An administrator has a VM that consumes large amounts of storage and has the following...

Erasure coding is a method of data protection in which data is broken into fragments, expanded and encoded with redundant data pieces, and stored across a set of different locations or storage media. The goal of erasure coding is to enable data that becomes corrupted at some point in the disk storage process to be reconstructed by using information about the data that’s stored elsewhere in the array1.

In the context of Nutanix, erasure coding increases the usable capacity on a cluster. Instead of replicating data, erasure coding uses parity information to rebuild data in the event of a disk failure1. The capacity savings of erasure coding is in addition to deduplication and compression savings1.

Given the characteristics of the VM in the question (large/sequential writes, data kept for years, data accessed only at the end of the year), Post-Process Compression would be the most suitable feature to utilize to save space. This is because Post-Process Compression, as the name suggests, compresses data after it has been written to the storage, which is suitable for data that is not accessed frequently2.

References:

Erasure Coding | Nutanix Community

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