Xen back up jobs clarification

1

I have watched Toms video on this topic here

Im just a bit confused on Delta Backups specifically. I have a backup job called “Keep 2”. The backup retention is 2
Full backup interval is set to 10

Does this mean that i will do a full back up every 20 iteriations of the delta? So Full back up, Delta, Delta,Delta…Then Full back up on the 20th job? What happens if i don’t set a full backup interval number? It seems optional so does that mean a Full back up is never done? Is a Full backup implied when you first set the job and it first runs?

2

A full backup is done the first time a delta is run and unless you set a “Full backup interval” then all deltas will be built off that first full.