Messages in this thread | | | Date | Wed, 03 Nov 2010 12:39:57 +0300 | From | Michael Tokarev <> | Subject | bind-mount vs second mount of the same blockdev? |
| |
Hello.
I'm trying to understand the differences between a bind-mount of a whole filesystem versus mounting the same block device the second time. Like this:
mount -t ext3 /dev/block /mnt/a mount --bind /mnt/a /mnt/b
versus
mount -t ext3 /dev/block /mnt/a mount -t ext3 /dev/block /mnt/b
In the second case, second mount does not happen but the first one is "reused" instead - this is visible in dmesg, since only once ext3fs prints a note about the mounting.
Now, the first case is quite clear: we've one fs visible in two places, pretty much like two hard- links to the same file. So things like, for example, fcntl locking will work "from" both ends. But it is not that obvious in the second case, even if we clearly have some common "inode" in this case too.
What are the differences in behavour?
Thanks!
/mjt
| |