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Disable Multipath for Identical NVMe Drives on Ubuntu Server

I have 4 identical NVMe drives installed in my system.

Ubuntu treats them as one “multipath” device by default. This is not accurate.

I posted something on Ubuntu Forums, but no response at time of writing. (2021-02-18)

Here’s the problem:

lsblk    
 nvme0n1                   259:0    0   1.9T  0 disk  
 └─mpatha                  253:1    0   1.9T  0 mpath 
 nvme1n1                   259:1    0   1.9T  0 disk  
 └─mpatha                  253:1    0   1.9T  0 mpath 
 nvme2n1                   259:2    0   1.9T  0 disk  
 └─mpatha                  253:1    0   1.9T  0 mpath 
 nvme3n1                   259:3    0   1.9T  0 disk  
 └─mpatha                  253:1    0   1.9T  0 mpath 

The fix is relatively simple. It is outlined in some SUSE Documentation.

#/etc/multipath.conf

blacklist {
       devnode "^nvme[0-9]"
 }

Once the config file has been changed, apply the changes according to the Ubuntu Server Documentation.

sudo systemctl restart multipathd

And all is good!

lsblk
 nvme0n1                   259:0    0   1.9T  0 disk 
 nvme1n1                   259:1    0   1.9T  0 disk 
 nvme2n1                   259:2    0   1.9T  0 disk 
 nvme3n1                   259:3    0   1.9T  0 disk