The basic concept of snapshot to network storage. Qsan is a RAID system expert providing iSCSI IP SAN as well as Unified Storage, Fibre Channel, SAS and FCoE storage. Visit us at www.QsanTechnology.com

1. Snapshots for Network Storage
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2. What is Snapshot?
- General Idea
 A “picture” of the disk, taken at a specific time point
 Used on Virtual Disks
2

3. What is Snapshot?
- General Idea
 A “picture” of the disk, taken at a specific time point
 Used on Virtual Disks
Original Snapshot 1 Snapshot 2
Timeline
3

4. What is Snapshot?
- General Idea
 A “picture” of the disk, taken at a specific time point
 Used on Virtual Disks
What is it for?
 Fast, space saving backup
 Quick review of data history
 Allows more precious restore points and frequent
backup missions
 Not suitable for critical backup purposes
 Temporary data protection when modifying data
4

5. How does it work?
- Copy on Write technique
 A space saving data backup technique that makes a
copy of the original data only if it’s modified.
5

6. How does it work?
- Copy on Write technique
 A space saving data backup technique that makes a
copy of the original data only if it’s modified.
A
Original Data (VD) Copy (Snapshot)
6

7. How does it work?
- Copy on Write technique
 A space saving data backup technique that makes a
copy of the original data only if it’s modified.
Writes B to replace A
A
Original Data (VD) Copy (Snapshot)
7

8. How does it work?
- Copy on Write technique
 A space saving data backup technique that makes a
copy of the original data only if it’s modified.
Writes B to replace A
Copy
A A
Original Data (VD) Copy (Snapshot)
8

9. How does it work?
- Copy on Write technique
 A space saving data backup technique that makes a
copy of the original data only if it’s modified.
Writes B to replace A
Copy
B
A A
Original Data (VD) Copy (Snapshot)
9

10. How does it work?
- Snapshots establishment
Timeline
10

11. How does it work?
- Snapshots establishment
Timeline
VD at 2PM
A B C D
11

12. How does it work?
- Snapshots establishment
Snapshot1 at
2:00 PM
Timeline
VD at 2PM
A B C D
12

13. How does it work?
- Snapshots establishment
No
Changes
Snapshot1 at
2:00 PM
Timeline
VD at 2PM
A B C D
13

14. How does it work?
- Snapshots establishment
No
Changes
Snapshot1 at
2:00 PM
No Changes
Timeline
VD at 2PM VD at 3PM
A B C D A B C D
14

15. How does it work?
- Snapshots establishment
No
Changes
Snapshot1 at Snapshot2 at
2:00 PM 3:00 PM
No Changes
Timeline
VD at 2PM VD at 3PM
A B C D A B C D
15

16. How does it work?
- Snapshots establishment
Replaces
No B with E
Changes Replaces
Snapshot1 at Snapshot2 at D with F
2:00 PM 3:00 PM
No Changes
Timeline
VD at 2PM VD at 3PM
A B C D A B C D
16

17. How does it work?
- Snapshots establishment
Replaces
No B with E
Changes Replaces
Snapshot1 at Snapshot2 at D with F
2:00 PM 3:00 PM
No Changes B D
Timeline
VD at 2PM VD at 3PM
A B C D A B C D A E C F
17

18. How does it work?
- Snapshots establishment
Replaces
No B with E
Changes Replaces
Snapshot1 at Snapshot2 at D with F Snapshot3 at
2:00 PM 3:00 PM 4:00 PM
No Changes B D
Timeline
VD at 2PM VD at 3PM
A B C D A B C D A E C F
18

19. How does it work?
- Snapshots establishment
Replaces Replaces
No B with E A with G
Changes Replaces Replaces
Snapshot1 at Snapshot2 at D with F Snapshot3 at C with H
2:00 PM 3:00 PM 4:00 PM
No Changes B D
Timeline
VD at 2PM VD at 3PM
A B C D A B C D A E C F
19

20. How does it work?
- Snapshots establishment
Replaces Replaces
No B with E A with G
Changes Replaces Replaces
Snapshot1 at Snapshot2 at D with F Snapshot3 at C with H
2:00 PM 3:00 PM 4:00 PM
No Changes B D A C
Timeline
VD at 2PM VD at 3PM
A B C D A B C D A E C F G E H F
20

21. How does it work?
- Snapshots establishment
Replaces Replaces
No B with E A with G
Changes Replaces Replaces
Snapshot1 at Snapshot2 at D with F Snapshot3 at C with HSnapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
No Changes B D A C
Timeline
VD at 2PM VD at 3PM
A B C D A B C D A E C F G E H F
21

22. How does it work?
- Snapshots establishment Futur
Replaces Replaces
No B with E A with G e
Changes Replaces Replaces chang
Snapshot1 at Snapshot2 at D with F Snapshot3 at C with HSnapshot4 at es
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM
A B C D A B C D A E C F G E H F
22

23. How does it work?
- Snapshots establishment Futur
Replaces Replaces
No B with E A with G e
Each snapshot records accumulated changes until next snapshot is takenchang
Changes Replaces Replaces
Snapshot1 at Snapshot2 at D with F Snapshot3 at C with HSnapshot4 at es
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F G E H F
23

24. Rollback Snapshots
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F G E H F
24

25. Rollback Snapshots
Rollback from
5PM to 4PM
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F G E H F
25

26. Rollback Snapshots
Rollback from
5PM to 4PM
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F A
G E C
H F
26

27. Rollback Snapshots
Rollback from
5PM to 4PM
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F A
G E C
H F
27

28. Rollback Snapshots
Rollback from
5PM to 3PM
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F A
G E C
H F
28

29. Rollback Snapshots
Rollback from
5PM to 3PM
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F A
G E B
C
H F D
29

30. Rollback Snapshots
Rollback from
5PM to 3PM
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F A
G E B
C
H F D
30

31. Rollback Snapshots
1. Restoring recorded changes in order
2. Only older snapshots are kept after rollback
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F A
G E B
C
H F D
31

32. Delete Snapshots
 Consider dependencies before deleting snapshots.
 Snapshots taken earlier will be deleted along with the
target snapshot.
32

33. Snapshots Dependencies
When delete snapshots…
Delete a snapshot involves deletion of earlier ones
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
Future
No Changes B D A C Changes
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F G E H F
33

34. Snapshots Dependencies
When rollback snapshots…
Depe Depe Dep
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM nds 3:00 PM nds 4:00 PM ends 5:00 PM
On On On
B D A C
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F G E H F
34

35. Snapshots Dependencies
When rollback snapshots…
Lack of snapshots in-between makes it impossible
to roll back to the target
Snapshot1 at Snapshot2 at Snapshot3 at Snapshot4 at
2:00 PM 3:00 PM 4:00 PM 5:00 PM
B D A C
Timeline
VD at 2PM VD at 3PM VD at 4PM VD at 5PM
A B C D A B C D A E C F G E H F
35

36. TrioNAS LX U600Q
 Outstanding Performance  Advanced Protection
o Hardware RAID o Snapshot
o SSD caching o Volume clone
o Qsan Unified OS o Battery Backup Module
o AntiVirus
 Integrated Backup Solution  Storage Efficiency
o Amazon S3 Cloud backup o Thin Provisioning, DeDup, Compression
o Remote Replication o UnifiedAUTH
36

37. AegisSAN LX P600Q (iSCSI)
 10GbE iSCSI-6G SAS High Availability Systems  Outstanding Performance
 Intel Xeon Dual core CPU, Intel® Ethernet  QiSOE (Qsan Hardware iSCSI
10GbE offload engine)
 Dual Active controllers, and full redundant  Up to 640K IOPS, up to 4,000
and hot-pluggable design MB/s throughput
 2x 10GbE + 2x 1GbE iSCSI ports per controller
 SBB form factor, 4U24/3U16/2U12/2U24
 Support RAID 0, 1, 0+1, 3, 5, 6, 10, 30, 50, 60,
JBOD, N-way mirror, online volume
expansion 37

38. AegisSAN LX F600Q (Fibre Channel)
 8GbE FC-6G SAS High Availability Systems  Outstanding Performance
 Intel Xeon Dual core CPU  Up to 650K IOPS, up to 5,000
 Dual Active controllers, and full redundant and MB/s throughput
hot-pluggable design
 4x 8G FC + 2x 1GbE iSCSI ports per controller
 SBB form factor, 4U24/3U16/2U12/2U24
 Support RAID 0, 1, 0+1, 3, 5, 6, 10, 30, 50, 60,
JBOD, N-way mirror, online volume expansion
38

39. QsanTechnology.com
Sales@QsanTechnology.com
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