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Spectrum Protect and The mystery of data reduction differences on the replication target

Posted by Stefan Folkerts 
Hi all,

I'm seeing something very strange at a customer site that has two Spectrum
Protect servers.
One receives backups and is the replication source.
The other is the replication target for that single source and doesn't
receive any backup data.
All data goes into a single containerpool on each server.

Check this out:

Containerpool on source:

Deduplication Savings: 35,173 G (52.50%)
Compression Savings: 16,083 G (50.54%)
Total Space Saved: 51,255 G (76.51%)

Containerpool on target:

Deduplication Savings: 3,962 G (6.19%)
Compression Savings: 34,193 G (56.97%)
Total Space Saved: 38,155 G (59.63%)

Deduplication is all but completely failing on the target.
Everything is replicated (replicate node *)
All filespaces and occupancy stats are equal on both sides.
Has anybody seen this before.
Running 8.1.7

Regards,
Stefan
This message was imported via the External PhorumMail Module
As the target server only receives already dedupped data it makes sense
their will be no or barely anything to be dedupped.

Regards,

Karel

On Mon, 8 Jul 2019 at 08:16, Stefan Folkerts <stefan.folkerts@gmail.com>
wrote:

> Hi all,
>
> I'm seeing something very strange at a customer site that has two Spectrum
> Protect servers.
> One receives backups and is the replication source.
> The other is the replication target for that single source and doesn't
> receive any backup data.
> All data goes into a single containerpool on each server.
>
> Check this out:
>
> Containerpool on source:
>
> Deduplication Savings: 35,173 G (52.50%)
> Compression Savings: 16,083 G (50.54%)
> Total Space Saved: 51,255 G (76.51%)
>
> Containerpool on target:
>
> Deduplication Savings: 3,962 G (6.19%)
> Compression Savings: 34,193 G (56.97%)
> Total Space Saved: 38,155 G (59.63%)
>
> Deduplication is all but completely failing on the target.
> Everything is replicated (replicate node *)
> All filespaces and occupancy stats are equal on both sides.
> Has anybody seen this before.
> Running 8.1.7
>
> Regards,
> Stefan
>
This message was imported via the External PhorumMail Module
I don't think that's how it works Karel, the values are based on managed
data and are normally around the same on the source and on the target.

On Mon, Jul 8, 2019 at 9:16 AM Karel Bos <tsm.wad@gmail.com> wrote:

> As the target server only receives already dedupped data it makes sense
> their will be no or barely anything to be dedupped.
>
> Regards,
>
> Karel
>
> On Mon, 8 Jul 2019 at 08:16, Stefan Folkerts <stefan.folkerts@gmail.com>
> wrote:
>
> > Hi all,
> >
> > I'm seeing something very strange at a customer site that has two
> Spectrum
> > Protect servers.
> > One receives backups and is the replication source.
> > The other is the replication target for that single source and doesn't
> > receive any backup data.
> > All data goes into a single containerpool on each server.
> >
> > Check this out:
> >
> > Containerpool on source:
> >
> > Deduplication Savings: 35,173 G (52.50%)
> > Compression Savings: 16,083 G (50.54%)
> > Total Space Saved: 51,255 G (76.51%)
> >
> > Containerpool on target:
> >
> > Deduplication Savings: 3,962 G (6.19%)
> > Compression Savings: 34,193 G (56.97%)
> > Total Space Saved: 38,155 G (59.63%)
> >
> > Deduplication is all but completely failing on the target.
> > Everything is replicated (replicate node *)
> > All filespaces and occupancy stats are equal on both sides.
> > Has anybody seen this before.
> > Running 8.1.7
> >
> > Regards,
> > Stefan
> >
>
This message was imported via the External PhorumMail Module
Stefan,
I understand it as Karel.
The replicate (or protect stg) process data is deduplicated at the source.
It would be inefficient to consume network bandwidth sending duplicate extents.

-Rick Adamson


-----Original Message-----
From: ADSM: Dist Stor Manager <ADSM-L@VM.MARIST.EDU> On Behalf Of Stefan Folkerts
Sent: Monday, July 8, 2019 3:23 AM
To: ADSM-L@VM.MARIST.EDU
Subject: Re: [ADSM-L] Spectrum Protect and The mystery of data reduction differences on the replication target

* This email originated outside of the organization. Use caution when opening attachments or clicking links. *

----------------------------------------------------------------------
I don't think that's how it works Karel, the values are based on managed data and are normally around the same on the source and on the target.

