Re: [linux-lvm] LVM and RO device/partition(s)
Zdenek Kabelac <[email protected]>
| Newsgroups | dev.linux.lists.linux-lvm |
|---|---|
| Message-ID | <[email protected]> |
Dne 19. 03. 23 v 11:27 Pascal napsal(a): > hi, > > the bio_check_ro function of the blk-core.c source file of the Linux kernel > refers to LVM : > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/block/blk-core.c?h=v6.2.7#n500 <https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/block/blk-core.c?h=v6.2.7#n500> > > how does LVM currently behave when faced with a device marked as readonly ? > does it automatically switch itself in readonly mode? > > according to some tests carried out in a virtual machine, it seems that it > doesn't and that LVM modifies the disk/partition(s) even though they are all > readonly (chmod 444 && blockdev --setro). Hi There is no extra logic around RO devices in lvm2. When lvm2 succeeds opening device in write mode, it'll use it for writing. Also note - when you 'activate' a LV in read-write mode - someone opens such LV/device and you later on 'lvchange' such active LV to read-only mode - all writers will keep writing to such device. It's not quite clear which kind of problem you are actually hitting - so maybe adding some more descriptive environment + logs might give more info about your individual case. Note: root admin typically can overwrite any 'mild' protections... Regards Zdenek _______________________________________________ linux-lvm mailing list [email protected] https://listman.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/