Hello, Please note that DataStax has updated the documentation for replacing a seed node. The new docs outline a simplified process to help avoid the confusion on this topic.
http://www.datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_replace_seed_node.html Jonathan [image: datastax_logo.png] Jonathan Lacefield Solution Architect | (404) 822 3487 | jlacefi...@datastax.com [image: linkedin.png] <http://www.linkedin.com/in/jlacefield/> [image: facebook.png] <https://www.facebook.com/datastax> [image: twitter.png] <https://twitter.com/datastax> [image: g+.png] <https://plus.google.com/+Datastax/about> <http://feeds.feedburner.com/datastax> <https://github.com/datastax/> On Tue, Feb 17, 2015 at 8:04 PM, Robert Coli <rc...@eventbrite.com> wrote: > On Tue, Feb 17, 2015 at 2:25 PM, <sean_r_dur...@homedepot.com> wrote: > >> SimpleSnitch is not rack aware. You would want to choose seed nodes and >> then not change them. Seed nodes apparently don’t bootstrap. >> > > No one seems to know what a "seed node" actually *is*, but "seed nodes" > can in fact bootstrap. They just have to temporarily forget to tell > themselves that they are a seed node while bootstrapping, and then other > nodes will still gossip to it as a seed once it comes up, even though it > doesn't consider itself a seed. > > > https://issues.apache.org/jira/browse/CASSANDRA-5836?focusedCommentId=13727032&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13727032 > " > > Replacing a seed node is a very common operation, and this best practice > is confusing/poorly documented. There are regular contacts to > #cassandra/cassandra-user@ where people ask how to replace a seed node, > and are confused by the answer. The workaround also means that, if you do > not restart your node after bootstrapping it (and changing the conf file > back to indicate to itself that it is a seed) the node runs until next > restart without any understanding that it is a seed node. > > Being a seed node appears to mean two things : > > 1) I have myself as an entry in my own seed list, so I know that I am a > seed. > 2) Other nodes have me in their seed list, so they consider me a seed. > > The current code checks for 1) and refuses to bootstrap. The workaround is > to remove the 1) state temporarily. But if it is unsafe to bootstrap a seed > node because of either 1) or 2), the workaround is unsafe. > > Can you explicate the special cases here? I sincerely would like to > understand why the code tries to prevent "a seed" from bootstrapping when > one can clearly, and apparently safely, bootstrap "a seed". > > " > > > Unfortunately, there has been no answer. > > > =Rob > > > >
