Database¶

Troubleshooting¶

Gisaf relies on counting features through Postgres statistics collector subsystem.

In case the server is restarted dirty (eg. without clean shutdown), then the count of the tables might be wrong or just 0, leaving the layers apparently empty and thus not even appearing.

The fix is as easy as:

sudo -u postgres psql avgis -c VACUUM

Installation¶

This documentation assumes that the Postgis package has been installed (see CSR_server).

Configure the server¶

Allow connections from other hosts in the local network¶

Set the server to listen to addresses, set listen_addresses to * in /etc/postgresql/9.6/main/postgresql.conf.

Allow the connections, add in /etc/postgresql/9.6/main/pg_hba.conf:

host all all 192.168.0.0/24 md5

Creation of the database¶

As postgres user:

createdb -E utf8 -T template0 avgis

Backups¶

Primary¶

The database is backed up every day at midnight. The dump file is located in /var/backups/postgres/.

Secondary¶

There are other backups (daily, weekly, monthly) thanks to Debian package autopostgresqlbackup), located (default) in /var/lib/autopostgresqlbackup.

Tertiary (dom0)¶

The whole virtual machine is backed up by BackupNinja on the "dom0" controller, using:
- rdiff backups every day
- tar files on Saturdays.

See /etc/backups.d on the dom0 (192.168.0.12).

Remote¶

TODO: remote backup.

Restoration¶

If the VM is not shutdown properly, there's a chance that the database is corrupt, and needs to be restored from one of the backups.

After the restoration, restart gisaf:

systemctl restart uwsgi.service

From primary backup¶

Note: the roles aren't restored with this method.

With user postgres:

# Optionally, rename the corrupt database (selecting a name for a database like "avgis_c2")...
psql -c "ALTER DATABASE avgis RENAME TO avgis_c2;" 
# ... or drop the existing database
psql -c "drop database avgis;" 
# Create a new database:
createdb -E utf8 -T template0 avgis
# Restore the database
pg_restore -d avgis /var/backups/postgres/avgis.pg_dump

From secondary backup¶

autopostgresqlbackup backs up the roles in postgres_globals.

zcat /var/lib/autopostgresqlbackup/daily/postgres_globals/postgres_globals_2018-10-24_06h25m.Wednesday.sql.gz | psql
zcat /var/lib/autopostgresqlbackup/daily/avgis/avgis_2018-10-24_06h25m.Wednesday.sql.gz | psql