In my opinion and experience, this isn’t a real problem, since you define a 
list of seeds as the first few nodes you add to a cluster.  When would you add 
a node to an existing cluster and mark itself as a seed?  It’s neither 
practical or something you’d do by accident.   

> On Feb 23, 2018, at 10:17 AM, Jeff Jirsa <> wrote:
> On Fri, Feb 23, 2018 at 10:12 AM, Oleksandr Shulgin 
> < <>> wrote:
> On Fri, Feb 23, 2018 at 7:02 PM, Jeff Jirsa < 
> <>> wrote:
> Yes, seeds don't bootstrap.  But why?  I don't think I ever seen a 
> comprehensive explanation of this.
> The meaning of seed in the most common sense is "connect to this host, and 
> use it as the starting point for adding this node to the cluster".
> If you specify that a joining node is the seed, the implication is that it's 
> already a member of the cluster (or, alternatively, authoritative on the 
> cluster's state).  Given that implication, why would it make sense to then 
> proceed to bootstrap? By setting it as a seed, you've told it that it already 
> knows what the cluster is. 
> Well, there is certain logic in that.  However, bootstrap is about streaming 
> in the data, isn't it?  And being seed is about knowing the topology, i.e. 
> which nodes exist in the cluster.  There is actually 0 overlap of these two 
> concerns, so I don't really see why a seed node shouldn't be able to 
> bootstrap.  Would it break anything if it could, e.g. if you're explicit 
> about it and request auto_boostrap=true?
> I dont *think* it would break anything, but the more obvious answer is just 
> not to list the node as a seed if it needs to bootstrap.
> This comes up a lot, and it's certainly one of those rough operator edges 
> that we can do better with. There's no strict requirement to have all of the 
> seeds exactly the same in a cluster, so if you need to bootstrap a new seed, 
> just join it with it not a seed, then bounce it to make it think it's a seed 
> after it's joined.
> The easier answer is probably "give people a way to change seeds after 
> they're running", and it sorta exists, but it's hard to invoke intentionally. 
> We should just make that easier, and the rough edges will get a little less 
> rough.

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