Yes, copied from: pbuilder.
It is possible to use user-mode-linux by invoking pbuilder-user-mode-linux instead of pbuilder. pbuilder-user-mode-linux doesn't require root privileges, and it uses the copy-on-write (COW) disk access method of User-mode-linux which typically makes it much faster than the traditional pbuilder.
User-mode-linux is a somewhat less proven platform than the standard Unix tools which pbuilder relies on (chroot, tar, and gzip) but mature enough to support pbuilder-user-mode-linux since its version 0.59. And since then, pbuilder-user-mode-linux has seen a rapid evolution.
The configuration of pbuilder-user-mode-linux goes in three steps:
Configuration of user-mode-linux
user-mode-linux isn't completely trivial to set up. It would probably be useful to acquaint yourself with it a bit before attempting to use rootstrap or pbuilder-user-mode-linux. For details, read
/usr/share/doc/uml-utilities/README.Debian and the
user-mode-linux documentation. (It's in a separate package,
user-mode-linux requires the user to be in the uml-net group in order to configure the network unless you are using slirp.
If you compile your own kernel, you may want to verify that you enable TUN/TAP support, and you might want to consider the SKAS patch.
Configuration of rootstrap
rootstrap is a wrapper around debootstrap. It creates a Debian disk image for use with UML. To configure rootstrap, there are several requirements.
- Install the rootstrap package.
- TUN/TAP only: add the user to the uml-net group to allow access to the network
adduser dancer uml-net
- TUN/TAP only: Check that the kernel supports the TUN/TAP interface, or recompile the kernel if necessary.
/etc/rootstrap/rootstrap.conf. For example, if the current host is 192.168.1.2, changing following entries to something like this seems to work.
Some experimentation with configuration and running rootstrap ~/test.uml to actually test it would be handy.
Using slirp requires less configuration. The default configuration comes with a working example.
Configuration of pbuilder-uml
The following needs to happen:
- Install the
Set up the configuration file
/etc/pbuilder/pbuilder-uml.conf in the following manner. It will be different for slirp.
It needs to match the rootstrap configuration.
- Make sure BUILDPLACE is writable by the user. Change BUILDPLACE in the configuration file to a place where the user has access.
pbuilder-user-mode-linux create --distribution sid to create the image.
- Try running pbuilder-user-mode-linux build.
Extra comments in the link:
pbuilder-user-mode-linux emulates most of pbuilder, but there are some differences.
- pbuilder-user-mode-linux does not support all options of pbuilder properly yet. This is a problem, and will be addressed as specific areas are discovered.
- /tmp is handled differently inside pbuilder-user-mode-linux. In pbuilder-user-mode-linux, /tmp is mounted as tmpfs inside UML, so accessing files under /tmp from outside user-mode-linux does not work. It affects options like --configfile, and when trying to build packages placed under /tmp.
To run pbuilder-user-mode-linux in parallel on a system, there are a few things to bear in mind.
- The create and update methods must not be run when a build is in progress, or the COW file will be invalidated.
- If you are not using slirp, user-mode-linux processes which are running in parallel need to have different IP addresses. Just trying to run the pbuilder-user-mode-linux several times will result in failure to access the network. But something like the following will work: