Hi, 

We are seeing an issue where data that was written to the cluster is no longer 
accessible after trying to expand the size of the cluster. I will try and 
provide as much information as possible, I am just starting at with Cassandra 
and I'm not entirely sure what data is relevant.

All Cassandra nodes are 1.2.5, and each node has the same config. 

We started out moving our entire data set to a single cassandra node. This node 
was initially set up with Initial Token : 0, as well as other default settings. 
After we had gotten all the data moved over we decided to add 2 more nodes, as 
well as up the RF to 2. We also decided to start using vnodes which meant 
setting num_tokens to 256 and removing the initial token param. We then decided 
to run cassandra-shuffle as well.

During cassandra-shuffle we started to notice some rows were disappearing then 
reappearing, and other rows haven't come back at all. I decided to stop the 
shuffle and repair each node then restart the cluster, however all the data 
hasn't come back. Note that this is CONSISTENCY ALL

Here is my `nodetool status` What is weird here is the token distribution 
260-239-1. I'm not an expert but I believe it should be 256-256-256, or at 
least add up to 768.

Datacenter: 129
===============
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
--  Address       Load       Tokens  Owns   Host ID                             
  Rack
UN  10.129.196.4  371.56 GB  260     38.1%  
cde6c3be-a066-47f2-abc2-b1d78bee0d7c  196
UN  10.129.196.5  212.64 GB  239     61.5%  
2cb24510-2f89-46b2-96b9-873f8e8e50da  196
UN  10.129.196.6  256.05 GB  1       0.4%   
ce8d4ea9-8106-44b3-a2dd-c0230eb53c94  196


(http://pastebin.com/37SwNaGq)

And here is the opscenter ring view (http://imgur.com/VssmFlw)

What also weird is the token count from nodetool -h [host] info differs from 
status. 

Example:
root@cass1:~# nodetool -h cass1 info | grep Token
Token            : (invoke with -T/--tokens to see all 239 tokens)
root@cass1:~# nodetool -h cass2 info | grep Token
Token            : (invoke with -T/--tokens to see all 269 tokens)
root@cass1:~# nodetool -h cass3 info | grep Token
Token            : (invoke with -T/--tokens to see all 260 tokens)


(Full output: http://pastebin.com/2hxpArt0)

I believe it has something to do with the cluster not "seeing" all the tokens, 
but I am not sure where to continue from here. I don't believe any data was 
lost there was no power outage, and all the data should have been committed to 
disk before we added the two other nodes.

Thanks,
Nimi
nimiwaribo...@gmail.com

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