list all nodes as seeds (excluding self)

[Anne Sullivan <ac...@gmail.com>]

For ease of maintenance and because we'll likely have many deployments
where the cluster size is very small (2 - 5 nodes), I'm wondering if I can
set my seed_provider list to contain all nodes except the local node's IP.
 ie) For nodes A-C
A-> B, C
B-> A, C
C-> A, B

I think my question is more or less In line with this comment, I'm
wondering if satisfying ONLY 2) is safe:
https://issues.apache.org/jira/browse/CASSANDRA-5836?focusedCommentId=13727032

Datastax docs suggest that "every node should have the same list of seeds",
and also "To prevent partitions in gossip communications, use the same list
of seed nodes in all nodes in a cluster".  I wouldn't end up with gossip
partitions in the example above, so if that's the only reason for the
recommendation of keeping the list consistent across all nodes then it
should be ok.  Reading other comments regarding the seed list /
bootstrapping, I *think* this will be ok but would appreciate
confirmation/comments.

My goal is to have all nodes auto-bootstrap.  When adding a new node, I
don't want to do 2 edits to the config file (first start without node as
seed, then add node as seed).

thanks
Anne

Re: list all nodes as seeds (excluding self)

[Robert Coli <rc...@eventbrite.com>]

On Tue, Dec 10, 2013 at 5:58 AM, Anne Sullivan <
anne.b.sullivan@alcatel-lucent.com> wrote:

>  My understanding is that a node won't auto-bootstrap if it thinks it's a
> seed node.  So when adding a new node to an existing cluster, I want to
> make sure it will auto-bootstrap, and I don't want to do 2 edits to the
> config file (first start without node as seed, then add node as seed).
>

Your input, as an operator who doesn't want to do this illogical and error
prone conf file dance, is welcome here :

https://issues.apache.org/jira/browse/CASSANDRA-5836

"Seed nodes should be able to bootstrap without manual intervention"

=Rob

Re: list all nodes as seeds (excluding self)

[Daneel Yaitskov <rt...@gmail.com>]

What is the problem to put all nodes on the seed list without any exclusion.
Constant list is the simplest solution.
You should write it once in cassandra.yaml, tar with everything you need
(cassandra, jdk) and copy as many as number of your nodes on the list.

Really 1 thing you should generate is rpc address and listen address.

I use self extracting bash archives
cat <<EOF
listen_address: $HOSTNAME
EOF


On Mon, Dec 9, 2013 at 7:32 PM, Anne Sullivan <ac...@gmail.com> wrote:

> For ease of maintenance and because we'll likely have many deployments
> where the cluster size is very small (2 - 5 nodes), I'm wondering if I can
> set my seed_provider list to contain all nodes except the local node's IP.
>  ie) For nodes A-C
> A-> B, C
> B-> A, C
> C-> A, B
>
> I think my question is more or less In line with this comment, I'm
> wondering if satisfying ONLY 2) is safe:
>
> https://issues.apache.org/jira/browse/CASSANDRA-5836?focusedCommentId=13727032
>
> Datastax docs suggest that "every node should have the same list of
> seeds", and also "To prevent partitions in gossip communications, use the
> same list of seed nodes in all nodes in a cluster".  I wouldn't end up with
> gossip partitions in the example above, so if that's the only reason for
> the recommendation of keeping the list consistent across all nodes then it
> should be ok.  Reading other comments regarding the seed list /
> bootstrapping, I *think* this will be ok but would appreciate
> confirmation/comments.
>
> My goal is to have all nodes auto-bootstrap.  When adding a new node, I
> don't want to do 2 edits to the config file (first start without node as
> seed, then add node as seed).
>
> thanks
> Anne
>
>
>


-- 
Daneel S. Yaitskov