aws dns do > the work for you. > > just make sure you are using v0.8 with SSL turned on and have the > appropriate security group definitions ... > > -sasha > > > > On Wed, Apr 27, 2011 at 1:55 PM, pankajsoni0126 > <pankajsoni0...@gmail.com> wrote: > > I have been trying to deploy Cassandra cluster across regions and for > that I > > posted this "IP address resolution in MultiDC setup". > > > > But when it is to get nodes talking to each other on different regions > say, > > us-east and us-west over private IP's of EC2 nodes I am facing problems. > > > > I am assuming if Cassandra is built for multi-DC setup it should be > easily > > deployed with node1's DC1's public IP listed as seed in all nodes in DC2 > and > > to gain idea about network topology? I have hit a dud for deployment in > such > > scenario. > > > > Or is it there any way possible to use Private IP's for such a scenario > in > > EC2, as Public Ip are less secure and costly? > -- Will Oberman Civic Science, Inc. 3030 Penn Avenue., First Floor Pittsburgh, PA 15201 (M) 412-480-7835 (E) ober...@civicscience.com