the 'why' of pseudofs

[Bill Hacker]

Jost Tobias Springenberg wrote:
I do not want to sound offensive here but I don't get the point of this discussion at all.
What exactly is wrong with null mounts and / or the way PFS work ?
If you want to have seperate partitions instead of PFS, thats perfectly fine, nobody 
forces you to use PFS everywhere. In fact It might be very reasonable to keep data from home 
directories seperated from other data or the like.

Regarding null_mounts, I do not see any programm that might not be able to work with them.
And User failure is also not a real issue here, as those mounts can be secified in fstab as well as 
any other mount and the concept is not that hard to grasp.
Regards,
	Tobi
No offense taken (nor meant).

And thanks for the input - taken on-board.

For someone who has spent much of the last two years experimenting with 
Gfarm, Gluster, Ceph, DFarm, Chiron, AFS, Coda, (AND NOT ZFS) etc ad 
nauseum..

. .even (most reluctantly) having to endure Linux lib-version-Hell to be 
able to test several of those too-often 'fuse' dependent critters *at all*,

. . it isn't the *concept* that is hard to grasp.

It's the "gotcha's" I'm trying to ring-fence.

;-)

And, to seek better sync between docs and methods.

EX:

man (5) hammer has an example of creating and mounting /home/pfs/master, 
/home/pfs/slave. Then /home/master and 'home/slave for mirror-copy >> 
mirror-stream.

But the 2.3.0 DEVELOPMENT iso had already mounted /home (/usr, /var, 
etc) .... as PFS....

By the time I had sorted a new non-pfs mount directly off '/' and got 
all the mirror-stream stuff working, a simple reboot blew way the 
now-multiply-recursively-mounted, BFBI privs and ownership FUBAER'ed, 
and overly aggressive pfs-destroy'ed,  '/home' altogether

. .. *before* I had remapped all console messages to a log file.. so I 
saw it complain - but had no details.

Recoverable? Maybe, maybe not.

But testing calls for a complete re-install to a different formula 
anyway, so....

'Essayons'

Regards,

Bill