In message <[EMAIL PROTECTED]>, "Stan Franker jr" writes:

> when issueing the command: mount -t unionfs -o 
> dirs=/mnt/disk1=ro:/mnt/disk2=ro unionfs /ftp/site/archive
> 
> i get:
> 
> mount: wrong fs type, bad option, bad superblock on unionfs-mv,
>        missing codepage or other error
>        In some cases useful info is found in syslog - try
>        dmesg | tail  or so
> 
> dmesg output is:
> 
> NET: Registered protocol family 10
> lo: Disabled Privacy Extensions
> IPv6 over IPv4 tunneling driver
> eth0: no IPv6 routers present
> Installing knfsd (copyright (C) 1996 [EMAIL PROTECTED]).
> NFSD: Using /var/lib/nfs/v4recovery as the NFSv4 state recovery directory
> NFSD: starting 90-second grace period
> unionfs_read_super: error while parsing options (err = -22)
> unionfs_read_super: error while parsing options (err = -22)
> unionfs_read_super: error while parsing options (err = -22)
> 
> i'm using
> 
> Linux debian 2.6.18-4-686 #1 SMP Mon Mar 26 17:17:36 UTC 2007 i686 GNU/Linux
> 
> with unionfs-1.4. Is this a compatibility issue? According to
> http://www.am-utils.org/project-unionfs.html unionfs-1.4 is compatible
> with kernel 2.6.18.8 which is obviously newer then what i am using.
> 
> regards,
> 
> Stan

Stan, it looks like you're trying to produce a real-only union, because all
your branches are marked as readonly.  In unionfs, if you want a readonly
union, you must pass the "-o ro" option to /sbin/mount; otherwise, you can't
have the leftmost branch be readonly (unionfs needs a writable branch to
copyup to).

Unfortunately, unionfs 1.x doesn't give you a good message saying this.  In
unionfs 2.0, we fixed it so that at least the kernel message you get will
tell you how to produce a readonly union the right way.

In case you're wondering why can't we just detect that the leftmost branch
is set to "=ro" and treat the whole union as a readonly union -- we can't.
The kernel and esp. the VFS do certain special things only when a user
passes "-o ro" to the mount(2) syscall; by the time a file system like
unionfs detects that a leftmost branch has been set to readonly, it's too
late to muck with the VFS's own state.

BTW. if you're using 2.6.18, I'd recommend you use our latest unionfs 2.0
backport which we made recently.  Unionfs 2.0 is much more stable and
functional than 1.x.  If you do move up to 2.0, we'd love to hear some
feedback from you on how it works for you.

Cheers,
Erez.
_______________________________________________
unionfs mailing list: http://unionfs.filesystems.org/
[email protected]
http://www.fsl.cs.sunysb.edu/mailman/listinfo/unionfs

Reply via email to