Re: Splitting 2-datacenter cluster into two clusters

2019-07-11 Thread Voytek Jarnot
Thank you for the very in-depth reply. Thinking more about it, I think in my case I'm safe with keeping the cluster name. It actually took a ton of firewall work to get these DCs talking to each other in the first place, so I'm not too concerned about undoing that and having future accidental cont

Re: Splitting 2-datacenter cluster into two clusters

2019-07-11 Thread Jeff Jirsa
Let's talk about the challenges, then talk about the strategy we'll use to do this. The logic cassandra uses to identify the rest of it's cluster comes down to ~3 things: - Cluster name (in yaml and system.local) - Seeds in your seed provider (probably a list of IPs in the yaml) - The known peers

Re: Splitting 2-datacenter cluster into two clusters

2019-07-11 Thread Voytek Jarnot
Premature send, apologies. At minimum, I see the following needing to happen: dc2: update cluster name in system.local cassandra.yaml in dc2: cluster_name: change to new cluster name seeds: change to point at a couple of local nodes system_auth, system_distributed, system_traces, and

Re: Splitting 2-datacenter cluster into two clusters

2019-07-11 Thread Oleksandr Shulgin
On Thu, Jul 11, 2019 at 5:04 PM Voytek Jarnot wrote: > My google-fu is failing me this morning. I'm looking for any tips on > splitting a 2 DC cluster into two separate clusters. I see a lot of docs > about decomissioning a datacenter, but not much in the way of disconnecting > datacenters into i

Splitting 2-datacenter cluster into two clusters

2019-07-11 Thread Voytek Jarnot
My google-fu is failing me this morning. I'm looking for any tips on splitting a 2 DC cluster into two separate clusters. I see a lot of docs about decomissioning a datacenter, but not much in the way of disconnecting datacenters into individual clusters, but keeping each one as-is data-wise (aside