Initial provisioner configuration
Features all the components of creating various templates and scripts for the provisioner, as well as VM profiles combining these.
This commit is contained in:
168
client-provisioner/examples/provisioning_script.py
Normal file
168
client-provisioner/examples/provisioning_script.py
Normal file
@ -0,0 +1,168 @@
|
||||
#!/usr/bin/env python3
|
||||
|
||||
# provisioing_script.py - PVC Provisioner example script
|
||||
# Part of the Parallel Virtual Cluster (PVC) system
|
||||
#
|
||||
# Copyright (C) 2018-2019 Joshua M. Boniface <joshua@boniface.me>
|
||||
#
|
||||
# This program is free software: you can redistribute it and/or modify
|
||||
# it under the terms of the GNU General Public License as published by
|
||||
# the Free Software Foundation, either version 3 of the License, or
|
||||
# (at your option) any later version.
|
||||
#
|
||||
# This program is distributed in the hope that it will be useful,
|
||||
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
# GNU General Public License for more details.
|
||||
#
|
||||
# You should have received a copy of the GNU General Public License
|
||||
# along with this program. If not, see <https://www.gnu.org/licenses/>.
|
||||
#
|
||||
###############################################################################
|
||||
|
||||
# This script provides an example of a PVC provisioner script. It will install
|
||||
# a Debian system, of the release specified in the keyword argument `deb_release`
|
||||
# and from the mirror specified in the keyword argument `deb_mirror`, and
|
||||
# including the packages specified in the keyword argument `deb_packages` (a list
|
||||
# of strings, which is then joined together as a CSV and passed to debootstrap),
|
||||
# to the configured disks, configure fstab, and install GRUB. Any later config
|
||||
# should be done within the VM, for instance via cloud-init.
|
||||
|
||||
# This script can thus be used as an example or reference implementation of a
|
||||
# PVC provisioner script and expanded upon as required.
|
||||
|
||||
# This script will run under root privileges as the provisioner does. Be careful
|
||||
# with that.
|
||||
|
||||
import os
|
||||
|
||||
# Installation function - performs a debootstrap install of a Debian system
|
||||
# Note that the only arguments are keyword arguments.
|
||||
def install(**kwargs):
|
||||
# The provisioner has already mounted the disks on kwargs['temporary_directory'].
|
||||
# by this point, so we can get right to running the debootstrap after setting
|
||||
# some nicer variable names; you don't necessarily have to do this.
|
||||
vm_name = kwargs['vm_name']
|
||||
vm_id = kwargs['vm_id']
|
||||
temporary_directory = kwargs['temporary_directory']
|
||||
disks = kwargs['disks']
|
||||
networks = kwargs['networks']
|
||||
# Our own required arguments. We should, though are not required to, handle
|
||||
# failures of these gracefully, should administrators forget to specify them.
|
||||
try:
|
||||
deb_release = kwargs['deb_release']
|
||||
except:
|
||||
deb_release = "stable"
|
||||
try:
|
||||
deb_mirror = kwargs['deb_mirror']
|
||||
except:
|
||||
deb_mirror = "http://ftp.debian.org/debian"
|
||||
try:
|
||||
deb_packages = kwargs['deb_packages']
|
||||
except:
|
||||
deb_packages = ["linux-image-amd64", "grub-pc", "cloud-init", "python3-cffi-backend"]
|
||||
|
||||
# We need to know our root disk
|
||||
root_disk = None
|
||||
for disk in disks:
|
||||
if disk['mountpoint'] == '/':
|
||||
root_disk = disk
|
||||
if not root_disk:
|
||||
return
|
||||
print(root_disk)
|
||||
|
||||
# Ensure we have debootstrap intalled on the provisioner system; this is a
|
||||
# good idea to include if you plan to use anything that is not part of the
|
||||
# base Debian host system, just in case the provisioner host is not properly
|
||||
# configured already.
|
||||
os.system(
|
||||
"apt-get install -y debootstrap"
|
||||
)
|
||||
|
||||
# Perform a deboostrap installation
|
||||
os.system(
|
||||
"debootstrap --include={pkgs} {suite} {target} {mirror}".format(
|
||||
suite=deb_release,
|
||||
target=temporary_directory,
|
||||
mirror=deb_mirror,
|
||||
pkgs=','.join(deb_packages)
|
||||
)
|
||||
)
|
||||
|
||||
# Bind mount the devfs
|
||||
os.system(
|
||||
"mount --bind /dev {}/dev".format(
|
||||
temporary_directory
|
||||
)
|
||||
)
|
||||
|
||||
# Create an fstab entry for each disk
|
||||
fstab_file = "{}/etc/fstab".format(temporary_directory)
|
||||
for disk in disks:
|
||||
# We assume SSD-based/-like storage, and dislike atimes
|
||||
options = "defaults,discard,noatime,nodiratime"
|
||||
|
||||
# The root and var volumes have specific values
|
||||
if disk['mountpoint'] == "/":
|
||||
dump = 0
|
||||
cpass = 1
|
||||
elif disk['mountpoint'] == '/var':
|
||||
dump = 0
|
||||
cpass = 2
|
||||
else:
|
||||
dump = 0
|
||||
cpass = 0
|
||||
|
||||
# Append the fstab line
|
||||
with open(fstab_file, 'a') as fh:
|
||||
fh.write("/dev/{disk} {mountpoint} {filesystem} {options} {dump} {cpass}\n".format(
|
||||
disk=disk['name'],
|
||||
mountpoint=disk['mountpoint'],
|
||||
filesystem=disk['filesystem'],
|
||||
options=options,
|
||||
dump=dump,
|
||||
cpass=cpass
|
||||
))
|
||||
|
||||
# Write the GRUB configuration
|
||||
grubcfg_file = "{}/etc/default/grub".format(temporary_directory)
|
||||
with open(grubcfg_file, 'w') as fh:
|
||||
fh.write("""# Written by the PVC provisioner
|
||||
GRUB_DEFAULT=0
|
||||
GRUB_TIMEOUT=1
|
||||
GRUB_DISTRIBUTOR="PVC Virtual Machine"
|
||||
GRUB_CMDLINE_LINUX_DEFAULT="root=/dev/{root_disk} console=tty0 console=ttyS0,115200n8"
|
||||
GRUB_CMDLINE_LINUX=""
|
||||
GRUB_TERMINAL=console
|
||||
GRUB_SERIAL_COMMAND="serial --speed=115200 --unit=0 --word=8 --parity=no --stop=1"
|
||||
GRUB_DISABLE_LINUX_UUID=false
|
||||
""".format(root_disk=root_disk['name']))
|
||||
|
||||
# Chroot and install GRUB so we can boot, then exit the chroot
|
||||
# EXITING THE CHROOT IS VERY IMPORTANT OR THE FOLLOWING STAGES OF THE PROVISIONER
|
||||
# WILL FAIL IN UNEXPECTED WAYS! Keep this in mind when using chroot in your scripts.
|
||||
real_root = os.open("/", os.O_RDONLY)
|
||||
os.chroot(temporary_directory)
|
||||
fake_root = os.open("/", os.O_RDONLY)
|
||||
os.fchdir(fake_root)
|
||||
os.system(
|
||||
"grub-install /dev/rbd/{}".format(root_disk['volume'])
|
||||
)
|
||||
os.system(
|
||||
"update-grub"
|
||||
)
|
||||
# Restore our original root
|
||||
os.fchdir(real_root)
|
||||
os.chroot(".")
|
||||
os.fchdir(real_root)
|
||||
os.close(fake_root)
|
||||
os.close(real_root)
|
||||
|
||||
# Unmount the bound devfs
|
||||
os.system(
|
||||
"umount {}/dev".format(
|
||||
temporary_directory
|
||||
)
|
||||
)
|
||||
|
||||
# Everything else is done via cloud-init
|
||||
Reference in New Issue
Block a user