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https://issues.apache.org/jira/browse/CASSANDRA-19580?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17839924#comment-17839924
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Brandon Williams commented on CASSANDRA-19580:
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The purpose of hibernate is to have other nodes ignore the dead state, 
otherwise they will see the old node alive and just mark it back UP.

If you have internode_compression=dc then replacement with the same IP will not 
work, you need to use a different IP because the compression has already been 
negotiated on the other nodes.



> Unable to contact any seeds with node in hibernate status
> ---------------------------------------------------------
>
>                 Key: CASSANDRA-19580
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-19580
>             Project: Cassandra
>          Issue Type: Bug
>            Reporter: Cameron Zemek
>            Priority: Normal
>
> We have customer running into the error 'Unable to contact any seeds!' . I 
> have been able to reproduce this issue if I kill Cassandra as its joining 
> which will put the node into hibernate status. Once a node is in hibernate it 
> will no longer receive any SYN messages from other nodes during startup and 
> as it sends only itself as digest in outbound SYN messages it never receives 
> any states in any of the ACK replies. So once it gets to the check 
> `seenAnySeed` in it fails as the endpointStateMap is empty.
>  
> A workaround is copying the system.peers table from other node but this is 
> less than ideal. I tested modifying maybeGossipToSeed as follows:
> {code:java}
>     /* Possibly gossip to a seed for facilitating partition healing */
>     private void maybeGossipToSeed(MessageOut<GossipDigestSyn> prod)
>     {
>         int size = seeds.size();
>         if (size > 0)
>         {
>             if (size == 1 && 
> seeds.contains(FBUtilities.getBroadcastAddress()))
>             {
>                 return;
>             }
>             if (liveEndpoints.size() == 0)
>             {
>                 List<GossipDigest> gDigests = prod.payload.gDigests;
>                 if (gDigests.size() == 1 && 
> gDigests.get(0).endpoint.equals(FBUtilities.getBroadcastAddress()))
>                 {
>                     gDigests = new ArrayList<GossipDigest>();
>                     GossipDigestSyn digestSynMessage = new 
> GossipDigestSyn(DatabaseDescriptor.getClusterName(),
>                                                                            
> DatabaseDescriptor.getPartitionerName(),
>                                                                            
> gDigests);
>                     MessageOut<GossipDigestSyn> message = new 
> MessageOut<GossipDigestSyn>(MessagingService.Verb.GOSSIP_DIGEST_SYN,
>                                                                               
>             digestSynMessage,
>                                                                               
>             GossipDigestSyn.serializer);
>                     sendGossip(message, seeds);
>                 }
>                 else
>                 {
>                     sendGossip(prod, seeds);
>                 }
>             }
>             else
>             {
>                 /* Gossip with the seed with some probability. */
>                 double probability = seeds.size() / (double) 
> (liveEndpoints.size() + unreachableEndpoints.size());
>                 double randDbl = random.nextDouble();
>                 if (randDbl <= probability)
>                     sendGossip(prod, seeds);
>             }
>         }
>     }
>  {code}
> Only problem is this is the same as SYN from shadow round. It does resolve 
> the issue however as then receive an ACK with all the states.



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