container: T578: backport podman from 1.4 development branch

1 files changed, 77 insertions, 0 deletions

diff --git a/src/migration-scripts/container/0-to-1 b/src/migration-scripts/container/0-to-1
new file mode 100755
index 000000000..d0461389b
--- /dev/null
+++ b/src/migration-scripts/container/0-to-1
@@ -0,0 +1,77 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2022 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# 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 <http://www.gnu.org/licenses/>.
+
+# T4870: change underlaying container filesystem from vfs to overlay
+
+import os
+import shutil
+import sys
+
+from vyos.configtree import ConfigTree
+from vyos.util import call
+
+if (len(sys.argv) < 1):
+    print("Must specify file name!")
+    sys.exit(1)
+
+file_name = sys.argv[1]
+
+with open(file_name, 'r') as f:
+    config_file = f.read()
+
+base = ['container', 'name']
+config = ConfigTree(config_file)
+
+# Check if containers exist and we need to perform image manipulation
+if config.exists(base):
+    for container in config.list_nodes(base):
+        # Stop any given container first
+        call(f'systemctl stop vyos-container-{container}.service')
+        # Export container image for later re-import to new filesystem. We store
+        # the backup on a real disk as a tmpfs (like /tmp) could probably lack
+        # memory if a host has too many containers stored.
+        image_name = config.return_value(base + [container, 'image'])
+        call(f'podman image save --quiet --output /root/{container}.tar --format oci-archive {image_name}')
+
+# No need to adjust the strage driver online (this is only used for testing and
+# debugging on a live system) - it is already overlay2 when the migration script
+# is run during system update. But the specified driver in the image is actually
+# overwritten by the still present VFS filesystem on disk. Thus podman still
+# thinks it uses VFS until we delete the libpod directory under:
+# /usr/lib/live/mount/persistence/container/storage
+#call('sed -i "s/vfs/overlay2/g" /etc/containers/storage.conf /usr/share/vyos/templates/container/storage.conf.j2')
+
+base_path = '/usr/lib/live/mount/persistence/container/storage'
+for dir in ['libpod', 'vfs', 'vfs-containers', 'vfs-images', 'vfs-layers']:
+    if os.path.exists(f'{base_path}/{dir}'):
+        shutil.rmtree(f'{base_path}/{dir}')
+
+# Now all remaining information about VFS is gone and we operate in overlayfs2
+# filesystem mode. Time to re-import the images.
+if config.exists(base):
+    for container in config.list_nodes(base):
+        # Export container image for later re-import to new filesystem
+        image_name = config.return_value(base + [container, 'image'])
+        image_path = f'/root/{container}.tar'
+        call(f'podman image load --quiet --input {image_path}')
+
+        # Start any given container first
+        call(f'systemctl start vyos-container-{container}.service')
+
+        # Delete temporary container image
+        if os.path.exists(image_path):
+            os.unlink(image_path)
+