Re: [akka-user] Cluster and the order of seed-nodes

[Endre Varga]

Hi Anders,

From the docs (http://doc.akka.io/docs/akka/2.3.11/scala/cluster-usage.html#Joining_to_Seed_Nodes):

The seed nodes can be started in any order and it is not necessary to have all seed nodes running, but the node configured as the first element in the seed-nodes configuration list must be started when initially starting a cluster, otherwise the other seed-nodes will not become initialized and no other node can join the cluster. The reason for the special first seed node is to avoid forming separated islands when starting from an empty cluster. It is quickest to start all configured seed nodes at the same time (order doesn't matter), otherwise it can take up to the configured seed-node-timeout until the nodes can join.

Once more than two seed nodes have been started it is no problem to shut down the first seed node. If the first seed node is restarted, it will first try to join the other seed nodes in the existing cluster.

On Fri, May 29, 2015 at 3:10 PM, Anders Båtstrand <ande...@gmail.com> wrote:

Dear group

I have a cluster, and all nodes have a list of all the other nodes in config element akka.cluster.seed-nodes. This list is the same on all nodes.

I am experiencing that only the node that is first in the list, is able to join itself upon startup. If any of the other nodes start up while the first node is down, they are unable to form a cluster.

I can read from the scala code (if I read it correct), that the first element of the list get a different treatment. Is this correct? What is the significance of the order of seed-nodes?

I am getting around the error by configuring the nodes individually, each with it self as the first seed node...

Best regards,

Anders Båtstrand

--
>>>>>>>>>> Read the docs: http://akka.io/docs/
>>>>>>>>>> Check the FAQ: http://doc.akka.io/docs/akka/current/additional/faq.html
>>>>>>>>>> Search the archives: https://groups.google.com/group/akka-user
---
You received this message because you are subscribed to the Google Groups "Akka User List" group.
To unsubscribe from this group and stop receiving emails from it, send an email to akka-user+...@googlegroups.com.
To post to this group, send email to akka...@googlegroups.com.
Visit this group at http://groups.google.com/group/akka-user.
For more options, visit https://groups.google.com/d/optout.

[Anders Båtstrand]

Thank you!

My mistake, it is written very clearly in the docs.

Best regards,

Anders