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diff --git a/ANNOUNCE-3.0-devel1 b/ANNOUNCE-3.0-devel1 deleted file mode 100644 index 89ed2e3..0000000 --- a/ANNOUNCE-3.0-devel1 +++ /dev/null @@ -1,84 +0,0 @@ -Subject: ANNOUNCE: mdadm 3.0-devel1 - A tool for managing Soft RAID under Linux - -I am pleased to announce the availability of - mdadm version 3.0-devel1 - -It is available at the usual places: - countrycode=xx. - http://www.${countrycode}kernel.org/pub/linux/utils/raid/mdadm/ -and via git at - git://neil.brown.name/mdadm - http://neil.brown.name/git?p=mdadm - -Note that this is a "devel" release. It is not intended for -production use yet, but rather for testing and ongoing development. - -The significant change which justifies the new major version number is -that mdadm can now handle metadata updates entirely in userspace. -This allows mdadm to support metadata formats that the kernel knows -nothing about. - -Currently two such metadata formats are supported: - - DDF - The SNIA standard format - - Intel Matrix - The metadata used by recent Intel ICH controlers. - -The manual pages have not yet been updated, but here is a brief outline. - -Externally managed metadata introduces the concept of a 'container'. -A container is a collection of (normally) physical devices which have -a common set of metadata. A container is assembled as an md array, but -is left 'inactive'. - -A container can contain one or more data arrays. These are composed from -slices (partitions?) of various devices in the container. - -For example, a 5 devices DDF set can container a RAID1 using the first -half of two devices, a RAID0 using the first half of the remain 3 devices, -and a RAID5 over thte second half of all 5 devices. - -A container can be created with - - mdadm --create /dev/md0 -e ddf -n5 /dev/sd[abcde] - -or "-e imsm" to use the Intel Matrix Storage Manager. - -An array can be created within a container either by giving the -container name and the only member: - - mdadm -C /dev/md1 --level raid1 -n 2 /dev/md0 - -or by listing the component devices - - mdadm -C /dev/md2 --level raid0 -n 3 /dev/sd[cde] - -The assemble a container, it is easiest just to pass each device in turn to -mdadm -I - - for i in /dev/sd[abcde] - do mdadm -I $i - done - -This will assemble the container and the components. - -Alternately the container can be assembled explicitly - - mdadm -A /dev/md0 /dev/sd[abcde] - -Then the components can all be assembled with - - mdadm -I /dev/md0 - -For each container, mdadm will start a program called "mdmon" which will -monitor the array and effect any metadata updates needed. The array is -initially assembled readonly. It is up to "mdmon" to mark the metadata -as 'dirty' and which the array to 'read-write'. - -The version 0.90 and 1.x metadata formats supported by previous -versions for mdadm are still supported and the kernel still performs -the same updates it use to. The new 'mdmon' approach is only used for -newly introduced metadata types. - -Any testing and feedback will be greatly appreciated. - -NeilBrown 18th September 2008 - |