Day of month GFS for Backup Copy with synthetic full+ReFS

[torteflo]

Hi,

I look for other related topics, but I did not found my answers at the moment
I haven't opened a support case, as this is more a configuration question

Some basic infos first :
- Veeam B&R 9.5u4, vSphere 6.5, 2 sites
- Veeam server on a VM (win2016)
- 1 physical server with proxy + repository roles, in each site (win2016)
- ReFS and synthetic full used on backup and backup copy
- among other few VMs, there is 2 big VMs, 1 each site, each with around 15 TB of datas
- Backup Jobs keeps 31 restore points
- Backup Copy Jobs keep 7 restore points ad GFS 12 monthly, but we got to change it, and this is the big question here

We had a big issue with past ReFS partition, with RAID6 issues and corruption, it seems all due to a bad firmware on the SmartArray RAID card when array was created.
So it was a real mess, and now we started everything fresh since a week

What is needed here is to have precisely GFS monthly backups, without any holes in it, even 1 day or some hours
It is mandatory for legal reasons

So we recreated Backup Copy Jobs with GFS 12 monthly (in the past it was 52 weekly), start interval is at 6am.
But obviously we cannot keep default setting for monthly "first sunday of month", because sometimes it will be the 3rd of the month, next month the 5th e.g, and we will have a hole in backup between the 3rd and the 5th
I hope at least a part of it is clear here...? Well, hope is the start of hapiness, but does not resolve anything

Now I see I can modify my monthly GFS to 1st day of month
It could work for us, but what are the cons to do that ?
AFAIK Backup Copy Job copies an increment from source each day and create a synthetic full the day we specify in its restore points, here saturday
And it keeps the full for archival purpose if we ask in GFS, but until now it was only once a week

So when 1st day of month wont be a saturday, what will happen ? It will create 2 synthetic full in the week ?

Also if we change this setting now I read it will keep 2 full backup with same flag, during 1 year, is it ?
It will still be synthetic fulls with ReFS optimization I suppose (fast clone and space savings)


Please help, any advice would be most welcome

[foggy]

AFAIK Backup Copy Job copies an increment from source each day and create a synthetic full the day we specify in its restore points, here saturday

Not a synthetic full as in a backup job, but it rather puts aside the current full backup marking it as a GFS restore point and creates new full based on it and the latest increment to serve as the base of the regular chain.

So when 1st day of month wont be a saturday, what will happen ? It will create 2 synthetic full in the week ?

Why should it be Saturday? If you specify the 1st day of the month, the corresponding full restore point containing the VM state as of this day will be put aside as a GFS one.

Also if we change this setting now I read it will keep 2 full backup with same flag, during 1 year, is it ?

Could you please clarify this question?

It will still be synthetic fulls with ReFS optimization I suppose (fast clone and space savings)

Correct.

[torteflo]

Hi,

Thank you for your fast answer

Why should it be Saturday? If you specify the 1st day of the month, the corresponding full restore point containing the VM state as of this day will be put aside as a GFS one.

I suppose that's the thing I don't fully understand here
In my 7 first restore points of backup copy jobs, I have 1 weekly Full and 6 dayly increments (or even up to 2 full and 12 increments if it's as Backup job forward incremental retention policy)
And these weekly fulls are made each saturday
This is the regular chain of the backup copy, as you said, if I understand correctly

So when the monthly will fall another day of the week, what will Veeam do plz ? it will create a new full with last restore point ? or only flag the last full already created as monthly GFS ?
As I said I can't have a gap / deviation, I don't know a better in english sorry, in monthly backup we keep : we must keep a monthly full each 1st day of month, or each 31 (well bad idea for february indeed)
I suppose it cannot be fully guaranteed, if there is a failure or anything, but at least when everything's fine, should it work the way we wish ?

Could you please clarify this question?

I read it here :
https://helpcenter.veeam.com/archive/ba ... cycle.html

[torteflo]

Another way to ask my question could be :

If you specify the 1st day of the month, the corresponding full restore point containing the VM state as of this day will be put aside as a GFS one.

Precisely, the restore point containing VM state of this day won't be a full. Will it build a new full at this date with its lastest increments ?

