Friday, February 24, 2012

Drive space for db and log backups

Hello all,
Can anyone tell me what is the ideal free space on a disk to allow for db
and log backups on a Full Recovery Model? My db is 4GB, and my log is 2.5GB.
How much free space should I keep to safely run regular backups?
Sincerely,
GeraldNone.
Backups should not be stored on the same machine, much less the same disks,
as your primary data store. Decide on your disaster recovery plan,
calculate how many backups you need to make it bulletproof, and then buy
disk space accordingly. Backup storage space doesn't have to be enterprise
grade stuff, but it should be reasonable reliable and fault tolerant.
Geoff N. Hiten
Senior Database Administrator
Microsoft SQL Server MVP
"Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in message
news:351EC7E4-1142-48C8-BEB0-4677D22FA78E@.microsoft.com...
> Hello all,
> Can anyone tell me what is the ideal free space on a disk to allow for db
> and log backups on a Full Recovery Model? My db is 4GB, and my log is
> 2.5GB.
> How much free space should I keep to safely run regular backups?
> --
> Sincerely,
> Gerald|||Geoff,
Thanks for your response. I do have backup files on a different partition.
What I'm asking is how much disk space should I have to ensure that the db
and log backup processes will take place safely?
Sincerely,
Gerald
"Geoff N. Hiten" wrote:

> None.
> Backups should not be stored on the same machine, much less the same disks
,
> as your primary data store. Decide on your disaster recovery plan,
> calculate how many backups you need to make it bulletproof, and then buy
> disk space accordingly. Backup storage space doesn't have to be enterpris
e
> grade stuff, but it should be reasonable reliable and fault tolerant.
> --
> Geoff N. Hiten
> Senior Database Administrator
> Microsoft SQL Server MVP
>
>
> "Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in messag
e
> news:351EC7E4-1142-48C8-BEB0-4677D22FA78E@.microsoft.com...
>|||I am unclear. If you are asking how much database and log space are
consumed during a backup operation, the answer is only enough log to hopd
the transaction history recorded during a full backup. Backups take space
equal to the allocated portion of the database in question plus the segment
of the log modified during the backup operation. Backups, in and of
themselves, do not force expansion of the log or the data files. As for how
much space, that depends on how many iterations of your backup you intend to
keep online at any given moment.
Geoff N. Hiten
Senior Database Administrator
Microsoft SQL Server MVP
"Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in message
news:59C902AF-BF2E-4F9F-BC69-2FB7EAAD6558@.microsoft.com...[vbcol=seagreen]
> Geoff,
> Thanks for your response. I do have backup files on a different partition.
> What I'm asking is how much disk space should I have to ensure that the db
> and log backup processes will take place safely?
> --
> Sincerely,
> Gerald
>
> "Geoff N. Hiten" wrote:
>|||Geoff,
Thanks for the response. What I'm asking is does the backup process use any
space on the same partition as the mdf or the ldf during the backup process
itself, which it would then clean up afterwards? In other words, can the
partition be full or close to full and allow SQL Server to successfully
backup the db and the log?
--
Sincerely,
Gerald
"Geoff N. Hiten" wrote:

> I am unclear. If you are asking how much database and log space are
> consumed during a backup operation, the answer is only enough log to hopd
> the transaction history recorded during a full backup. Backups take space
> equal to the allocated portion of the database in question plus the segmen
t
> of the log modified during the backup operation. Backups, in and of
> themselves, do not force expansion of the log or the data files. As for h
ow
> much space, that depends on how many iterations of your backup you intend
to
> keep online at any given moment.
> --
> Geoff N. Hiten
> Senior Database Administrator
> Microsoft SQL Server MVP
>
>
> "Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in messag
e
> news:59C902AF-BF2E-4F9F-BC69-2FB7EAAD6558@.microsoft.com...
>|||Ahh. It becomes clearer.
SQL does not use any file resources except the MDF, LDF, and .BAK files
specified to accomplish a backup.
One exception may be if you use the WITH STANDBY option to take the database
into standby mode. There must be room for the standby file, but you can
specify any valid local storage location for that file.
Geoff N. Hiten
Senior Database Administrator
Microsoft SQL Server MVP
"Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in message
news:F679B7FB-F8D3-48B2-9EB9-30460D9A8401@.microsoft.com...[vbcol=seagreen]
> Geoff,
> Thanks for the response. What I'm asking is does the backup process use
> any
> space on the same partition as the mdf or the ldf during the backup
> process
> itself, which it would then clean up afterwards? In other words, can the
> partition be full or close to full and allow SQL Server to successfully
> backup the db and the log?
> --
> Sincerely,
> Gerald
>
> "Geoff N. Hiten" wrote:
>|||A different partition on the same physical drive or array does nothing to
alleviate the issue Geoff mentioned. You need to backup to a different
physical drive or drive array to get the real benefits.
Andrew J. Kelly SQL MVP
"Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in message
news:59C902AF-BF2E-4F9F-BC69-2FB7EAAD6558@.microsoft.com...[vbcol=seagreen]
> Geoff,
> Thanks for your response. I do have backup files on a different partition.
> What I'm asking is how much disk space should I have to ensure that the db
> and log backup processes will take place safely?
> --
> Sincerely,
> Gerald
>
> "Geoff N. Hiten" wrote:
>|||Geoff,
Yes!! That's the question I wanted answered ... and my answer. Thanks for
hanging in there with me.
Sincerely,
Gerald
"Geoff N. Hiten" wrote:

> Ahh. It becomes clearer.
> SQL does not use any file resources except the MDF, LDF, and .BAK files
> specified to accomplish a backup.
> One exception may be if you use the WITH STANDBY option to take the databa
se
> into standby mode. There must be room for the standby file, but you can
> specify any valid local storage location for that file.
>
> --
> Geoff N. Hiten
> Senior Database Administrator
> Microsoft SQL Server MVP
>
>
> "Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in messag
e
> news:F679B7FB-F8D3-48B2-9EB9-30460D9A8401@.microsoft.com...
>|||Andrew,
Thanks for your response. Actually, the question was the one that Geoff
answered finally.
Sincerely,
Gerald
"Andrew J. Kelly" wrote:

> A different partition on the same physical drive or array does nothing to
> alleviate the issue Geoff mentioned. You need to backup to a different
> physical drive or drive array to get the real benefits.
> --
> Andrew J. Kelly SQL MVP
> "Gerald Hopkins" <GeraldHopkins@.discussions.microsoft.com> wrote in messag
e
> news:59C902AF-BF2E-4F9F-BC69-2FB7EAAD6558@.microsoft.com...
>
>

No comments:

Post a Comment