From: Enrico Scholz (enrico.scholz_at_informatik.tu-chemnitz.de)
Date: Fri 10 Oct 2003 - 19:57:34 BST
jack_at_solucorp.qc.ca (Jacques Gelinas) writes:
> What is the current usage for namespace in the kernel. Is there other
> usage than pivot_root() ?
I am using it in my vrpm/vapt-get wrapper to
* use a custom /etc/rpm directory in the host
* make the rpmdb visible to the host-part of apt-get/rpm only (not the
%scriptlet, nor the other vserver-processes)
Basically, this happens by executing 'new-namespace vrpm-worker' and
vrpm-worker does
* mount --bind /vservers/.pkg/<foo>/rpm/etc /etc/rpm
* mount --bind /vservers/.pkg/<foo>/rpm/state /vservers/<foo>/.rpmdb
[Indeed, the second mount happens in a more secure way and the paths are
more general also]
The LD_PRELOAD wrapper for rpm's execv() creates a new namespace again,
umounts /.rpmdb and calls the %scriptlets.
The new-namespace utility is available in util-vserver CVS[1] and can be
executed e.g. as 'new-namespace /bin/sh'.
Enrico
Footnotes:
[1] http://savannah.nongnu.org/cgi-bin/viewcvs/util-vserver/util-vserver/src/new-namespace.c?rev=1.3&content-type=text/vnd.viewcvs-markup