Jonathan Earl Brassow 6d04311efa Add the ability to split an image from the mirror and track changes. ... ~> lvconvert --splitmirrors 1 --trackchanges vg/lv The '--trackchanges' option allows a user the ability to use an image of a RAID1 array for the purposes of temporary read-only access. The image can be merged back into the array at a later time and only the blocks that have changed in the array since the split will be resync'ed. This operation can be thought of as a partial split. The image is never completely extracted from the array, in that the array reserves the position the device occupied and tracks the differences between the array and the split image via a bitmap. The image itself is rendered read-only and the name (<LV>_rimage_*) cannot be changed. The user can complete the split (permanently splitting the image from the array) by re-issuing the 'lvconvert' command without the '--trackchanges' argument and specifying the '--name' argument. ~> lvconvert --splitmirrors 1 --name my_split vg/lv Merging the tracked image back into the array is done with the '--merge' option (included in a follow-on patch). ~> lvconvert --merge vg/lv_rimage_<n> The internal mechanics of this are relatively simple. The 'raid' device- mapper target allows for the specification of an empty slot in an array via '- -'. This is what will be used if a partial activation of an array is ever required. (It would also be possible to use 'error' targets in place of the '- -'.) If a RAID image is found to be both read-only and visible, then it is considered separate from the array and '- -' is used to hold it's position in the array. So, all that needs to be done to temporarily split an image from the array /and/ cause the kernel target's bitmap to track (aka "mark") changes made is to make the specified image visible and read-only. To merge the device back into the array, the image needs to be returned to the read/write state of the top-level LV and made invisible.		2011-08-18 19:38:26 +00:00
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activate	Add the ability to split an image from the mirror and track changes.	2011-08-18 19:38:26 +00:00
cache	Add detect_internal_vg_cache_corruption to lvm.conf	2011-08-11 17:46:13 +00:00
commands	Add detect_internal_vg_cache_corruption to lvm.conf	2011-08-11 17:46:13 +00:00
config	Add detect_internal_vg_cache_corruption to lvm.conf	2011-08-11 17:46:13 +00:00
datastruct	Revert the #include changes. Need to fix this at the #include site for now, and	2011-07-18 14:34:33 +00:00
device	Fix warning for pvcreate over MD linear.	2011-07-08 15:53:59 +00:00
display	Fix some compile warnings on RHEL5	2011-03-01 20:17:56 +00:00
error	Add lv_activate_opts structure	2011-06-17 14:14:19 +00:00
filters	Add and use dev_open_readonly and variations.	2011-05-24 13:36:57 +00:00
format1	Defer writing PV labels to vg_write.	2011-06-01 19:29:31 +00:00
format_pool	Replace free_vg with release_vg	2011-08-10 20:25:29 +00:00
format_text	Replace free_vg with release_vg	2011-08-10 20:25:29 +00:00
freeseg	Replace malloc with zalloc when creating segment_type's	2011-03-25 21:59:42 +00:00
label	Report sector containing label in verbose message.	2011-06-01 15:30:36 +00:00
locking	Suppress locking error messages in monitoring init scripts.	2011-08-11 15:27:46 +00:00
log	Trivial, add void to ignore dm_snprinf result	2011-08-11 19:21:42 +00:00
metadata	Add the ability to split an image from the mirror and track changes.	2011-08-18 19:38:26 +00:00
mirror	Use lv_activate_opts struct instead of ACTIVATE_EXCL status flag.	2011-06-17 14:17:16 +00:00
misc	Add detect_internal_vg_cache_corruption to lvm.conf	2011-08-11 17:46:13 +00:00
mm	Maintain a count of the number of suspended devices in libdevmapper	2011-06-13 03:32:45 +00:00
raid	Compiler warning fixes, better error messaging, and cosmetic changes.	2011-08-13 04:28:34 +00:00
replicator	Add lv_activate_opts structure	2011-06-17 14:14:19 +00:00
report	Remove meaningless const type qualifiers on cast type	2011-08-04 14:30:51 +00:00
snapshot	Use lv_activate_opts struct instead of ACTIVATE_EXCL status flag	2011-06-17 14:22:48 +00:00
striped	Add lv_activate_opts structure	2011-06-17 14:14:19 +00:00
unknown	Slightly refactor the config code to allow better reuse (no functional change).	2011-07-18 13:26:08 +00:00
uuid	Revert the #include changes. Need to fix this at the #include site for now, and	2011-07-18 14:34:33 +00:00
zero	Add lv_activate_opts structure	2011-06-17 14:14:19 +00:00
Makefile.in	Add ability to down-convert RAID1 arrays.	2011-08-11 18:24:40 +00:00