Re: [Devil-linux-develop] 1.3.5 Query

[Bruce S. <bw...@ar...>]

> > The mount goes like this (as I recall from memory):
> > mount -t aufs -o dirs=/shm/etc-mods:/etc-cd=ro none /shm/etc
> > 
> > Make sense?
> 
> I thought yesterday you'd done something differently.  Basically I 
> didn't understand - still don't actually.
> 
> If you look in mtab  the mount looks quite different. In particualer 
> /etc-cd is mounted rr (really readonly).  Is this significant?  Probably 
> not.  

I typed the mount yesterday from memory.  A copy/paste of the actual
mount being used is:

  mount -n -t aufs -o br:/shm/etc-mods:/etc-cd=rr none /shm/etc

I tried "rr" and "ro" for /etc-cd without any difference.  The docs say
that "rr" is faster for volumes that cannot physically be written to,
like a CD or ISO9660, so I settled on "rr".

Keep in mind, that "mount.aufs" is a shell script, that tweaks the
command line options, which is why /proc/mounts & mtab is different.

FYI, when running UnionFS, the equivalent mount statement used was:

  mount -n -t unionfs -o dirs=/shm/etc-mods:/etc-cd=ro none /shm/etc

> But it is like the whole of /etc-cd is being written into 
> etc-mods.  It's baffling.

It's not the whole thing.  On a DL Apache / PHP / MySQL / firewall I'm
running, the size difference between the saved configs is significant:

-rwxr-xr-x 1 root root  230221 Apr 16 16:12 etc-mods.tar.bz2
-rwxr-xr-x 1 root root 1114236 Apr 16 19:21 etc.tar.bz2

After sleeping on it, I have another theory.  Which may or may not go
anywhere.  I'll let you know if I find anything!  :-)

 - BS