These are the three different variants of Ontap 9 software, introduced with Ontap 9 version. Please note - NetApp's flagship OS “Clustered Data ONTAP” is now simply called “ONTAP”, and the new release is called “ONTAP 9”.
Ontap 9 = FAS systems [Controller + NetApp Disk Shelves] - True traditional HA, no mirroring of aggregates, as each node sees partners disks.
Ontap 9 Select = Commodity Hardware [software-defined version of ONTAP, runs on top of Non-NetApp storage] - Emulated HA with mirroring of aggregates.
Ontap 9 Cloud = AMAZON, AZURE [Ontap OS as service] - Cloud HA - mirroring of aggregates.
My curiosity was mainly focused around this question - How does HA works with commodity Hardware [Private cloud] and Cloud based [Public Cloud] storage.
Let's try to understand the difference between traditional HA vs Ontap Cloud/Select HA?
Traditional HA : This HA only applies to FAS systems where Ontap runs on top of NetApp controller attached Disk shelves.
The basic concept behind traditional HA is - Both Controllers see the Disks, in other words, you attach each controller to:
1. It's own Disk Shelves
2. To partner Disk Shelves
Plus, there is HA NVRAM Interconnect [Infiband] that continuously mirrors partners NVRAM log.
NetApp FAS Arrays [Basically NetApp Provided Storage] use specialized hardware to pass information between HA pairs in an ONTAP cluster.
Software-defined environments [ONTAP Select], however, do not tend to have this type of equipment available (such as Infiniband ), so an alternate solution is needed. Although several possibilities were considered, ONTAP requirements placed on the interconnect transport required that this functionality be emulated in software.
As a result, within an ONTAP Select cluster, the functionality of the HA interconnect (traditionally provided by hardware) has been designed into the OS, using Ethernet as a transport mechanism.
For ONTAP select HA, you can read this TR:
http://www.netapp.com/us/media/tr-4517.pdf
Cloud HA: Here, again there is no NetApp Hardware or controller, just the Ontap software as service. Hence, there is no question of cabling the Disk Shelves to each other, b'cos the Storage is provided by the Cloud Provider.
The basic concept behind cloud/Select HA is - Storage is not shared between nodes. Instead, data is synchronously mirrored between the nodes so that the data is available in the event of failure. Basically additional storage space is needed for mirroring.
Example - When you create a new volume, Cloud Manager allocates the same number of disks to both nodes, and creates a mirrored aggregate, and then creates the new volume. For example, if two disks are required for the volume, Cloud Manager allocates two disks per node for a total of four disks.
Note: Clients should access volumes by using the floating IP address of the node on which the volume resides. If clients access a volume using the floating IP address of the partner node, traffic goes between both nodes, which reduces performance.
For ONTAP Cloud HA:
https://library.netapp.com/ecmdocs/ECMLP2484726/html/GUID-62F55FF3-9D4A-4C77-8F1D-C0CB7268051B.html
For Ontap 9 features:
https://whyistheinternetbroken.wordpress.com/2016/06/23/ontap9rc1-available/
For Ontap 9.1 features:
https://whyistheinternetbroken.wordpress.com/2017/01/12/ontap-91-ga/
Ontap 9 = FAS systems [Controller + NetApp Disk Shelves] - True traditional HA, no mirroring of aggregates, as each node sees partners disks.
Ontap 9 Select = Commodity Hardware [software-defined version of ONTAP, runs on top of Non-NetApp storage] - Emulated HA with mirroring of aggregates.
Ontap 9 Cloud = AMAZON, AZURE [Ontap OS as service] - Cloud HA - mirroring of aggregates.
My curiosity was mainly focused around this question - How does HA works with commodity Hardware [Private cloud] and Cloud based [Public Cloud] storage.
Let's try to understand the difference between traditional HA vs Ontap Cloud/Select HA?
Traditional HA : This HA only applies to FAS systems where Ontap runs on top of NetApp controller attached Disk shelves.
The basic concept behind traditional HA is - Both Controllers see the Disks, in other words, you attach each controller to:
1. It's own Disk Shelves
2. To partner Disk Shelves
Plus, there is HA NVRAM Interconnect [Infiband] that continuously mirrors partners NVRAM log.
NetApp FAS Arrays [Basically NetApp Provided Storage] use specialized hardware to pass information between HA pairs in an ONTAP cluster.
Software-defined environments [ONTAP Select], however, do not tend to have this type of equipment available (such as Infiniband ), so an alternate solution is needed. Although several possibilities were considered, ONTAP requirements placed on the interconnect transport required that this functionality be emulated in software.
As a result, within an ONTAP Select cluster, the functionality of the HA interconnect (traditionally provided by hardware) has been designed into the OS, using Ethernet as a transport mechanism.
For ONTAP select HA, you can read this TR:
http://www.netapp.com/us/media/tr-4517.pdf
Cloud HA: Here, again there is no NetApp Hardware or controller, just the Ontap software as service. Hence, there is no question of cabling the Disk Shelves to each other, b'cos the Storage is provided by the Cloud Provider.
The basic concept behind cloud/Select HA is - Storage is not shared between nodes. Instead, data is synchronously mirrored between the nodes so that the data is available in the event of failure. Basically additional storage space is needed for mirroring.
Example - When you create a new volume, Cloud Manager allocates the same number of disks to both nodes, and creates a mirrored aggregate, and then creates the new volume. For example, if two disks are required for the volume, Cloud Manager allocates two disks per node for a total of four disks.
Note: Clients should access volumes by using the floating IP address of the node on which the volume resides. If clients access a volume using the floating IP address of the partner node, traffic goes between both nodes, which reduces performance.
For ONTAP Cloud HA:
https://library.netapp.com/ecmdocs/ECMLP2484726/html/GUID-62F55FF3-9D4A-4C77-8F1D-C0CB7268051B.html
For Ontap 9 features:
https://whyistheinternetbroken.wordpress.com/2016/06/23/ontap9rc1-available/
For Ontap 9.1 features:
https://whyistheinternetbroken.wordpress.com/2017/01/12/ontap-91-ga/
Please Note: The information provided on this subject is based purely on my understanding, for corrections please feel free to leave your comments.
No comments:
Post a Comment