Re: [BackupPC-users] Number of incrementals before a full backup

[Craig B. <cba...@us...>]

Nicolai Nordahl Rasmussen writes:

> Is it "hardcoded" into backuppc that a minimum of 6 incrementals is
> needed, before a full backup is made?

No.

> I've used the $Conf{BlackoutPeriods} parameter to specify sundays as "b=
ackup-free" zone.=20
> I dont want to do any backups on sundays, as I use 12-15 hours of the s=
unday, to archive the latest backups (with the arch2usb script) to an ext=
ernal harddrive. I have 5 hosts, total pool size is around 130gb atm.
>=20
> My problem then is:
>=20
> I normally have full backups running on SATURDAYS. Because the whole su=
nday->monday night (around 19.30pm) is blacked out,
> an incremental backup is "skipped". The next week, instead of doing the=
 full backup on saturday (with 5 incrementals between) it does an increme=
ntal, even though the FullPeriod has expired.
>=20
> Here is a snip of the config file:
>=20
> $Conf{BlackoutPeriods} =3D [
>     {
>         hourBegin =3D>  7.30,
>         hourEnd   =3D> 19.30,
>         weekDays  =3D> [1, 2, 3, 4, 5],
>     },
>     {
>         hourBegin =3D>  0.02,
>         hourEnd   =3D> 23.98,
>         weekDays  =3D> [0],
>     },
>     {
>         hourBegin =3D>  0.02,
>         hourEnd   =3D>  19.30,
>         weekDays  =3D> [1],
>     },
> ];
>=20
> $Conf{FullPeriod} =3D 6.97;
> $Conf{IncrPeriod} =3D 0.97;
>=20
> This means - since backuppc seems to want 6 incrementals before a full
> can be made - that the day of the FULL backup cycles around all the
> time. A full backup of one of my hosts takes up to 15 hours, and thus
> runs during working hours - I dont want this to happen, which is why I
> wanted the full backups to be done on saturdays.

Both $Conf{IncrPeriod} has to have elapsed since the last incremental,
and $Conf{FullPeriod} has to have elapsed since the last full for
a full backup to occur.

You should look carefully at the backup times.  Let's assume the Saturday=

full starts sometime during the day.  Your Sunday blackout means the
incrementals happen early in the morning on Mon-Fri.  Early Saturday
morning, $Conf{FullPeriod} hasn't elapsed yet so another incremental
is done.  Therefore a full won't start on Saturday - it will start
Monday early morning after the blackout.

You can solve this two ways: decrease $Conf{FullPeriod} to, eg, 6.2 days
and manually start a full backup late Friday night to get back on to
schedule, or you can use BackupPC_serverMesg with cron to force the
full to happen on a particular time on Saturday.

Craig