title: mongodb can't start with Invariant failure false
body: <p>I use mongodb. After stop mongod I can not start with error show in log below</p>
  
  <p>log:</p>
  
  <pre><code>...
  2015-11-18T16:42:01.017+0800 I JOURNAL  [journal writer] Journal writer thread started
  2015-11-18T16:42:01.128+0800 I NETWORK  [initandlisten] waiting for connections on port 27017
  2015-11-18T16:42:01.146+0800 I NETWORK  [initandlisten] connection accepted from 127.0.0.1:45738 #1 (1 connection now open)
  2015-11-18T16:42:01.151+0800 I NETWORK  [initandlisten] connection accepted from 127.0.0.1:45741 #2 (2 connections now open)
  2015-11-18T16:42:01.160+0800 I NETWORK  [initandlisten] connection accepted from 127.0.0.1:45743 #3 (3 connections now open)
  2015-11-18T16:42:01.165+0800 I NETWORK  [initandlisten] connection accepted from 127.0.0.1:45745 #4 (4 connections now open)
  2015-11-18T16:42:01.166+0800 I INDEX    [conn1] btree bucket corrupt? consider reindexing or running validate command
  2015-11-18T16:42:01.166+0800 I INDEX    [conn1]   klast: { : new Date(1447832163431) }
  2015-11-18T16:42:01.166+0800 I INDEX    [conn1]   key:   { : new Date(1447832226553) }
  2015-11-18T16:42:01.166+0800 I -        [conn1] Invariant failure false src/mongo/db/storage/mmap_v1/btree/btree_logic.cpp 399
  2015-11-18T16:42:01.234+0800 I CONTROL  [conn1] 
   0xf75549 0xf12271 0xef6022 0xd0fce7 0xd11d08 0xd12307 0xd12622 0xd126b7 0xd126b7 0xd126b7 0xd12bb9 0xd04c2f 0xa835eb 0x916ebe 0x917235 0x904cf0 0x9050ed 0x9a6d63 0x9a7abd 0x9a998e 0x9aa0cb 0x9acb5d 0x9cf044 0x9cffcd 0x9d0cdb 0xba223a 0xab3ba0 0x7fb86d 0xf268ab 0x7ffc1734ca51 0x7ffc15e9e93d
   ......
   mongod(_ZN5mongo15printStackTraceERSo+0x29) [0xf75549]
   mongod(_ZN5mongo10logContextEPKc+0xE1) [0xf12271]
   mongod(_ZN5mongo15invariantFailedEPKcS1_j+0xB2) [0xef6022)
   mongod(_ZN5mongo17PortMessageServer17handleIncomingMsgEPv+0x34B) [0xf268ab]
   libpthread.so.0(+0x7A51) [0x7ffc1734ca51]
   libc.so.6(clone+0x6D) [0x7ffc15e9e93d]
   -----  END BACKTRACE  -----
   2015-11-18T16:42:01.234+0800 I -        [conn1] 
   ***aborting after invariant() failure
  </code></pre>
  
  <p>I found this line in log:</p>
  
  <p><code>Invariant failure false src/mongo/db/storage/mmap_v1/btree/btree_logic.cpp 399
  2015-11-18T16:42:01.234+0800 I CONTROL  [conn1]</code></p>
  
  <p>How can I start mongod? Or if can't, how can I read data from files like *.ns *.1 *.2?</p>