Re: nvme native multipath question with two physical paths

[Wen Xiong <wenxiong@linux.ibm.com>]

On 2024-02-19 13:28, Keith Busch wrote:

> Nor should you see a /dev/nvme6n1 in this scenario. The mulitpath 
> device
> doesn't change names. It assumes the identifier from the subsystem. In
> your example, it uses subsystem '2' and will continue to use it no
> matter which controller instances are attach to it. This feature is why
> applications that have opened the /dev/nvme2n1 handle  don't need to do
> anything if the kernel experiences a path failover condition.
> 
> You should see the different paths in the hidden block hierarchy, which
> you can find in the sysfs directory. There should be an entry in your
> example at /sys/block/nvme2c6n1/. I am pretty sure  programs like
> 'iostat' can show how IO is distributed among all the paths of an nvme
> mulitpath device.

Hi Ketith,

Thanks for your detail explanation!
Wendy