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Query regarding thin device ?

In DMX 3 , If I create a thin device of 100 GB from 200 GB thin pool / data device and 100GB thin device is fully used what we need to do increase the capacity?

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Re: Query regarding thin device ?

The way to increase the size of a device is to add meta members to it.

If your 100GB device is a non-meta, you can add a (concatenated) meta member. Same applies if the device is already a concatenated meta.

If your 100GB device is a striped meta, you could do a striped meta expansion, but will need a BCV device for the process. There are good descriptions in the community on how to do a striped meta expansion.

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Re: Query regarding thin device ?

Thanks Jason for your reply. few more queries...

1) the meta device which need to be added , do we need to create from remaining 100GB of thin pool?

2) Suppose if the entire 200 GB thin pool is full, how we should add the device ? Can we increase the size of a thin pool ?

3) also do we need to enable the data protect option for the BCV device ?

Please correct me if I am wrong....

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Re: Query regarding thin device ?

Host devices (TDEVS) must be bound to a pool before they can be used and will therefore use capacity from the pool. All of the capacity of the TDEV does not need to be consumed (at device creation) as you do not need to pre-allocate the data in the pool. The host, when it writes to the device will cause the allocations to occur. This is called over-provisioning and you need to prudently manage available pool capacity if you over-provision.

A thin pool is made up from data devices (TDATS). TDATS are created from the space on the physical disk. So if all of your disks are fully populated with TDATS and all of the TDATS are enabled in your pool, then a full pool means no more space available. This situation is best avoided 🙂

If you are expanding a striped meta device using a BCV, you are correct, DATA_PROTECT=TRUE is required in order to keep the data.

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