mirror of https://github.com/vitalif/e2fsprogs
0f5eba7501
Multi-mount protection is feature that allows mke2fs, e2fsck, and others to detect if the filesystem is mounted on a remote node (on SAN disks) and avoid corrupting the filesystem. For e2fsprogs this means that it checks the MMP block to see if the filesystem is in use, and marks the filesystem busy while e2fsck is running on the system. This is useful on SAN disks that are shared between high-availability servers, or accessible by multiple nodes that aren't in HA pairs. MMP isn't intended to serve as a primary HA exclusion mechanism, but as a failsafe to protect against user, software, or hardware errors. There is no requirement that e2fsck updates the MMP block at regular intervals, but e2fsck does this occasionally to provide useful information to the sysadmin in case of a detected conflict. For the kernel (since Linux 3.0) MMP adds a "heartbeat" mechanism to periodically write to disk (every few seconds by default) to notify other nodes that the filesystem is still in use and unsafe to modify. Originally-by: Kalpak Shah <kalpak@clusterfs.com> Signed-off-by: Johann Lombardi <johann@whamcloud.com> Signed-off-by: Andreas Dilger <adilger@whamcloud.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> |
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| .. | ||
| Makefile.in | ||
| e2p.h | ||
| e2p.pc.in | ||
| feature.c | ||
| fgetflags.c | ||
| fgetversion.c | ||
| fsetflags.c | ||
| fsetversion.c | ||
| getflags.c | ||
| getversion.c | ||
| hashstr.c | ||
| iod.c | ||
| ls.c | ||
| mntopts.c | ||
| ostype.c | ||
| parse_num.c | ||
| pe.c | ||
| percent.c | ||
| pf.c | ||
| ps.c | ||
| setflags.c | ||
| setversion.c | ||
| uuid.c | ||