[torteflo]

Well, even knowing I really ask too much here, I try already to make a "Up"
Maybe Alexander your first answer was so quick that I thought we were having a chat session
My hurry is because we are soon the 1st of month, so I should/must change our options before monday, but I would like to know the real effects before
Thank you !

[foggy]

In my 7 first restore points of backup copy jobs, I have 1 weekly Full and 6 dayly increments (or even up to 2 full and 12 increments if it's as Backup job forward incremental retention policy)
And these weekly fulls are made each saturday

Seems you have the 'Read from source..." check box enabled which effectively switches the backup copy job from forever forward to a simple forward incremental mode with periodic fulls.

So when the monthly will fall another day of the week, what will Veeam do plz ? it will create a new full with last restore point ?

Yes, as described here, it will create the new full on the designated day and start the backup chain anew - incremental backups will be created until the next GFS full is created. So basically there will be two fulls during a single week in this case.

I suppose it cannot be fully guaranteed, if there is a failure or anything, but at least when everything's fine, should it work the way we wish ?

Yes.

[torteflo]

Seems you have the 'Read from source..." check box enabled which effectively switches the backup copy job from forever forward to a simple forward incremental mode with periodic fulls

no, this box is unchecked
For ReFS to be use by backup copy

Yes, as described here, it will create the new full on the designated day and start the backup chain anew - incremental backups will be created until the next GFS full is created. So basically there will be two fulls during a single week in this case.

Okay, that's what I was really not sure about

Thank you !

[foggy]

Then I don't understand this:

In my 7 first restore points of backup copy jobs, I have 1 weekly Full and 6 dayly increments (or even up to 2 full and 12 increments if it's as Backup job forward incremental retention policy)
And these weekly fulls are made each saturday

As in this case, GFS should work like this.

[torteflo]

Yes you are right
I have only 1 full in the dayly chain

[foggy]

Well, anyway, in this case, you will also have separate GFS points for weekly and monthly, the only difference would be that each of them will be put aside not on the specified day but on the day when the full backup in the regular chain reaches that specified day.

[torteflo]

Hi,
well, thank you Alexander, but can I ask you a little more patience maybe
Because you 've kind of lost me on a new point here!
Sorry for being a burden!

So :

in this case, you will also have separate GFS points for weekly and monthly

I understood this one yes

the only difference would be that each of them will be put aside not on the specified day but on the day when the full backup in the regular chain reaches that specified day

What do you mean, can you make an example please ?

These days for example
It has built a full on saturday 30th may for regular chain and weekly GFS
Then 1st june is a monday, it builds a new full for monthly GFS
Then it builds a new full on saturday 6th june for regular chain and weekly GFS, and he put aside 30th may for weekly GFS
Then, when will the monthly GFS be put aside ? 8th june or not ?

[foggy]

It will not build the monthly full exactly on June, 1st since on that day the full backup in the regular chain (the one that serves as the base for the GFS full) contains the VM state of an earlier date. The new full will be built and the GFS restore point will be put aside when the regular chain full will reach the VM state as of June, 1st. The regular full 'moves' forward each day with a merge of the oldest increment into it - please review the retention process description once again for better understanding.

[torteflo]

Okay, now understood ! aleluia !
Then it will create a full for 1st june the 8th june I suppose and put it aside the same day, 8th june, for GFS
You were right to ask me to read same link twice, because first time was not enough..

Last question if you re not bored already..
Now with this kind of forever incremental scheme, isn't the full going to grow always bigger and bigger ?
Do we have to enable Defragment and compact full backup option if we don't want to ?

Thank you for your time and efforts

[veremin]

Now with this kind of forever incremental scheme, isn't the full going to grow always bigger and bigger ?

Correct.

Do we have to enable Defragment and compact full backup option if we don't want to ?

Correct.

Thanks!

[foggy]

Actually the latter is not necessary since you have GFS enabled - when the GFS restore point is put aside, the new regular full is created from those blocks that are actually required, which is basically the same that compact does.

[torteflo]

Okay, thank you all, mostly Alexander thanks a lot !