Using EELS

Calling eels_log_archive automatically

It is possible to call eels_log_archive(1Meels) automatically from within /etc/default/eels whenever the EELS database reaches a specific size. When eels_log_archive is called in this way, it behaves with the following characteristics:

all records successfully archived are purged from the database (-p option)
the archive name specified by the filename parameter (see below) is automatically appended with a date stamp
the command is always run in quiet mode

Take the following steps to customize EELS to archive the default database whenever it exceeds 30 megabytes in size:

Log in as root.
Add the following lines to the bottom of /etc/default/eels:
```
auto-archive archive_1 {
    source      default;
    query       "select * from events";
    filename    "/etc/eels/archives/eels_arch";
    trigger     30M;
    frequency   1H;
}
```
This parameter block specifies that EELS must check every hour that the size of the database specified in source does not exceed 30 megabytes in size. Once it does exceed 30 megabytes, use the SQL query specified in query to archive the contents of the database to filename and then purge that data from the database.
Save the changes to /etc/default/eels.
Restart EELS by entering the following commands:

/etc/init.d/eelsrc stop
/etc/init.d/eelsrc start

EELS immediately checks to see if the specified size (in this case 30 megabytes) has been reached. If it has, it automatically archives the records retrieved by query to the archive file and then removes those records from the database. The same check is then performed every hour.

The archive file can be restored at any time by using eels_log_restore(1Meels). For more information on restoring archives, see ``Restoring EELS database records''.