Q4OS Forum

magenta-cuda

Member

Registered: 2022-01-06

Posts: 22

mdadm: No arrays found in config file or automatically

32-bit Q4OS Trinity (Distro: Q4OS 4.7.1-n1) works quite well for me and has become my daily driver. However, there are some annoyances that I have not been able to solve. It takes several minutes to boot. Part of the problem may be related to the boot time message:

    mdadm: No array found in config file or automatically

This message is displayed multiple times (~20) at the start of the boot process. I did a google search and mdadm is for Linux RAID. However, I am not using RAID and I don't understand why mdadm is running.

I don't think this is relevant but the partition created by the installer did not have a ldlinux.sys so I manually installed it using extlinux other than that I believe my installation process was normal. There is another anomaly that seems to slowing down the boot process but I will create a separate topic for it.

magenta-cuda

Member

Registered: 2022-01-06

Posts: 22

Re: mdadm: No arrays found in config file or automatically

I now understand why this happens. I originally ran Q4OS from a USB flash drive. But, since I now use it as my daily driver I moved it to my hard disk. This hard disk has 20 partitions. The following excerpt from /etc/mdadm/mdadm.conf explains what is happening:

# by default (built-in), scan all partitions (/proc/partitions) and all
# containers for MD superblocks. alternatively, specify devices to scan, using
# wildcards if desired.

The flash drive had only 2 partitions and the scan probably happened so fast I did not notice the 2 "mdadm: No array found in config file or automatically" lines. Now that it is on my hard disk it is scanning all 20 of its partitions. So, this would not be a problem on a drive with a more reasonable number of partitions. Also, apparently you can override the default and specify the partitions to scan. So, that may be a way to avoid all these scans. Don't know how to do that yet but will investigate further.

ADDENDUM:

I edited the file /etc/mdadm/mdadm.conf by adding the line:

DEVICE /dev/sdb20

That should limit the scanning to only my root partition. Since the initrd file has a copy of mdadm.conf I ran the command:

sudo update-initramfs -u

This will regenerate the latest /boot/initrd.img-5.10.*-*-686-pae. I would make a backup of this file first. In my case update-initramfs displayed errors and warnings but the computer still booted and scanned only 1 partition instead of 20.

Last edited by magenta-cuda (2022-01-14 23:02)