[linux-fai] add packages to /usr/lib/fai/nfsroot

[Thomas Gebhardt]

Hi,

there has been a thread "Initiales Booten und /usr per NFS" on this
list discussing whether or not it makes sense to mount /usr on a
fai client or to install additional packages on the fai nfsroot
root partition.

Thomas Lange wrote:

> erzeuge ein sources.list in /usr/lib/fai/nfsroot
> cp sources.list /usr/lib/fai/nfsroot/etc/apt
> chroot /usr/lib/fai/nfsroot apt-get update
> chroot /usr/lib/fai/nfsroot apt-get install rdate cfengine ....
> 
> das muesste dann in das postinst Skript rein. Kling jetzt einfach, werde ich
> aber erst im Juni testen. Ich habe auch schon daran gedacht ein

Since I prefer not to mount /usr from the server I tried to write
a script that does exactly this,

1. Copies apt sources list
2. Updates packages on nfsroot
3. Reads two lists of packages from /etc/fai/nfsroot-packages.dist
   and /etc/fai/nfsroot-packages.local
   (the packages from the *.dist configuration file are considered
   to be needed for fai, the packages in *.local are my personal
   add-ons. BTW: I really enjoy using FAI as a "rescue disk" providing
   a root shell in case of emergency)
4. Installs additional packages

Here is /etc/fai/nfsroot-packages.dist:

# Packages added to fai nfsroot
kernel-image-2.2.15
perl-5.005
cfengine
rsh-client
wget
bootpc
file
rdate
ntpdate

/etc/fai/nfsroot-packages.local:

# Packages added to fai nfsroot (local add-ons)
emacs20
ssh
lvm
less
raidtools2

and, finally, the script:

#!/usr/bin/perl

$dist_packages_file = "/etc/fai/nfsroot-packages.dist";
$local_packages_file = "/etc/fai/nfsroot-packages.local";

$fai_client_root = "/usr/lib/fai/nfsroot";

# don't start daemons when installing packages on nfsroot image
system ("ln -sf ${fai_client_root}/bin/true ../../tmp/start-stop-daemon");
$ENV{PATH} = "/tmp:" . $ENV{PATH};

print "copying apt configuration files form /etc/apt/ to";
print "  $fai_client_root/etc/apt/  ...\n";
system("cp /etc/apt/* $fai_client_root/etc/apt");

print "copying /etc/resolv.conf to $fai_client_root/tmp/etc/  ...\n";
system("mkdir -p $fai_client_root/tmp/etc");
system("cp -f /etc/resolv.conf $fai_client_root/tmp/etc/resolv.conf");

# some packages need /proc mounted during installation:
system("mount -t proc proc $fai_client_root/proc/ ");

# dummy fstab needed to make lilo installation script happy:
open (FSTAB, ">$fai_client_root/etc/fstab");
print FSTAB <<EOF;
# /etc/fstab: dummy file system information.
#
/dev/hda1       /               ext2    defaults,errors=remount-ro   0      1
EOF
close (FSTAB);

print "updating database of available packages ...\n";
system("chroot $fai_client_root apt-get update");

print "upgrading packages to current version ...\n";
system("chroot $fai_client_root apt-get -f upgrade");
# need this if dependencies are broken:
system("chroot $fai_client_root apt-get -f install"); 

if (-r $dist_packages_file) {
    open (DISTPACKAGES, $dist_packages_file) or warn
          "cannot open $dist_packages_file for reading";
    print "installing packages in $dist_packages_file ...\n";
    while (<DISTPACKAGES>) {
	chomp;
	s/#.*//;  # deleting comments
	s/\s//g;  # deleting whitespace
	if (/^(\S+)$/) {
            print "instaling packages $1 ...\n";
	    system ("chroot $fai_client_root apt-get -f install $1");
	}
    }
    close(DISTPACKAGES);
}

if (-r $local_packages_file) {
    open (LOCALPACKAGES, $local_packages_file) or warn
          "cannot open $local_packages_file for reading";
    print "installing packages in $local_packages_file ...\n";
    while (<LOCALPACKAGES>) {
	chomp;
	s/#.*//;  # deleting comments
	s/\s//g;  # deleting whitespace
	if (/^(\S+)$/) {
            print "instaling packages $1 ...\n";
	    system ("chroot $fai_client_root apt-get -f install $1");
	}
    }
    close(LOCALPACKAGES);
}

system("umount $fai_client_root/proc/ ");

# cfengine need /var/run/ writable
system ("chroot $fai_client_root rm -rf /var/run");
system ("chroot $fai_client_root ln -s /tmp/var/run var/run");

# ssh needs .ssh writable
system ("chroot $fai_client_root rm -rf .ssh");
system ("chroot $fai_client_root ln -s /tmp/.ssh .ssh");

--------------------------------------------------------

This script is not intended to work without user interaction,
you have to type "return" several times. Up to now there is one
additional glitch: the lilo installation script expects to
find a kernel image "/vmlinuz". I don't yet have an idea how
to handle this gracefully. I just manually set a symbolic link
from /vmlinuz to the kernel image in /boot in the nfsroot
filesystem when running the script ("fai_add_packages") the first
time.

Kind regards, Thomas