title: Heroku code=H10 desc="App crashed" - Can't figure out why it's crashing
body: <p>I've been searching around on this one for a while and can't find anything that seems to be applicable in my situation. I've been staring at these logs and I can't see what the problem is. </p>
  
  <p>This has happened during deployments before, but always seemed to resolve itself. Now this just happened on its own (no deployment) and I can't get out of it. Tried reverting back to a previous version of the app, but it appears I'm stuck. I've reset the dyno and have also done a rake db:migrate.</p>
  
  <p>There are some repetitive things in the log, but I just don't know what to read out of them. Anybody have any idea where the problem is? Any guidance would be greatly appreciated. See the logs below.</p>
  
  <pre><code>Jun 18 15:51:54 snapclass-production app/heroku-postgres:  source=HEROKU_POSTGRESQL_WHITE measure.current_transaction=1077 measure.db_size=6153016bytes measure.tables=0 measure.active-connections=3 measure.waiting-connections=0 measure.index-cache-hit-rate=0.99981 measure.table-cache-hit-rate=0.99349
  Jun 18 15:52:06 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="46.165.195.139" dyno= connect= service= status=503 bytes= 
  Jun 18 15:52:07 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="178.255.152.2" dyno= connect= service= status=503 bytes= 
  Jun 18 15:52:12 snapclass-production app/postgres:  [47-1]  [] LOG:  checkpoint starting: time 
  Jun 18 15:52:13 snapclass-production app/postgres:  [48-1]  [] LOG:  checkpoint complete: wrote 0 buffers (0.0%); 0 transaction log file(s) added, 0 removed, 0 recycled; write=0.000 s, sync=0.000 s, total=0.334 s; sync files=0, longest=0.000 s, average=0.000 s 
  Jun 18 15:52:51 snapclass-production app/heroku-postgres:  source=HEROKU_POSTGRESQL_WHITE measure.current_transaction=1077 measure.db_size=6153016bytes measure.tables=0 measure.active-connections=3 measure.waiting-connections=0 measure.index-cache-hit-rate=0.99994 measure.table-cache-hit-rate=0.99997 
  Jun 18 15:53:06 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="95.141.32.46" dyno= connect= service= status=503 bytes= 
  Jun 18 15:53:48 snapclass-production app/heroku-postgres:  source=HEROKU_POSTGRESQL_WHITE measure.current_transaction=1077 measure.db_size=6153016bytes measure.tables=0 measure.active-connections=3 measure.waiting-connections=0 measure.index-cache-hit-rate=0.97826 measure.table-cache-hit-rate=0.99999 
  Jun 18 15:54:06 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="95.211.217.68" dyno= connect= service= status=503 bytes= 
  Jun 18 15:54:17 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="205.197.158.210" dyno= connect= service= status=503 bytes= 
  Jun 18 15:54:17 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/favicon.ico host=www.snapclass.com fwd="205.197.158.210" dyno= connect= service= status=503 bytes= 
  Jun 18 15:54:25 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=demosidney.snapclass.com fwd="202.46.61.33" dyno= connect= service= status=503 bytes=  
  Jun 18 15:54:44 snapclass-production heroku/web.1:  State changed from crashed to starting 
  Jun 18 15:54:44 snapclass-production app/heroku-postgres:  source=HEROKU_POSTGRESQL_WHITE measure.current_transaction=1077 measure.db_size=6153016bytes measure.tables=0 measure.active-connections=3 measure.waiting-connections=0 measure.index-cache-hit-rate=0.98897 measure.table-cache-hit-rate=0.99087 
  Jun 18 15:54:48 snapclass-production heroku/web.1:  Starting process with command `bundle exec thin start -R config.ru -e $RAILS_ENV -p 50180` 
  Jun 18 15:55:40 snapclass-production app/heroku-postgres:  source=HEROKU_POSTGRESQL_WHITE measure.current_transaction=1077 measure.db_size=6153016bytes measure.tables=0 measure.active-connections=3 measure.waiting-connections=0 measure.index-cache-hit-rate=0.99926 measure.table-cache-hit-rate=0.99996 
  Jun 18 15:55:50 snapclass-production heroku/web.1:  Error R10 (Boot timeout) -&gt; Web process failed to bind to $PORT within 60 seconds of launch 
  Jun 18 15:55:50 snapclass-production heroku/web.1:  Stopping process with SIGKILL 
  Jun 18 15:55:51 snapclass-production heroku/web.1:  Process exited with status 137 
  Jun 18 15:55:51 snapclass-production heroku/web.1:  State changed from starting to crashed 
  Jun 18 15:55:52 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=demosidney.snapclass.com fwd="119.63.193.130" dyno= connect= service= status=503 bytes= 
  Jun 18 15:55:52 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/snapclasses/sat-prep-math/register host=www.snapclass.com fwd="173.199.115.115" dyno= connect= service= status=503 bytes= 
  Jun 18 15:55:53 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="23.21.36.78" dyno= connect= service= status=503 bytes= 
  Jun 18 15:55:54 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="23.22.98.102" dyno= connect= service= status=503 bytes= 
  Jun 18 15:55:54 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="91.109.115.41" dyno= connect= service= status=503 bytes= 
  Jun 18 15:56:06 snapclass-production heroku/router:  at=error code=H10 desc="App crashed" method=GET path=/ host=www.snapclass.com fwd="174.34.224.167" dyno= connect= service= status=503 bytes= 
  </code></pre>