I am new in this, so forgive my beginner question. I have an aws account which is currently in us-west-2c. It has a instance running, and also a couple of volumes which i made. I have multiple backups of my instance in amazon-s3 created by the ec2-create-snapshot command. If my current ec2 server crashes cause of some reason and i cannot log in to the aws account, can I restore the data from the snapshot in s3 in another aws account in another region? If so, how can I do it in CLI?
Rather than creating just a snapshot of a single volume, you can create an AMI which also includes some instance configuration details (e.g., include all related volumes, kernel configs, etc).
Both AMIs and Snapshots can be shared with multiple accounts (http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/sharingamis-explicit.html and http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-modifying-snapshot-permissions.html, respectively)
However, if you're concerned about losing a whole region, you can use the cross region copy features for both AMIs and Snapshots. There's no reason to cross account boundaries for DR purposes. (AMI:http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/CopyingAMIs.html, Snapshot: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-modifying-snapshot-permissions.html)