Recovery Manager

The Recovery Manager restores the QuantaStor internal configuration database from a backup. Use it when a system has been re-installed and you need the previous configuration back -- Storage Volumes, Network Shares, Users, Hosts, Schedules, Roles, and the other logical objects.

Navigation: Storage Management --> Storage Systems --> select a Storage System --> Recovery Manager (toolbar)

It is also on the right-click context menu for a Storage System.

Recovery Manager, listing the configuration database backups discovered on the started Storage Pools.

Your data does not depend on this database. Storage Pools, and the volumes and shares within them, carry their own metadata and are recovered by importing the pool -- not from this backup. The configuration database holds the logical objects layered on top. That is why a pool imported into a freshly installed system comes back with its volumes intact but without the hosts, schedules and users that referenced them.

In a Storage Grid the Recovery Manager matters much less, because the configuration database is replicated across all grid nodes. A node rejoining a grid picks the configuration up from its peers.

Using the Recovery Manager

1. Select the Storage System to recover.
2. Choose a backup from the list. Each row shows the backup name, its file size, and when it was created.
3. Optionally tick Include network configuration recovery -- see the warning below before you do.
4. Press OK.

The list is built from the backups discovered on the started Storage Pools. A pool that is not imported and started contributes nothing to the list, so if the backup you expect is missing, import the pool that holds it first.

How the backups are made

QuantaStor writes a copy of the configuration database to every Storage Pool on a rotation, so the backups travel with the storage rather than living only on the boot drive. Backups are named by their rotation slot:

• osn.db.backup.hourly.1 through osn.db.backup.hourly.N
• osn.db.backup.daily.1 through osn.db.backup.daily.N

N is controlled by max_db_backups in /opt/osnexus/quantastor/conf/quantastor.conf, which defaults to 5 of each. Values above 100 are capped at 100, and setting it to 0 disables the pool backups entirely. The local copy on the boot drive is written to:

/var/opt/osnexus/quantastor/osn.db.backup

...on a cadence set by hours_per_backup in the same file, which defaults to 12 hours.

A failure to write a backup raises a Configuration DB Backup Failure alert, so a system that has quietly stopped producing backups is visible in the Alert Manager rather than only discovered when a recovery is attempted. See Alert Manager.

Because the backup is an ordinary file, it can also be replicated off the appliance with rsync or sftp from a cron job if you want a copy outside the storage.

Important cautions

Recovering a database from a different system creates a duplicate identity. The database carries the system's unique ID. Restoring a backup taken from another server can leave two systems claiming the same UUID, which causes problems in a grid. Only restore a backup that came from the system you are restoring onto, unless OSNEXUS support has advised otherwise.

Network configuration recovery can cut off your own session. Ticking Include network configuration recovery restores the saved network settings, and if those differ from the current ones your connection drops when the address changes. Where all network ports may become unreachable, make the change from the console instead of the web interface, so you retain access.

For context, a newly installed QuantaStor system defaults to DHCP on an interface. If a DHCP server is present it takes an automatic address, giving you initial access from which to assign static addresses.

Restoring is not reversible in place. The restored database replaces the running configuration. If you are uncertain which backup is the right one, contact support before restoring rather than working through them by trial.

Restoring by hand

The database is a SQLite file and can be replaced directly if the dialog is not available -- for example on a system whose web interface will not start:

systemctl stop quantastor
cp <backup-file> /var/opt/osnexus/quantastor/osn.db
systemctl start quantastor

Getting help

Database recovery is one of the operations where it is worth asking first. If you are unsure which backup to use, or a recovery has not produced what you expected, contact OSNEXUS support at support@osnexus.com.

Related pages

• Storage System -- system-level configuration and the Modify dialog
• Upgrade Manager -- includes a full re-install / boot drive swap procedure that uses the Recovery Manager
• Alert Manager -- the Configuration DB Backup Failure alert