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diff --git a/ANNOUNCE-3.0-devel3 b/ANNOUNCE-3.0-devel3 deleted file mode 100644 index 078be07..0000000 --- a/ANNOUNCE-3.0-devel3 +++ /dev/null @@ -1,113 +0,0 @@ -Subject: ANNOUNCE: mdadm 3.0-devel3 - A tool for managing Soft RAID under Linux - -I am pleased to announce the availability of - mdadm version 3.0-devel3 - -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 should be used with -caution, though it is believed to be close to release-candidate stage. - -There have been numerous improvements and additions since -devel2. -I think we are close to a release of 3.0. - -I need to add lots of tests to the test suite to test the new -functionality. And I need to review the man pages. - -After that I will release -rc1 followed by -final. - - -The following is the same introduction to 3.x as appeared in -previous announcements. - - -Any testing and feedback will be greatly appreciated. - -NeilBrown 10th March 2009 - - -===================================================== - -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. - -Also the approach to device names has changed significantly. - -If udev is installed on the system, mdadm will not create any devices -in /dev. Rather it allows udev to manage those devices. For this to work -as expected, the included udev rules file should be installed. - -If udev is not install, mdadm will still create devices and symlinks -as required, and will also remove them when the array is stopped. - -mdadm now requires all devices which do not have a standard name (mdX -or md_dX) to live in the directory /dev/md/. Names in this directory -will always be created as symlinks back to the standard name in /dev. - -The man pages contain some information about the new externally managed -metadata. However see below for a more condensed overview. - -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] - -To 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. |