node replacement failed

2018-09-08 Thread onmstester onmstester
Hi, Cluster Spec: 30 nodes RF = 2 NetworkTopologyStrategy GossipingPropertyFileSnitch + rack aware Suddenly i lost all disks of cassandar-data on one of my racks, after replacing the disks, tried to replace the nodes with same ip using this: https://blog.alteroot.org/articles/2014-03-12/replace

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread Oleksandr Shulgin
On Sat, 8 Sep 2018, 19:00 Jeff Jirsa, wrote: > Virtual nodes accomplish two primary goals > > 1) it makes it easier to gradually add/remove capacity to your cluster by > distributing the new host capacity around the ring in smaller increments > > 2) it increases the number of sources for streamin

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread onmstester onmstester
Thanks Jeff, You mean that with RF=2, num_tokens = 256 and having less than 256 nodes i should not worry about data distribution? Sent using Zoho Mail On Sat, 08 Sep 2018 21:30:28 +0430 Jeff Jirsa wrote Virtual nodes accomplish two primary goals 1) it makes it easier to gradually add

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread Jeff Jirsa
Virtual nodes accomplish two primary goals 1) it makes it easier to gradually add/remove capacity to your cluster by distributing the new host capacity around the ring in smaller increments 2) it increases the number of sources for streaming, which speeds up bootstrap and decommission Whether

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread Jonathan Haddad
> I wonder why not setting it to all the way down to 1 then? What's the key difference once you have so few vnodes? 4 tokens lets you have balanced clusters when they're small and imposes very little overhead when they get big. Using multiple tokens let's multiple nodes stream data to the new nod

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread Jonathan Haddad
Keep using whatever settings you've been using. I'd still use allocate tokens for keyspace but it probably won't make much of a difference with 256 tokens. On Sat, Sep 8, 2018 at 10:40 AM onmstester onmstester wrote: > Thanks Jon, > But i never concerned about num_tokens config before, because

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread Oleksandr Shulgin
On Sat, 8 Sep 2018, 14:47 Jonathan Haddad, wrote: > 256 tokens is a pretty terrible default setting especially post 3.0. I > recommend folks use 4 tokens for new clusters, > I wonder why not setting it to all the way down to 1 then? What's the key difference once you have so few vnodes? with s

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread onmstester onmstester
Thanks Jon, But i never concerned about num_tokens config before, because no official cluster setup documents (on datastax:  https://docs.datastax.com/en/cassandra/3.0/cassandra/initialize/initSingleDS.html or other blogs) warned us-beginners to be concerned about it. I always setup my clusters

Re: [EXTERNAL] Re: adding multiple node to a cluster, cleanup and num_tokens

2018-09-08 Thread Jonathan Haddad
256 tokens is a pretty terrible default setting especially post 3.0. I recommend folks use 4 tokens for new clusters, with some caveats. When you fire up a cluster, there's no way to make the initial tokens be distributed evenly, you'll get random ones. You'll want to set them explicitly using: