| Subject: ANNOUNCE: mdadm 3.3.4 - A tool for managing md Soft RAID under Linux |
| |
| I am somewhat disappointed to have to announce the availability of |
| mdadm version 3.3.4 |
| |
| It is available at the usual places: |
| http://www.kernel.org/pub/linux/utils/raid/mdadm/ |
| and via git at |
| git://github.com/neilbrown/mdadm |
| git://neil.brown.name/mdadm |
| http://git.neil.brown.name/git/mdadm.git |
| |
| In mdadm-3.3 a change was made to how IMSM (Intel Matrix Storage |
| Manager) metadata was handled. Previously an IMSM array would only |
| be assembled if it was attached to an IMSM controller. |
| |
| In 3.3 this was relaxed as there are circumstances where the |
| controller is not properly detected. Unfortunately this has negative |
| consequences which have only just come to light. |
| |
| If you have an IMSM RAID1 configured and then disable RAID in the |
| BIOS, the metadata will remain on the devices. If you then install |
| some other OS on one device and then install Linux on the other, Linux |
| might eventually start noticing the IMSM metadata (depending a bit on whether |
| mdadm is included in the initramfs) and might start up the RAID1. This could |
| copy one device over the other, thus trashing one of the installations. |
| |
| Not good. |
| |
| So with this release IMSM arrays will only be assembled if attached to |
| an IMSM controller, or if "--force" is given to --assemble, or if the |
| environment variable IMSM_NO_PLATFORM is set (used primarily for |
| testing). |
| |
| I strongly recommend upgrading to 3.3.4 if you are using 3.3 or later. |
| |
| NeilBrown 3rd August 2015. |