Snap Manager for SQL Workshop

Backup and RecoverySnap Manager for SQL Server

Introduction Workshop

Brendon Higgins

Leeds, WestOne

November 2008

Date of presentation - Nov 2008SnapManager For SQL Workshop.ppt 2

Agenda

Introduction

Description of system components

Summery of components

SMSQL Interface overview

SMSQL Management

Verification Process

SnapInfo {Transaction Logs & Reports}

Questions and Answers

Other Available Documents


Introduction

Backup, what's the point?

"7 of 10 small firms that experience a major data loss go out of business within a year" DTI/PriceWaterhouse Coopers, 2004

"Hard disk drives have two states: crashed and about to crash" anon

"And then what happened…" unhappy boss


SAN vs DAS

RAID Volume

LUN

SCSI

FCP / iSCSI

Direct Attach Storage

Storage Area NetWork


Storage Area Network

For Very scalable - PetaBite, ExaByte, ZettaByte and YotaByte

High performance {Operations per second / throughput}

Snapshot Technology

Enables Clustering and VMotion Technologies

Against Cost

Complexity


Snapshot

A snapshot is a 'frozen' point in time copy of all the data

The snapshot process is extremely fast and does not require host to stop accessing the data

Once completed the snapshot is available on a read only basis

Snapshots only contain the changed data between snaps


SnapMirror

SnapMirror is the name of the process used to copy the data contained within the volume or qtree to a 2nd location

SnapMirror can be used to within the filer or to a remote filer

SnapMirror can be cascaded to multiple filers

SnapMirror is based on snapshot technology

Once the SnapMirror has been created, updates are sent with only the blocks of data which have changed

SnapMirror can be used in three different modes: asynchronous, synchronous, and semi-synchronous


FlexClone

NetApp FlexClone technology allows the read only snapshot to be mounted as a writable disk. Enabling multiple copies of the database to be available.

i.e. For development / testing or single file recovery


SnapRestore

Does what is says on the tin

The whole volume / qtree is restored

Process is one way

Snapshot rollback process is very fast

Process Overview

Take the host off line {just drives only if required}

Select common snapshot across volumes

Instruct filer to revert to snapshot

Bring host back on line


SnapDrive

Removes complexity from tasks

Enabler of error-free, host-consistent data Snapshots

SnapDrive for Windows is a purchased product

Installed onto the host

Wizard-based interface to create and manage storage

Microsoft Cluster Server aware

sdcli.exe CLI enables SnapDrive commands entered individually or through automation scripts


Microsoft's Volume Shadow Copy Service

VSS is built into XP and 2003 Server

Mechanism for creating consistent point-in-time copies

Standard set of extensible APIs

Prevent torn writes by enabling applications to flush partially committed data from memory

VSS can produce consistent shadow copies by coordinating with business applications, file-system services, backup applications, fast recovery solutions, and storage hardware


Volume Shadow Copy Service Architecture Diagram

SnapDrive

NetApp

FAS 3050

activity status power

Requestor(SnapManager

for SQL)VSS

VSS Hardware Provider

SnapDrive Service

Writer(Microsoft SQL Server 2003)

Host


Snapshot Retention Period

Although snapshots can be small in size they can consume significant space over time. They should be archived to tape and then deleted to return disk capacity to the storage system.

Options Mount the LUN/s in the read only snapshot as a 'windows disk' and write the

individual files to tape using a 3rd party backup application Use NDMP to write the volume with it's LUN/s to tape


SMSQL Backup

SMSQL application is only used to backup up the SQL server DATA. The operating system, installed applications and files on none SQL disks within the system are NOT protected via the SnapManager for SQL Server application.


Summery of components

The operating system does not recognise any difference between a LUN or an internal disk. They are both disks.

