Re: [coLinux-users] unionfs in colinux?

[Henry N. <Hen...@Ar...>]

David Kaufman wrote:
> Hi,
> 
> I'd like to use unionfs in colinux:
> http://www.fsl.cs.sunysb.edu/project-unionfs.html
> 
> My goal is to have several colinux instances sharing a large read-only 
> filesystem (like the OS images that ship with colinux) and saving their 
> local changes to smaller writable local "unioned" filesystems.  This would 
> help me to repeatedly test-install large, complicated software packages 
> that we develop (such as http://krang.sf.net), with the ability to quickly 
> roll back the O/S to its pristine state and re-do as many times as needed, 
> and also to make it easy to identify and isolate all changes made to the 
> underlying distro afterwards (by examining the writable directory mounted).
> 
> I read that unionfs was "baked in" to the linux kernel since 2.6.14 and 
> also see that it is supported by my distro (debian etch) so I was 
> disappointed when:
> 
>   mount -t unionfs -o dirs=/Fruits:/Vegetables none /mnt/healthy
> 
> complained that:
> 
>   unknown file system unionfs
> 
> Is unionfs not baked into the colinux kernel, too?  Am I doing something 
> wrong (or not doing something else right?)  Do I need to get the source, 
> compile and load the kernel module for colinux?  I've never done that 
> before, but for this I'd be anxious to give it a try!
> 
> I'm running a recent 0.8.0 snapshot (at the moment) but would be willing to 
> up-, down-, or side-grade to get unionfs running!

Unionfs is not in the vanilla kernel. I have grepped the conmplete tree
for "unionfs". Only found one comemnt, but no code.

You needs to have a kernel 2.6.22(.19) patch from unionfs team [1] and
must patch this over the colinux patched kernel. Than needs to
reconfigure the kernel and test it. Please read the doc/building or [2],
section "4. Building a coLinux kernel".

We have kernel 2.6.22.18, but see, there are no conflicts in patch for
2.6.22.19, think is usable.

[1] http://www.fsl.cs.sunysb.edu/project-unionfs.html
[2] http://colinux.wikia.com/wiki/BuildingColinux0.8.0

-- 
Henry N.