On Mon, Jul 8, 2019 at 9:16 AM Karel Bos <tsm.wad@gmail.com> wrote:

> As the target server only receives already dedupped data it makes
> sense their will be no or barely anything to be dedupped.
>
> Regards,
>
> Karel
>
> On Mon, 8 Jul 2019 at 08:16, Stefan Folkerts
> <stefan.folkerts@gmail.com>
> wrote:
>
> > Hi all,
> >
> > I'm seeing something very strange at a customer site that has two
> Spectrum
> > Protect servers.
> > One receives backups and is the replication source.
> > The other is the replication target for that single source and
> > doesn't receive any backup data.
> > All data goes into a single containerpool on each server.
> >
> > Check this out:
> >
> > Containerpool on source:
> >
> > Deduplication Savings: 35,173 G (52.50%)
> > Compression Savings: 16,083 G (50.54%)
> > Total Space Saved: 51,255 G (76.51%)
> >
> > Containerpool on target:
> >
> > Deduplication Savings: 3,962 G (6.19%)
> > Compression Savings: 34,193 G (56.97%)
> > Total Space Saved: 38,155 G (59.63%)
> >
> > Deduplication is all but completely failing on the target.
> > Everything is replicated (replicate node *) All filespaces and
> > occupancy stats are equal on both sides.
> > Has anybody seen this before.
> > Running 8.1.7
> >
> > Regards,
> > Stefan
> >
>

**CONFIDENTIALITY NOTICE** This electronic message contains information from Southeastern Grocers, Inc and is intended only for the use of the addressee. This message may contain information that is privileged, confidential and/or exempt from disclosure under applicable Law. This message may not be read, used, distributed, forwarded, reproduced or stored by any other than the intended recipient. If you are not the intended recipient, please delete and notify the sender.
This message was imported via the External PhorumMail Module
Well, I don't think that's correct Rick. :-)
The data is deduplicated and compressed at the source and only the new
chunks are replicated to the target daily but the data reduction
information on the target storagepool is based on the managed data figures
just like at the source and they are the same.
That's why we see percentages, they are the percentages based on the
managed data within that containerpool.
If it works like you said I would see no deduplication or compression on
the target because it's only replicated data on that machine.
There is no data on the target machine that's not on the source machine.

On Tue, Jul 9, 2019 at 5:27 PM Rick Adamson <RickAdamson@segrocers.com>
wrote:

> Stefan,
> I understand it as Karel.
> The replicate (or protect stg) process data is deduplicated at the source.
> It would be inefficient to consume network bandwidth sending duplicate
> extents.
>
> -Rick Adamson
>
>
> -----Original Message-----
> From: ADSM: Dist Stor Manager <ADSM-L@VM.MARIST.EDU> On Behalf Of Stefan
> Folkerts
> Sent: Monday, July 8, 2019 3:23 AM
> To: ADSM-L@VM.MARIST.EDU
> Subject: Re: [ADSM-L] Spectrum Protect and The mystery of data reduction
> differences on the replication target
>
> * This email originated outside of the organization. Use caution when
> opening attachments or clicking links. *
>
> ----------------------------------------------------------------------
> I don't think that's how it works Karel, the values are based on managed
> data and are normally around the same on the source and on the target.
>
> On Mon, Jul 8, 2019 at 9:16 AM Karel Bos <tsm.wad@gmail.com> wrote:
>
> > As the target server only receives already dedupped data it makes
> > sense their will be no or barely anything to be dedupped.
> >
> > Regards,
> >
> > Karel
> >
> > On Mon, 8 Jul 2019 at 08:16, Stefan Folkerts
> > <stefan.folkerts@gmail.com>
> > wrote:
> >
> > > Hi all,
> > >
> > > I'm seeing something very strange at a customer site that has two
> > Spectrum
> > > Protect servers.
> > > One receives backups and is the replication source.
> > > The other is the replication target for that single source and
> > > doesn't receive any backup data.
> > > All data goes into a single containerpool on each server.
> > >
> > > Check this out:
> > >
> > > Containerpool on source:
> > >
> > > Deduplication Savings: 35,173 G (52.50%)
> > > Compression Savings: 16,083 G (50.54%)
> > > Total Space Saved: 51,255 G (76.51%)
> > >
> > > Containerpool on target:
> > >
> > > Deduplication Savings: 3,962 G (6.19%)
> > > Compression Savings: 34,193 G (56.97%)
> > > Total Space Saved: 38,155 G (59.63%)
> > >
> > > Deduplication is all but completely failing on the target.
> > > Everything is replicated (replicate node *) All filespaces and
> > > occupancy stats are equal on both sides.
> > > Has anybody seen this before.
> > > Running 8.1.7
> > >
> > > Regards,
> > > Stefan
> > >
> >
>
> **CONFIDENTIALITY NOTICE** This electronic message contains information
> from Southeastern Grocers, Inc and is intended only for the use of the
> addressee. This message may contain information that is privileged,
> confidential and/or exempt from disclosure under applicable Law. This
> message may not be read, used, distributed, forwarded, reproduced or stored
> by any other than the intended recipient. If you are not the intended
> recipient, please delete and notify the sender.
>
This message was imported via the External PhorumMail Module
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