When creating a raid 1 array in ubuntu using mdadm

mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sdb /dev/sdc

after formatting

 mkfs.ext4 /dev/md0

and mount

 mount /dev/md0 /mnt/newraid

Long synchronization of disks began, 2 disks on 6Tb

 echo 999999 > /proc/sys/dev/raid/speed_limit_min

The disks are completely empty, can I somehow cancel or speed up synchronization?

  • Created the 5th of 3 screws of 4TB each. Also empty. After creation - there was a degrading array with reassembly on the 3rd. I don’t know why this is so, but when I reconsider, the flight is quite normal for a couple of days. - don Rumata
  • this is normal. “Speeding up or canceling” is simply nothing . @donRumata, there is written about raid5. - aleksandr barakin
  • @alexanderbarakin, pasib, read. - don Rumata

1 answer 1

as written in the documentation , this is an absolutely normal initial synchronization process.

it pauses to perform I / O operations, and therefore creates the most minimal interference to the "normal" use of the array.

to cancel the initial synchronization (using the --assume-clean option) makes sense only in two cases:

  1. if the array already existed on these carriers and was only reassembled after reconnecting the disks, and you are absolutely sure that the information in the array is complete;
  2. if you build an array for some tests and the integrity of the information placed there is not important to you.

in one phrase: let the process go, it does not bother you.