[Discuss] Help with I/O errors on RAID array?

[dbarrett at blazemonger.com (Daniel Barrett)]

On October 13, 2025, markw at mohawksoft.com wrote:
>Look at /var/log/messages and/or run "dmesg" and look for I/O errors. It
>should show you which drive is failing.

Thanks. dmesg hasn't provided any information about any disk errors so far:

  $ sudo dmesg|grep nvm
  [    3.279193] nvme nvme0: pci function 0000:01:00.0
  [    3.280193] nvme nvme1: pci function 0000:43:00.0
  [    3.286725] nvme nvme1: missing or invalid SUBNQN field.
  [    3.286725] nvme nvme0: missing or invalid SUBNQN field.
  [    3.287359] nvme nvme0: Shutdown timeout set to 8 seconds
  [    3.287821] nvme nvme1: Shutdown timeout set to 8 seconds
  [    3.316978] nvme nvme0: 32/0/0 default/read/poll queues
  [    3.317747] nvme nvme1: 32/0/0 default/read/poll queues
  [    3.324548]  nvme0n1: p1
  [    3.326850]  nvme1n1: p1

  $ sudo dmesg|grep -w md1
  [    4.207982] md/raid1:md1: active with 2 out of 2 mirrors
  [    4.223497] md1: detected capacity change from 0 to 3906762752
  [    4.224742]  md1: p1

/var/log/syslog has no errors either, except for the usual "I don't
understand the SMART code you just sent me" errors that happen on
every boot:

  Oct 12 11:57:55 myhost smartd[2197]: Device: /dev/nvme0, number of Error 
Log entries increased from 176 to 179
  Oct 12 11:57:55 myhost smartd[2197]: Device: /dev/nvme1, number of Error 
Log entries increased from 143 to 146

Dan