Rabbitmq start fails

I ran into the same issue and this is what helped me.

The Mnesia files in questions were located in /var/lib/rabbitmq/.

For anyone else looking for this error rabbit,failure_during_boot,

{badmatch,  
     {error,  
      {{{function_clause,  
         [{rabbit_queue_index,journal_minus_segment1, ...

I just dealt with the same issue and what helped was going to the mnesia directories and deleting the queues and msg_store_transient directories.

From what I understand, what happens is that you end up with a bad queue db (for whatever reason -i.e. a sudden power failure, some other process touches the files) which rabbitmq can't parse and so it crashes. Once you clear the queue of messages, it works fine.