FoundationDB

Recovering a messed up installation - Start fresh / recreate default database


(Harry B) #1

Hello,

While experimenting with foundatiodb, I ended up having to blow away the installation ( I had to reformat the drive with certain settings changed ). Since I didn’t care for the tiny amount of test data I had, I stopped the instances and deleted the data and logs directory.

I took me several tries of dpkg -r and reinstall of all packages to finally get a working system back. What should I have done to “recreate the default db”. Is there any documentation regarding this?

Thanks


Harry


(A.J. Beamon) #2

If you delete all of your data files and then try to connect to the database, it should give you an error that looks like this:

The coordinator(s) have no record of this database. Either the coordinator
addresses are incorrect, the coordination state on those machines is missing, or
no database has been created.

  127.0.0.1:4500  (reachable)

At this point, you can reconfigure the database using the configure new command in fdbcli with your desired redundancy mode and storage engine:

> configure new single memory

In general, though, you should exercise caution when using configure new. It’s not much of an issue when you’re intentionally deleting a cluster, but running configure new in a cluster that hasn’t been configured will cause the processes in the cluster to delete all data files in their data directories. If a process is reusing an existing data directory, be sure to backup any files that you want to keep. Do not use configure new to fix a previously working cluster that reports itself missing unless you are certain any necessary data files are safe.

Note that running configure new in a cluster that is already configured doesn’t do any harm and instead prints an error:

ERROR: Database already exists! To change configuration, don't say `new'

This isn’t really documented currently, but there is a pull request to add some of this text to our documentation: