Add PNIN as a system manifest parameter.

Fixes: andsens#349

Adds a new boolean parameter indicating weather to use PNIN or not to
the system section of the manifest.

The default, False enables tasks for extlinux and grub to pass
net.ifnames=0 biosdevnames=0 parameters to the kernel.

Previously for grub PNIN was disabled for stretch and later. This
remains the default but setting system.pnin True will allow the behavior
to be overridden. The additional parameters have no effect on earlier
releases are passed regardless. Extlinux had no prior special behavior,
it now mirrors grub.

bootstrapvz/base/manifest-schema.yml

@@ -59,6 +59,7 @@ properties:
         type: string
         pattern: ^\S+$
       locale: {type: string}
+      pnin: {type: boolean}
       release: {type: string}
       timezone: {type: string}
     required:

bootstrapvz/common/assets/extlinux/extlinux.conf

@@ -10,12 +10,12 @@ timeout 50
 label l0
 	menu label Debian GNU/Linux, kernel {kernel_version}
 	linux {boot_prefix}/vmlinuz-{kernel_version}
-	append initrd={boot_prefix}/initrd.img-{kernel_version} root=UUID={root_uuid} ro quiet console=ttyS0
+	append initrd={boot_prefix}/initrd.img-{kernel_version} root=UUID={root_uuid} ro quiet console=ttyS0 {disable_pnin}
 
 label l0r
 	menu label Debian GNU/Linux, kernel {kernel_version} (recovery mode)
 	linux {boot_prefix}/vmlinuz-{kernel_version}
-	append initrd={boot_prefix}/initrd.img-{kernel_version} root=UUID={root_uuid} ro console=ttyS0 single
+	append initrd={boot_prefix}/initrd.img-{kernel_version} root=UUID={root_uuid} ro console=ttyS0 single {disable_pnin}
 	text help
    This option boots the system into recovery mode (single-user)
 	endtext

bootstrapvz/common/task_groups.py

@@ -161,6 +161,7 @@ def get_bootloader_group(manifest):
     from bootstrapvz.common.releases import jessie
     from bootstrapvz.common.releases import stretch
     group = []
+    pnin = manifest.system.get('pnin', None)
     if manifest.system['bootloader'] == 'grub':
         group.extend([grub.AddGrubPackage,
                       grub.InitGrubConfig,
@@ -173,7 +174,7 @@ def get_bootloader_group(manifest):
             group.append(grub.InstallGrub_1_99)
         else:
             group.append(grub.InstallGrub_2)
-        if manifest.release >= stretch:
+        if pnin is False or (pnin is None and manifest.release >= stretch):
             group.append(grub.DisablePNIN)
     if manifest.system['bootloader'] == 'extlinux':
         group.append(extlinux.AddExtlinuxPackage)

bootstrapvz/common/tasks/extlinux.py

@@ -4,6 +4,7 @@
 from . import filesystem
 from . import kernel
 from bootstrapvz.base.fs import partitionmaps
+from ..releases import stretch
 import os
 
 
@@ -75,6 +76,12 @@ def run(cls, info):
         else:
             config_vars['boot_prefix'] = '/boot'
 
+        pnin = info.manifest.system.get('pnin', None)
+        if pnin is False or (pnin is None and info.manifest.release >= stretch):
+            config_vars['disable_pnin'] = 'net.ifnames=0 biosdevname=0'
+        else:
+            config_vars['disable_pnin'] = ''
+
         extlinux_config = extlinux_config_tpl.format(**config_vars)
 
         with open(os.path.join(extlinux_path, 'extlinux.conf'), 'w') as extlinux_conf_handle:

manifests/README.rst

@@ -162,6 +162,11 @@ system and does not fit under any other section.
 -  ``locale``: The default locale of the system.
    Valid values: Any locale mentioned in ``/etc/locale.gen``
    ``required``
+-  ``pnin``: Enable Persistent Network Interface Naming in the bootloader.
+   Only supported with the ``grub`` and ``extlinux`` bootloaders.
+   Valid values: ``true``, ``false``
+   Default: ``false``
+   ``optional``
 -  ``release``: Defines which debian release should be bootstrapped.
    Valid values: ``wheezy``, ``jessie``, ``stretch``, ``sid``,
    ``oldstable``, ``stable``, ``testing``, ``unstable``