A snapshot is a point in time copy of the data

SnapMirror copies volumes / qtrees and their snapshots

Snapshots can either be mounted or made active in a process know as SnapRestore

Microsoft's Volume Shadow Copy Service is part of the Windows operating system

Microsoft's Volume Shadow Copy Service is the mechanism used for creating consistent point-in-time copies

SMSQL does not archive to tape directly or protect none SQL Data

SnapManager For SQL Server Interface and Operation


SnapManager for SQL Server

NetApp - SMSQL Screen shot


SMSQL - Backup and Verification



Backup and Verification Jobs



sdcli.exe

C:\Program Files\NetApp\SnapManager for SQL Server\SmSqlBi.exe -H “AnameV01" -D 6 -R -G -S “AnameV01" -C 0 -N -Daily -UN -UM



SMSQL - Available Backups



SMSQL - Delete Old Snapshots

Backup policy states a set number of backups will be kept. Do not delete old backups unless the system has failed to remove them automatically or follow change procedure.



SMSQL - Restore and Verification Status



SQL Server Backup / Restore Options

There are many ways of recovering from a problem on an SQL Server using SMSQL. The key factor is:

Rewind the disks to last snapshot

or

Start pulling back just specific parts of the data

See SnapManager 2.1 for Microsoft SQL Server, Installation and Administration guide for details.


Verification Architecture Diagram

MSCS

FlexClone

Verification Server

DBCC

CHECKDC


Verification Problem

The internal HDD should not be listed in the Snapdrive MMC under disks. Reboot the verification server.

NetApp - Snapdrive Screen shot


Transaction Logs

SnapManager actively manages the SQL Server transaction logs. It is therefore very important that end users do not delete transaction logs. Many backup applications also manage SQL Server transaction logs so it is important that only SnapManager for SQL Server is used to backup the SQL Server environment.


SNAPINFO


Configuration Problem - SNAPINFO full



SMSQL Reports



Shadow Copy Creation Process

Microsoft - VSS Diagram


SQL Server Backup Process

1. SnapManager determines which LUNs it wants to capture and makes sure that SQL Server 2003 is present as a valid writer

Getting SQL Server Database Information, please wait...

2. SnapManager initiates the shadow copy process*** STARTING SQL SERVER ONLINE BACKUP PROCESS

3. VSS informs SQL Server and the NetApp VSS Hardware Provider that a shadow copy is starting. SQL stops writing to disk

SQL Server is prepared to freeze the database now

Ready to prepare to create snapshot...

4. VSS ensures that NTFS is in a consistent stateSQLServer is aware that the snapshot is successful.



5. VSS requests the NetApp VSS Hardware Provider to create a shadow copy

Snapshot virtual disk E, G: for database

Transaction log backup for database

6. The NetApp VSS Hardware Provider requests SnapDrive to create a Snapshot copy of the storage system volume that contains the specified LUN.

Creating Snapshot of Virtual Disk Drive

7. SnapDrive requests the storage system to create a Snapshot copy of the specified volume

Snapshot virtual disk E, G: for database



8. When the shadow copy is complete, VSS returns NTFS to a normal state and informs SQL that it can resume disk writes

[Microsoft][ODBC SQL Server Driver][SQL Server]BACKUP DATABASE successfully processed

9. VSS manages the shadow copy of the LUN based on the attributes specified by the requestor. For example, VSS could mount the LUN in a Snapshot copy. In a case, however, in which SnapManager is the requestor, SnapManager tells VSS to forget about the shadow copy it just created. This enables SnapManager to have complete control of the Snapshot copy

**** FULL DATABASE BACKUP RESULT SUMMARY #1 ****


Questions and Answers


Further Reading

SnapManager 2.1 for Microsoft SQL Server, Installation and Administration guide

Data ONTAP® 7.2, Data Protection, Tape Backup and Recovery Guide

http://technet.microsoft.com/en-us/library/cc738819.aspx

Storage Area Network Foundation Workshop

NetApp SnapMirror® Best Practices Guide

http://now.netapp.com

IS S 0092 Maintenance Procedure - Instructions - Recover SQL Database From Snapshot.doc {Worksite Code: 4288334}

Snap Manager for SQL Workshop

Documents

Transcript of Snap Manager for SQL Workshop