The built-in database is fault-tolerant and does not require administration. However, it has occurred in some rare cases that database has been corrupted. In this case, the following options are possible:

1. database deletion and subsequent loading of data from scratch

   Stop dpi
   service fastdpi stop
   Delete database
   /bin/rm /var/db/dpi/*
   Launch dpi
   service fastdpi start
   Load all settings in the database from scratch 

2. database recovery with data transfer

   Stop dpi
   service fastdpi stop
   Run script
   mdb_dump -a -f dump.txt /var/db/dpi
   /bin/rm /var/db/dpi/*
   mdb_load -f dump.txt /var/db/dpi
   Launch dpi
   service fastdpi start

User data repository or UDR is a built-in database. It permanently stores data on services and policing configuration for operator's subscribers. UDR activation is required to support dynamic IPs and subscribers with several IPs.

UDR is activated by configuration parameter in file /etc/dpi/fastdpi.conf:

udr=1

The database is placed to /var/db/dpi.