backup/ getting started: backup school
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BACKUP/ GETTING STARTED: Backup School. Presented by: W. Curtis Preston VP, Services Development GlassHouse Technologies. Making good on your investment. Many SANs are built in order to simplify backup yet often fail for lack of good design, processes and procedures - PowerPoint PPT PresentationTRANSCRIPT
BACKUP/GETTING STARTED:
Backup School
Presented by:W. Curtis Preston
VP, Services DevelopmentGlassHouse Technologies
Making good on your investment
Many SANs are built in order to simplify
backup yet often fail for lack of good design,
processes and procedures
There are several common mistakes that
people make when building a backup system
Avoiding these mistakes and taking proper
action can create a backup system that is
reliable and restorable
What will we cover?
Common backup configuration mistakes
How to avoid them
• Sizing your backup system
• Configuration examples for NetBackup
• Configuration examples for NetWorker
Common backup configuration mistakes
Where do these lessons come from?
Audits of real backup and recovery systems
Lessons learned from real horror stories
Many, many sleepless nights
Too little power
Not enough tape drives
Tape drives that aren’t
fast enough
Not enough slots in the
tape library
Not enough bandwidth
to the server
Too much powerStreaming tape drives must be
streamed
If you don’t, you will wear out
your tape drives and decrease
aggregate performance
Must match the speed of the
pipe to the speed of the tape
You can actually increase your
throughput by using fewer tape
drives
Not using multiplexing Defined: Sending multiple
backup jobs to the same drive simultaneously
Again, drives must be streamed
Multiplexing will impact restore performance but not as much as you might think
Multiplexing can actually help your restore just as it can help your backups
Using multiplexing can greatly increase the utilization of your backup hardware
Tape drive
Backup Job
Backup Job
Backup Job
Backup Job
Not using multistreaming
Defined: Sending
multiple simultaneous
backup jobs from a
single client
Large systems cannot
be backed up serially
Multistreaming creates
a different job for each
file system
Backup Job
Backup Job
Backup Job
Backup Job
Server
Using include listsMost major backup
software supports file
system discovery
Still, many administrators
use manually created
include lists
Any perceived value is
significantly outweighed
by the risk it creates
Too many full backupsIf you are using a commercial backup and
recovery product with automated media
management and multiple levels, weekly full
backups are a waste of tape, time and money
Monthly full backups, weekly cumulative
incrementals (1), and daily incrementals (9)
work just as well and use ¼ as much tape
Depending on the level of incremental activity,
quarterly backups can work just as well
Not standardizing
Creating custom configurations for each
client is easier, but much riskier
Creating a standard backup client
configuration can significantly decrease risk
Create a standard exclude list, etc. and push
it out to each client
Not even noticing!
Backups go ignored so
often. It’s like they’re the
bill collector nobody wants
to talk to.
Backup reporting products
can really help automate
easy reporting
Don’t ignore backups.
They will bite you.
It’s just backups, right?
“I’m an experienced, seasoned systems
administrator. This is just backups. How
hard can they be?”
The data being backed up has become very
complex, and the complexity of backup
systems has matched that complexity with
equally complex functionality.
Not thinking about diskTape is not as cheap as you
thought
Let’s examine a 4 TB library:
20 slots, 2 drives $17K
20 tapes, $70 apiece $14K
Robotic license $10K
Total $41K
(does not include labor costs)
That’s about $10/GB
LIBRARY STORAGE MODULE
9710
StorageTek
EXIT
ENTER MENU
*
Disk is cheaper than you thought
ATA-based storage arrays as low as $5/GB(disk only, needs file system)
Special function arrays• Quantum DX-30 looks and behaves like a Quantum P1000.
Can be used as target for “tape-based” backups (3 usable TB, $55K list, or $18/GB)
• NetApp R100 looks like other NetApp filer. Target for SnapVault and disk-based backups, source for SnapMirror (9+ usable TB, $175K list, or $18/GB)
ATA disks not suited for heavy, random access, but perfect for large block I/O (e.g., backups!)
You can do neat things with diskIncremental backups are one of
the greatest backup performance challenges
Use as a target for all incremental backups. (Full, too, if you can afford it.)
For offsite storage, duplicate all disk-based backups to tape
Leave disk-based backups on disk
Now that I know…
Building a reliable and restorable backup system
Sizing the backup system
Server size/Power I/O performance more important than CPU
power
CPU, memory, I/O expandability paramount
Avoid overbuying by testing prospective
server under load
If you use Suns, you’ve got snoop and truss
Catalog/Database size Determine number of files (n)
Determine number of days in cycle (d)
(A cycle is a full backup and its associated incremental
backups.)
Determine daily incremental size (i = n * .02)
Determine number of cycles online (c)
150-250 bytes per file, per backup
Use a 1.5 multiplier for growth and error
Index Size = (n + (i*d)) * c * 250 * 1.5
Library size: Drives
Network backup
• Buy twice as many backup drives as your
network will support
• Use only as many drives as the network will
support. (You will get more with less.)
• Use the other half of the drives for duplicating
Library size: Drives (2) Local backup
• Most large servers have enough I/O bandwidth to back themselves up within a reasonable time if you’re using NetBackup
• Usually a simple matter of mathematics: 8 hr window, 8 TBs = 1 TB/hr = 277 MB/s 30 10 Mb/s drives, 15 20 MB/s drives
• Must have sufficient bandwidth to tape drives
• Filesystem vs. raw recoveries
Allow drives and time for duplicating
Library size: Slots (all-tape environment)
Should hold all onsite tapes
Onsite tapes automatically expire and get
reused
Only offsite tapes require physical mgmt.
Should monitor library via a script to
ensure that each pool has enough free
tapes before you go home
Watch for those downed drive messages
Library size: Slots (disk/tape environment) Do incremental backups to disk
Library needs only to hold onsite full tapes and the latest set of copies
On-site tapes and disk-based backups automatically expire and get reused
Only offsite tapes require physical mgmt.
Should monitor library and disk via a script to ensure that each pool has enough free tapes before you go home
Watch for those downed drive messages
Local or remote backup?Throughput (in 8hrs), if you “own the wire:”
• 10 Mb = 20 GB, 100 Mb = 200 GB
• GbE = 500 GB – 1 TB (Also must “own the box.”)
Greater than 500 GB should be “local”• LAN-free backups allow you to share a large tape library by
performing “local” backups to a “remote, shared” device
• More than one 500+ GBserver, buy a SAN!
• Only one 500+ GB server, plan for a SAN!
(NetBackup= SSO, NetWorker=DDS)
BACKUP/GETTING STARTED:Backup School, Part 2
W. Curtis Preston
VP, Services Development
GlassHouse Technologies
Multistreaming: NetBackupDefined: Starting multiple simultaneous backup jobs from a
single client
• Maximum jobs per client > 1
• Check “Allow multiple data streams.”
• ALL_LOCAL_DRIVES, or multiple entries in file list
• Maximum jobs per policy > 1 or unchecked
• Need storage unit with more than one drive, or one drive
with multiplexing enabled
• Can change max jobs per client using the Server
Properties -> Clients tab (4.5)
• By default, will not exceed one job per filesystem, but can
bypass this if you make your own file list
Multistreaming (Parallelism): NetWorker
Use “All” saveset or multiple entries in the saveset list
Set the parallelism setting for server and, if necessary, the storage node
Set client parallelism value in client attributes
Must have multiple drives available, or one drive with target sessions set higher than one
Will not exceed number of disks or logical volumes on the client (see maximum-sessions in manual)
Multiplexing: NetWorkerSet target sessions
per device,
allocating how many
sessions may be
sent to that device
Global setting for all
backups that go to
that device
Multiplexing: NetBackup
Max multiplexing per drive in storage unit
configuration > 1
Media multiplexing in schedule > 1• Use higher multiplexing for incremental backups if
going to tape (6-8)
• Use lower multiplexing for local backups (2)
• No need to multiplex disk storage units
Multiple policies can multiplex to the same
drive, but multiple media servers cannot
Using Include lists -- notNetBackup – ALL_LOCAL_DRIVES in file list
NetWorker – All in saveset field
Automatically excludes NFS/CIFS drives
Does not include dynamically mounted drives not in /etc/*fstab
What about database clients?
Use scripts that parse lists of databases:• /var/opt/oracle/oratab for Oracle
• MS-SQL list in registry
• Master database in Sybase
Some backup products support “All” for
databases
Remember to write standardize script
with parameters to backup databases
Incremental backups: NetBackupCreate staggered monthly full backups using
calendar-based scheduling
Create staggered weekly cumulative incrementals using CBS
Create daily incremental backups using frequency-based backups
(Check Allow after run day)
Delete window from previous day for CBS
Incremental backups: NetWorker
Do not use the Default schedule!
Create 28 schedules with a monthly full,
weekly level 1, and daily incremental; name
them after the full day
Do not specify a schedule for the Group
Assign the 28 schedules evenly across all
clients based on size
Standardization: NetWorker
Use All saveset
entry
To exclude files,
use standard
directives for all
clients
Standardization: NetBackupUse ALL_LOCAL_DRIVES
Non-Windows clients:
Use standard exclude list and
push out from master using
bpgp.
Windows clients:
Use standard exclude list and
push out from master using
bpgetconfig –M and
bpsetconfig –h.
