This is the second time this has happened to me.
Running on a Ubuntu 16.04 box.
I have 2 collections and 2 dashboards named Financial and Grid.
2 times I have issued the Linux reboot command and the Grid collection and dashboard are gone.
Is this common ? Is there anyway to recover ?
Metabase log after reboot:
Jun 25 14:31:07 INFO metabase.util :: Loading Metabase…
Jun 25 14:31:14 INFO metabase.util.encryption :: DB details encryption is DISABLED for this Metabase instance. 
See http://www.metabase.com/docs/latest/operations-guide/start.html#encrypting-your-database-connection-details-at-rest for more information.
Jun 25 14:31:22 INFO metabase.core :: Starting Metabase in STANDALONE mode
Jun 25 14:31:22 INFO metabase.core :: Launching Embedded Jetty Webserver with config:
{:port 3000}
Jun 25 14:31:22 INFO metabase.core :: Starting Metabase version v0.29.3 (0de4585 release-0.29.3) …
Jun 25 14:31:22 INFO metabase.core :: System timezone is ‘Etc/UTC’ …
Jun 25 14:31:23 INFO metabase.core :: Setting up and migrating Metabase DB. Please sit tight, this may take a minute…
Jun 25 14:31:23 INFO metabase.db :: Verifying h2 Database Connection …
Jun 25 14:31:24 INFO metabase.db :: Verify Database Connection … 
Jun 25 14:31:24 INFO metabase.db :: Running Database Migrations…
Jun 25 14:31:24 INFO metabase.db :: Setting up Liquibase…
Jun 25 14:31:24 INFO metabase.db :: Liquibase is ready.
Jun 25 14:31:24 INFO metabase.db :: Checking if Database has unrun migrations…
Jun 25 14:31:26 INFO metabase.db :: Database Migrations Current …
Jun 25 14:31:26 INFO metabase.db.migrations :: Running all necessary data migrations, this may take a minute.
Jun 25 14:31:27 INFO metabase.db.migrations :: Finished running data migrations.
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.notifications 
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.metabot-lifecycle
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.dependencies
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.activity-feed
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.last-login
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.revision
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.sync-database
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.view-log
Jun 25 14:31:27 INFO metabase.events :: Starting events listener: metabase.events.driver-notifications
Jun 25 14:31:27 INFO metabase.task :: Loading tasks namespace: metabase.task.send-anonymous-stats 
Jun 25 14:31:27 INFO metabase.task :: Loading tasks namespace: metabase.task.sync-databases
Jun 25 14:31:27 INFO metabase.task :: Loading tasks namespace: metabase.task.cleanup-temporary-computation-job-results
Jun 25 14:31:27 INFO metabase.task :: Loading tasks namespace: metabase.task.upgrade-checks
Jun 25 14:31:27 INFO metabase.task :: Loading tasks namespace: metabase.task.follow-up-emails
Jun 25 14:31:27 INFO metabase.task :: Loading tasks namespace: metabase.task.send-pulses
Jun 25 14:31:27 INFO metabase.core :: Metabase Initialization COMPLETE