Hello Achim,
Achim Scheidl:
> # sudo mount -t aufs -o br:./project=ro:./platform=ro none ./deployment
:::
> # echo platform-content > platform/b
> # echo proj-content > project/b
> # cat deployment/b
> platform-content
> ^---- that is suspicious for me, I modified the file "b" in platform
> directory first, so project changes are ignored???
Ok, you are modifying files on branch-fs directly.
> # sudo mount -o remount ./deployment
> # cat deployment/b
> proj-content
> ^--- now it's fine again, the remount brought back expected behavior
Yes, remounting causes discarding caches (which are not in use).
And you can see latest file-data.
> Do I really need to do a remount every time I update some files to make
> sure the expected content is visible in the union directory?
> Are there some more parameters needed during mount to make the updates
> appearing in union??
> (I already played with "udba=notify," bit it only claims about "bad option")
The mount option "udba=notify" is exactly just for users like you who
modifies branch fs directly.
The error "bad option" means you didn't enable CONFIG_AUFS_HNOTIFY.
(from fs/aufs/Kconfig)
----------------------------------------------------------------------
config AUFS_HNOTIFY
bool "Detect direct branch access (bypassing aufs)"
help
If you want to modify files on branches directly, eg. bypassing aufs,
and want aufs to detect the changes of them fully, then enable this
option and use 'udba=notify' mount option.
Currently there is only one available configuration, "fsnotify".
It will have a negative impact to the performance.
See detail in aufs.5.
----------------------------------------------------------------------
Try enabling CONFIG_AUFS_HNOTIFY, re-build your kernel, and you will see
latest file-data via deployment/b.
J. R. Okajima
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