Recognizing SMR HDDs

Gary Jennejohn gljennjohn at
Thu May 26 06:43:06 UTC 2016

Now that ken@ has checked in the SMR code I'm wondering how I can see
whether it's having any effect.

I have a 8TB SMR disk in a USB3 enclosure.  Does the kernel emit any
sort of trace to indicate that it sees the drive as SMR and takes
that into account?

I have the probe trace enabled in my kernel config, but I don't see
anything special pop out when I turn the drive on.

Does the fact that the drive appears as a /dev/daX play any role?

BTW the disk returns an error when multiple LUNs are probed.

Gary Jennejohn

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