[CASSANDRA-15337] Document usage of Ec2Snitch for multiple regions cluster

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.0-alpha4, 4.0
• Component/s: Documentation/Website
• Labels: pull-request-available
• Change Category: Semantic
• Complexity: Low Hanging Fruit
• Platform: All

Source Control Link

https://github.com/apache/cassandra/commit/03424b4fd728cb3e97be30117a03532f37459858

Test and Documentation Plan

CI

• Assignee: Serban Teodorescu Assign to me
• Reporter: Serban Teodorescu

Authors

Serban Teodorescu

Reviewers

Jon Haddad

• Created: 27/Sep/19 16:21
• Updated: 16/Mar/22 13:15
• Resolved: 30/Mar/20 17:58

Description

Ec2MultiRegionSnitch was (probably) done because it was not possible in AWS to have intra-region VPC peering. This changed pin 2017, see AWS announcement (and extended with 9 more regions in 2018, see link):

Inter-Region VPC Peering allows VPC resources like EC2 instances[...] running in different AWS regions to communicate with each other using private IP addresses, without requiring gateways, VPN connections or separate network appliances.

Since the datacenter/rack names are loaded in Ec2Snitch using AWS API there is no reason why this snitch would not work in a multi-datacenter setup. I tested and used this in a production environment. So the documentation should be changed to include this usage.

Proposed change: https://github.com/apache/cassandra/compare/trunk...serban21:15337-trunk

Issue Links

• links to: GitHub Pull Request #494