What is storage pool in EMC? A storage pool is a set of disks that provide specific storage characteristics for the resources that use them. When multiple pools are configured, you can choose which pool to use when you create new storage resources.
What is a storage pool?
A storage pool is a general term used for RAID groups and pools. A pool is a set of disks, all with the same redundancy (RAID 5, RAID 6, and RAID 1/0) on which you create one or more Logical Unit Numbers (LUNs). Two storage pools are created: Exchange DB and Exchange Logs with RAID 1/0 type redundancy near-line SAS (NL SAS) drives.
How to create a fast cache?
To create a FAST Cache, click the FAST Cache tab in the Storage System Properties window to view FAST Cache information ( Figure 1 ). If the FAST Cache has not been created on the storage system, the Create button in the bottom of the dialog box is enabled. The Destroy button is enabled when the FAST Cache has been created. Fast Cache is enabled on EMC VNX5500 storage.
What is fast cache?
This feature is called FAST Cache. At a system level, FAST Cache helps make the most efficient use of flash drive capacity. FAST Cache does this by using flash drives for the most frequently accessed data in the storage system instead of dedicating flash drives to a particular application. FAST Caches are also enabled on storage pools and allow you to leverage the lower response time and better IOPS of flash drives without dedicating flash drives to a specific application. Because of this implementation, flash drives need not be dedicated to specific applications. Instead, their performance is leveraged in the caching tier, improving performance for any application accessing the storage array. FAST Cache adjusts to a hot spot anywhere in the array so you no longer need to analyze specific application requirements. It provides better performance to all applications in the storage systems while using fewer dedicated flash drives. A set of flash drives is selected either automatically by the storage system or manually by the user. By default, after you have installed the FAST Cache enabler, FAST cache is enabled on new RAID group LUNs and storage pools. When a FAST cache has been created, the storage system automatically promotes frequently accessed chunks of data to the FAST cache to improve application performance.
Why export NFS pool?
Once the NFS pool is created, you must export the pool in order to make the file system or directories available to NFS clients. To do this:
Where are NFS pools created?
NFS pools are created from the storage pool section of EMC Unisphere. In this example, we are going to use a storage pool called NFS Pool ( Figure 18 ).
What is a VNX?
The VNX is a multiprotocol machine that provides access to data through the Network File System (NFS) protocol. NFS is a client/server distributed file service that provides file sharing in network environments. The NFS protocol enables the VNX to assume the functions of an NFS server. NFS environments typically include:
What happens when you export NFS?
Once you export NFS, the directories contained in the NFS will be available for mounting on the application servers.
What drives are included in a heterogeneous pool?
As mentioned previously, heterogeneous pools can consist different types of drives. VNX supports Flash, SAS, and NL-SAS drives in one pool. Heterogeneous pools provide the infrastructure for FAST VP ( Fully Automated Storage Tiering for Virtual Pools ).
How many drives can be in a VNX RAID group?
Within EMC VNX RAID groups should have a maximum count of 16 drives (which is strange, since this rule does not apply to NetApp at all!).#N#Choosing the correct drive type is only one step, you also have to choose a correct RAID group.
What is storage pool?
A storage pool is somehow analogous to a RAID group. In few words it’s a physical collection of disks on which logical units (LUNs) are created. Pools are dedicated for use by pool (thin or thick) LUNs. Where R AID group can only contain up to 16 disks, pool can contain hundreds of disks.
Why is a pool the same as a RAID group?
Of course pool has the same level of protection against disk failure as RAID groups, simply because RAID groups are used to build up pool. In fact, during pool creation, you have to choose which RAID configuration you preffer. Pools can be homogeneous or heterogeneous.
Which RAID is used for NL SAS?
And it’s much more space effective, since blocks are not mirrored, and parity takes only one extra disk (distributed on all disks thru the RAID group) RAID 6 – Most often used for NL-SAS. Works best with read-based workloads such as archiving and backup to disk.
How many disks can a VNX5500 use?
Depends on the VNX model you can use limited number of disks at once, for example maximum number of disks with VNX5500 is 80, so if you would like to create a pool from 120 disks you need to first create a pool using 80 disks, and then expand this pool with additional 40 disks.
How to expand RAID group?
You can easily expand RAID Group, and Pools. To do so, you need to have extra hard drives available. Right-click on the pool, and select Expand.
Can you shrink a RAID pool?
As with RAID groups, the same is with Pools, you cannot shrink the pool. To release some space you would have to completly destroy the pool.