Backup reporting: NetBackupWatch activity and device
monitors
bperror
bpdbjobs -report
bpdbjobs –report –all_columns
/usr/openv/netbackup/logs
/usr/openv/logs
/usr/openv/volmgr/logs
Backup reporting: NetWorker
Watch nwadmin screens
mminfo
nsrinfo
mmlocate
nsrmm
/nsr/logs
Disk-to-disk backup: NetWorker
If using regular disk, use file type device
Disk backup extra cost with options
If using virtual tape library, treat it like a
tape library
Use cloning to duplicate disk-based
backups to tape and send them offsite
Disk-to-disk backup: NetBackup
If using regular disk, use disk-based storage unit
(No extra cost for disk storage units!)
If using virtual tape library, treat it like a tape library
Use vault to duplicate disk-based backups to tape and send them offsite
What about my SAN and NAS?
SAN: LAN-free, Client-free, and Server-free backupNAS: NDMP filer to self, filer to filer, filer to server, & server to filer
Eth
ern
et
Data General
BackupServer
IBM
Backup Client
IBM
Backup Client
FC
FC
Router
Library
SCSISCSI
Disk Array
NAS Server
FCFC
FC Switchor Hub
FC
NAS Server
NAS Server
LibraryFC Switch
or Hub
FC
SCSI
Library
FC
NASSAN SAN
Virtual tape
LAN-free backups
How does this work?• SCSI Reserve/release
• Third-party queuing system
Levels of drive sharing
RestoresIBM
IBM
Disk
Disk
IBM
Disk
TapeLibrary
SCSI/FCRouter
SCSI
SCSI
SCSI
SCSI
FC
FC Switch
FC
FC
FC
How client-free backups work
Transaction Logs
TapeLibrary
DataSrvr
BackUpSrvr
B
primarydisk set
backupmirror
1
3
2a
TapeLibrary
BackUpSrvr
A2c
2b
LAN
TapeLibrary
DataSrvr
BackUpSrvr
primarydisk set
backupmirror
Transaction Logs
2
1Tape
Library
BackUpSrvr
A
LAN
Backup transaction logs to disk
Establish backup mirror
TapeLibrary
DataSrvr
BackUpSrvr
primarydisk set
backupmirror
4a 4b
Transaction Logs
1
2
3Tape
Library
BackUpSrvr
A
LAN
Split backup mirror and back it up
How client-free recoveries work
Restore backup mirror from tape
Restore primary mirror from backup mirror
Replay transaction logs from disk
TapeLibrary
DataSrvr
BackUpSrvr
primarydisk set
backupmirror
Transaction Logs
1b
2c
TapeLibrary
BackUpSrvr
A
LAN
2b
2a
1a
TapeLibrary
DataSrvr
BackUpSrvr
Transaction Logs
1
B A
4
3
25Tape
Library
BackUpSrvr
A
LAN
TapeLibrary
DataSrvr
BackUpSrvr
primarydisk set
backupmirror
Transaction Logs
TapeLibrary
BackUpSrvr
A
LAN
Server-free backups
Server directs client to take a copy-on-write snapshot
Client and server record block and file associations
Server sends XCOPY request to SAN
TapeLibrary
DataSrvr
SANw/xcopysupport
primarydisk set
backupmirror
orsnapshot
3
Transaction Logs
1
2
TapeLibrary
BackUpSrvr
A
LAN
Virtual DiskProvided byDisk Array
Block D
Block EBlock F
FileB
Block A
Block B
Block C
FileA
Server-less restoresChanging
block locations
Image levelrestores
File levelrestores
TapeLibrary
DataSrvr
SANw/xcopysupport
primarydisk set
backupmirror
orsnapshot
2
Transaction Logs
1
TapeLibrary
BackUpSrvr
A
LAN
3
4
Virtual DiskProvided byDisk Array
Block D
Block EBlock F
FileB
Block A
Block B
Block C
FileA
Tape
Snapshotor
Mirror
Block D
Block EBlock F
Block A
Block B
Block C
Virtual DiskProvided byDisk Array
Block D
Block E Block F
FileB (deleted)
Block A
Block B
Block C
FileA
Snapshotor
Mirror
Block A
Block B
Block C
Block D
Block EBlock F
Tape
Backup Restore
NDMP configurations Filer to self
Filer to filer
Filer to server
Server to filer
LAN
Filer Filer Filer
BackupServer
Tape library Tape libraryTape library
OtherServer
Server to Filer
Filerto
Self
Filer to Filer
NDMP tapelibrary
Filerto
libraryFiler toServer
Using NDMP
Level of functionality depends on the DMA
you choose
• Robotic support
• Filer-to-library support
• Filer-to-server support
• Direct access restore support
Resources
Resources
Directories of products to help you make a
better backup system
http://www.storagemountain.com
Send questions to: