lun block size

Ashun — Fri, 17 Jan 2025 07:04:44 GMT

I have a question,
This KB mentions: The default disk block size for WAFL is 4k, which is equal to LUN's physical block size
But when I use lun show-fields block-size, I get a different result. Am I wrong?

KB：

Which command is used to display the physical block size of LUN? - NetApp Knowledge Base

Re: lun block size

chamfer — Wed, 22 Jan 2025 00:27:26 GMT

Hi @Ashun ,

Traditional block size advertised by hard disks is 512 bytes.
NetApp LUNs use a larger block size to store data while continuing to advertise smaller 512 byte blocks to the host for compatibility purposes.
Advertised blocks are referred to as logical blocks and underlying storage block is referred to as a physical block.
NetApp LUN stores data in 4 KB physical blocks, which yields eight 512 byte logical blocks per physical block.

Reference: https://kb.netapp.com/on-prem/ontap/da/SAN/SAN-KBs/How_to_identify_unaligned_IO_on_LUNs

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lun block size

Re: lun block size