Space Management Rick Jooss SANiSAN Business Unit

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 2 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  How a LUN fills  ONTAP Variables  Space Usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 3 What is Thin Provisioning?  Presenting more space to the servers than the storage systems actually contains  Classic examples from other industries –Banks –Water Companies –Electric Companies –Insurance Companies  Large systems are needed

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 4 Types of Thin Provisioning  Snapshot Space –Creating, mapping and snapshotting 100 x 100GB LUNs with less than 20+ TB (< 2X + Δ) –In the NAS world snapshot space is always thin provisioned  LUN Space –Creating and mapping 10TB (100 x 100GB) LUNs when the storage system only has 8TB –Only makes sense when one is not creating snapshots because having less than 10TB with snapshots is not reasonable

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 5 0% 25% 50% 75% 100% File 1 Step #1 – write 2 files, each 25% of the LUN/disk size Step #2 – write a 3 rd file which is 25% of the LUN/disk size Step #3 – delete files #1 and #2 File 2 Host reports = 50% Full Storage reports = 50% Full 0% 25% 50% 75% 100% File 1 File 2 Host reports = 75% Full Storage reports = 75% Full File 3 0% 25% 50% 75% 100% Host reports = 25% Full Storage reports = 75% Full File 3 Step #4 – write a 4th file which is 25% of the LUN/disk size 0% 25% 50% 75% 100% Host reports = 50% Full Storage reports = 100% Full File 3 File 4 LUN Filling with new files

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 6 Step #6 – delete file 3 and 4 0% 25% 50% 75% 100% Host Reports = 0% Full Storage reports = 100% Full 0% 25% 50% 75% 100% Host Reports = 25% Full Storagereports = 100% Full Step #7 – add new file 5 File 5 LUN Filling with new files

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 7 LUN Fill Percentage versus Time

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 8 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Space usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 9 ONTAP variables affecting space usage  ONTAP Variables –Guarantee –LUN reservation –Fractional (space) Reservation –Snap Reserve –Auto Delete –Auto grow –Try first

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 10 Guarantees  Set on a per volume basis  Determines when space is allocated from the aggregate  Possible settings –Volume (default) Space is reserved from the aggregate at volume creation time This space is not available to other volumes regardless of how much is really used –None No space is reserved from the aggregate at volume creation time Space is taken from the aggregate as data is written Allows thin provisioning of volumes Any individual volume still is not allowed to take more space than its size –File The same as none but allows individual LUNs (or files) to set space reservations to ensure they have adequate space

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 11 LUN Reservation  Set on per LUN basis  Determines when space is allocated from the volume  Possible settings –enabled (default) Space is reserved from the volume at LUN creation time This space is not available to other LUNs or files regardless of how much is really used –Disabled No space is reserved from the volume at volume LUN time Space is taken from the volume as data is written

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 12 Fractional (space) Reservation  Set on a per volume basis  Determines if space is reserved from the volume at first snapshot creation  Possible settings –100% (default) An amount of space equal to the amount of space used with in the LUNs is reserved from the volume This space is not available to other LUNs or files regardless of how much is really used –0 to 99% An amount of space equal to the amount of space used with in the LUNs times fractional_reserve is reserved from the volume reserved = LUN_SPACE * fractional_reserve

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 13 Available space 60GB No Snapshots 40GB LUN2: 20GB LUN1: 20GB Available space 20GB At least one snapshot fractional_reserve = GB LUN2: 20GB LUN1: 20GB At least one snapshot fractional_reserve = 60 40GB Reserve Available space 36GB 40GB LUN2: 20GB LUN1: 20GB 24GB Reserve Fractional Reserve - Example

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 14 Available space 60GB No Snapshots 40GB LUN2: 20GB LUN1: 20GB Available space 20GB At least one snapshot fractional_reserve = GB LUN2: 20GB LUN1: 20GB At least one snapshot fractional_reserve = 60 40GB Reserve Available space 48GB 40GB LUN2: 20GB LUN1: 20GB 12GB Reserve Fractional Reserve - Example

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 15 Snap Reserve  Set on a per volume basis  Determines if space is allocated from the volume for Snapshot data at volume creation time  Possible settings –20% (default for NAS) –0% (current default for SAN) –0% to 100%

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 16 Snapshot Auto Delete  Set on a per volume basis  Determines when (if) snapshots will be automatically deleted  Makes NetApp like competition but better  Possible settings –Triggers Volume Snap Reserve Space Reserve –Order delete_order – oldest, newest defer_delete – scheduled, user created, prefix, none snapmirror/dump – try, disrupt  Snapshots locked by clones, cifs or restores will not be deleted – change planned for 7.3

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 17 Volume Auto Grow  Set on a per volume basis  Determines if a volume should grow when it nearly full  Possible settings –ON -Maximum growth -Increment size –OFF  Try_first option determines whether auto_grow or auto_delete is attempted first

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 18 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Space usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 19 Available space TestLUN 20GB Step #1: Create “100GB” volume myvol df output: /vol/myvol – available 80GB /vol/myvol/.snapshot – 20GB available 80GB Available space 20GB 50GB 30GB Snapshot Available Step #2: Create 30GB LUN df output: /vol/myvol - available 50GB - used 30GB /vol/myvol/.snapshot - available 20GB - used 0 GB TestLUN Available space 20GB 50GB 30GB Snapshot Available Step #3: Write 30(+) GB to TestLUN df output: /vol/myvol - available 50GB - used 30GB /vol/myvol/.snapshot - available 20GB - used 0 GB Space Usage in a volume

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 20 Reserve Step #4: Create snapshot #1 df output: /vol/myvol - available 20GB - used 60GB /vol/myvol/.snapshot - available 20GB - used 0 GB TestLUN Available space 20GB 30GB Snapshot Available 20GB Reserve Step #5: Overwrite first 10GB of TestLUN df output: /vol/myvol - available 20GB - used 60GB /vol/myvol/.snapshot - available 10GB - used 10 GB TestLUN Available space 10GB 30GB Snapshot used 20GB 10GB Snapshot Avail Reserve Step #6: Overwrite second 10GB of TestLUN df output: /vol/myvol - available 20GB - used 60GB /vol/myvol/.snapshot - available 0GB - used 20 GB TestLUN Available space 20GB 30GB Snapshot Used 20GB Space Usage in a volume

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 21 Reserve Step #7: Overwrite last 10GB of TestLUN df output: /vol/myvol - available 10GB - used 70GB /vol/myvol/.snapshot - available 0GB - used 30 GB TestLUN Available space 10GB 30GB Snapshot used Step #9: Create snapshot #2 df output: /vol/myvol - available 10GB - used 70GB /vol/myvol/.snapshot - available 0GB - used 30 GB 30GB Reserve TestLUN Available space 10GB 30GB Snapshot used 30GB Reserve Step #8: Re-overwrite another 10GB of TestLUN df output: /vol/myvol - available 10GB - used 70GB /vol/myvol/.snapshot - available 0GB - used 30 GB TestLUN Available space 10GB 30GB Snapshot used 30GB Space Usage in a volume

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 22 Reserve Step #10: Overwrite first 10GB of TestLUN df output: /vol/myvol - available 0GB - used 80GB /vol/myvol/.snapshot - available 0GB - used 40 GB TestLUN 30GB Snapshot used Step #12: Overwrite another 10GB of TestLUN df output: /vol/myvol - available 0GB - used 80GB /vol/myvol/.snapshot - available 0GB - used 50 GB 40GB Reserve TestLUN 30GB Snapshot used 50GB Reserve Step #11: Create snapshot #3 Fails because there is no free space in the volume TestLUN 30GB Snapshot used 40GB Space Usage in a volume

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 23 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Space usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 24 Space Management – Default Configuration  Default Configuration: –Guarantee= volume –LUN reservation = on –Fractional_reserve= 100% –Snap_reserve= 0% –Auto_delete= off –Auto_grow= off –Try_first= NA Reserve TestLUN Available space 30GB 40GB

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 25 Space Management – Default Configuration  Positives –Easy to manage/monitor space Running “out” of space only results in no additional snapshots being created SnapShots and active LUNs will always be available –Volumes are independent of each other  Negatives –Requires 2X + Δ space requirement

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 26 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Space usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 27 Thin Provisioning Snapshot Space - Autodelete  Auto Delete Configuration: –Guarantee= volume –LUN reservation = on –Fractional_reserve= 10% –Snap_reserve= 0% –Auto_delete= volume –Auto_grow= off –Try_first= snap_delete TestLUN Available space 60GB 30GB Reserve 10GB

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 28 Thin Provisioning Snapshot Space - Autodelete  Positives –Easy to monitor/understand space just volume –Sacrifices snapshots before active LUNs –Volumes are independent of each other –Looks like the competition  Negatives –Doesn’t use shared space from the aggregate –Until ONTAP 7.3 have to be cautious with using FlexClones

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 29 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 30 Thin Provisioning Snapshot Space – Autogrow  Auto Grow Configuration: –Guarantee= volume –LUN reservation = on –Fractional_reserve= 10% –Snap_reserve= 0% –Auto_delete= volume –Auto_grow= on –Try_first= auto_grow

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 31 Thin Provisioning Snapshot Space – Autogrow  Positives –Uses shared free space from the aggregate for possible growth –Sacrifices snapshots before active LUNs –Can tune amount of thin provisioning per volume –Works even with a smaller number of volumes  Negatives –Volumes are not completely independent of one another Always the case when using shared free space Growth in one volume can limit growth of another

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 32 Autogrow Example - Starting Point volume used / size / consumed vol1 = 0 / 100 / 100 vol2= 0 / 100 / 100 vol3= 0 / 100 / total= 0 / 300 / 300 free= 30

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 33 Autogrow Example - After volume growth  Single volume grows to 120GB volume used / size / consumed vol1 = 90 / 100 / 100 vol2= 120 / 120 / 120 vol3= 50 / 100 / total= 260 / 320 / 320 free= 10

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 34 Autogrow Example - After another volume grows  Single volume grows to 120GB  Another volume grow to 110GB  Aggregate is now full volume used / size / consumed vol1 = 110 / 110 / 110 vol2= 120 / 120 / 120 vol3= 60 / 100 / total= 290 / 330 / 330 free= 0

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 35 Autogrow Example – After freeing space  Space is freed within the volume - manual snapshot deletion  Volume is manually resized volume used / size / consumed vol1 = 110 / 110 / 110 vol2= 110 / 110 / 110 vol3= 60 / 100 / total= 0 / 320 / 320 free= 10

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 36 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Space usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 37 Thin Provisioning Snapshot Space Guarantee = none  None Guarantee Configuration: –Guarantee= none –LUN reservation = on –Fractional_reserve= 0% –Snap_reserve= 0% –Auto_delete= volume –Auto_grow= off –Try_first= auto_delete

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 38  Positives –Uses shared space from the aggregate  Negatives –Volumes are not independent of one another –Activity in some volumes can cause all volumes with a none guarantee to go offline –Generally only makes sense with a large number of volumes Thin Provisioning Snapshot Space Guarantee = none

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 39 volume used / size / consumed vol1 = 0 / 150 / 0 vol2= 0 / 150 / 0 vol3= 0 / 150 / total= 0 / 450 / 0 free= 330  At volume creation no space is allocated from the aggregate Thin Provisioning Snapshot Space Guarantee = none

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 40 volume used / size / consumed vol1 = 40 / 150 / 40 vol2= 100 / 150 / 100 vol3= 100 / 150 / total= 240 / 450 / 240 free= 90 Thin Provisioning Snapshot Space Guarantee = none

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 41 volume used / size / consumed vol1 = 90 / 150 / 90 vol2= 120 / 150 / 120 vol3= 120 / 150 / total= 330 / 450 / 330 free= 0  Highlights both the advantage and disadvantage of a none guarantee –Allows vol2 and vol3 to use space which vol1 is not using –If any volume consumes more space all volume with a guarantee of none are going to go offline on the next write Thin Provisioning Snapshot Space Guarantee = none

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 42 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Space usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 43 Thin Provisioning LUNs – Guarantee = NONE  Guarantee = none configuration: –Guarantee= none –LUN reservation = on –Fractional_reserve= NA (no snapshots) –Snap_reserve= 0% (no snapshots) –Auto_delete= snap_reserve (safety measure) –Auto_grow= off –Try_first= snap_delete

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 44 Thin Provisioning LUNs – Guarantee = NONE  Positives –Uses shared free space from the aggregate –Works with SDW without issues  Negative –Limited by BURT Not possible to configure a LUN larger than actual free space in the aggregate For example, aggregate has 200GB free and you create a 400GB volume –It is possible to create 2 x 200GB or 4 x 100GB –It is not possible to create 1 x 201GB LUN

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 45 Agenda  What is Flexible or Thin Provisioning  Types of Thin Provisioning  ONTAP Variables  Space usage in a volume  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 46 Thin Provisioning LUNs – reservation disabled  LUN reservation disabled configuration: –Guarantee= volume –LUN reservation = off –Fractional_reserve= NA (no snapshots) –Snap_reserve= 0% (no snapshots) –Auto_delete= snap_reserve (safety measure) –Auto_grow= on –Try_first= autodelete

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 47 Thin Provisioning LUNs – reservation disabled  Positives –Volumes are independent of one another –Amount of thin provisioning can be tuned per volume  Negative –Doesn’t currently work with SDW With Data ONTAP DSM 3.0, SDW is not needed for multipathing Casablanca (May 2007) will support this!!

Restricted to NetApp Employees & NDA Channel Partners. Copyright (c) 2006 Network Appliance, Inc. All rights reserved. 48 Agenda - Summary  Configurations –Default Configuration –Snapshot - Snapshot Auto delete –Snapshot - Volume Auto grow –Snapshot - Volume guarantee none –LUN - Volume guarantee none –LUN - LUN reservation disabled