What is the name of the game where you put balls on the rails?
Pool, also more formally known as pocket billiards (mostly in North America) or pool billiards (mostly in Europe and Australia), is the family of cue sports and games played on a pool table having six receptacles called pockets along the rails, into which balls are deposited as the main goal of play.
What are some examples of storage devices?
Magnetic discs, tapes, and DVDs are an example of storage devices. Hard drives, CD-ROM and DVD-ROM drives, floppy drives, and tape drives are examples of storage devices. You can read data from the storage medium, but you CANNOT modify the data or save new data to it.
What is storage device?
definition: storage devices - Any device used to store other items. Tupperware containers are storage devices. A hard disk drive on a computer is a storage device meant to store information. An attic is a storage device built into your home. A trunk in a car is meant as a storage device for luggage, spare tire and tools, etc.
What is a vernal pool?
Continue Reading. A vernal pool is a body of water that forms in the spring but dries up later in the year. Because vernal pools cannot support fish, they have ecosystems with many organisms that do not live outside vernal pools.
What are the two kinds of capacity gadgets?
There are two sorts of capacity gadgets utilized with PCs: an essential stockpiling gadget, similar to RAM, and an optional stockpiling gadget, similar to a hard drive. Auxiliary stockpiling can be removable, inner or outside. Related Answer. Larye Parkins.
Is information stockpiling worth it?
Information stockpiling is an electromagnetic spot where PC processors can get to it . If you don't have room to protect your home investment, a storage unit might be worth it. Again, you need to run a cost-benefit analysis. If you really like a collection or item you already own and can afford a storage unit, do so.
What is the target size of a thin provisioned storage resource?
Unisphere reserves only a portion of the requested size, called the initial allocation. The requested size of the storage resource represents a subscribed quantity. Thin-provisioned LUNs do not have an initial allocation. For thin-provisioned file systems, the initial allocation is 3 GB. Additional storage is allocated on-demand.
What is subscribed space?
The subscribed space used is the percentage of the pool's total space that has been requested by its associated storage resources. When this value is over 100%, the pool is oversubscribed.
What does it mean when a file is full?
A thin-provisioned file-based storage resource may appear full when data copied or written to the storage resource is greater than the space available at that time. When this occurs, the system begins to automatically extend the storage space and accommodate the write operation. Try the write operation again. As long as there is enough extension space available, this operation will complete successfully.
Does Unisphere support thin provisioned storage?
All pools support thin-provisioned storage resources. For thin-provisioned storage resources, only incremental portions of the size are allocated based on usage. Because thin-provision ed storage resources can subscribe to more storage than is actually available to them, pools can be over-provisioned to support more storage capacity than they actually possess. Unisphere automatically generates notification messages when total pool usage reaches 85% of the pool's physical capacity. (You can customize this threshold).
What is a RG in a CLARIION?
So, on a CLARiiON the most basic structure (ignoring the physical drive itself) when building LUNs is your RAID Group (RG). This is true for traditional RGs AND Storage Pools. For Storage Pools you don't create the RGs yourself and you don't see them, but they are there underlying the Pool structure.
How many drives can you have in a storage pool?
A basic Storage Pool can be made up of many more drives than a traditional RG. Instead of being limited to 16 drives in an RG you could potentially have hundreds of drives in a single pool.
How many drives can you put in a RG?
You can increase the capacity of the RG as a whole by adding drives into the RG (up to a limit of 16 drives - although that isn't usually recommended). You can't increase the size of the LUN though without doing some interesting shuffling (e.g. binding MetaLUN).
Can you create RGs in a storage pool?
For Storage Pools you don 't create the RGs yourself and you don't see them, but they are there underlying the Pool structure. A traditional RAID Group is simply a set of physical drives that have been grouped together so that LUNS can be "bound" with a specific RAID type.
Can you increase the size of a LUN?
There is one exception to this if you have a single LUN consuming an entire RG - you can increase the size of the LUN as you add drives to the RG. You are also limited to the IO performance limits of the RG unless you build MetaLUN structures across multiple RGs.
Is there a place for RGs?
And while it may appear that there would be no place for RGs any more, that is still far from true. They still provide the only way to absolutely guarantee specific performance characteristics for critical applications. In general though Storage Pools are more flexible, more efficient, and easier to manage.
Can you use fast cache with pool?
FAST Cache comes into play by allowing a reaction to changes in I/O patterns between relocation windows. FAST and FAST Cache can be used together or seperately based on your needs.
