[lxc-devel] pin root fs patch

[Serge Hallyn]

Hi Guido,

the ideas are interesting, and the fifo might be a nice feature to add
separately if someone wanted to work on the patch.  However, in my view
this particular patch is an ugly hack to work around an ugly kernel
deficiency which hopefully will be fixed in the kernel (when I get
around to it, probably).  So I wouldn't want to cobble the configuration
file API for it.  I don't care what the hold file is actually called,
however I went for a shorter name to try and avoid having the filename
be > MAXPATHLENGTH and now have container creation fail for that :)
Maybe just '.pin'?

Daniel,

this patch isn't in my github tree yet.  I will be pushing several
patches as soon as our freeze is over (and I'm sure I'm making no
more changes)

thanks,
-serge

Quoting Jäkel, Guido (G.Jaekel at dnb.de):
> Dear Serge,
> 
> thank you for pushing this patch. My five cents on it:
> 
> * I ever attempt to use "just one name for it"; therefore I would suggest to call the file ".pin_rootfs".
> * Maybe this should be configurable (label lxc.rootfs.pinfile ?), with the above as a default.
> * Maybe it should be switchable. If it is configurable as above, maybe choosing a empty value will disable it.
> 
> 
> As an outlook for further development, the file might be filled with some "usefull information"(tm); what's about the hostname of the host as a reference information for the container? But maybe this should be realized as a procfs extension inside the container. 
> 
> Or act as a FIFO between the host and the container to attach a small userland command daemon inside the container to it -- to my knowledge Ulrich Horlacher uses such.
> 
> Guido