1 files changed, 122 insertions, 0 deletions
diff --git a/python/vyos/system/raid.py b/python/vyos/system/raid.py
new file mode 100644
index 000000000..5b33d34da
--- /dev/null
+++ b/python/vyos/system/raid.py
@@ -0,0 +1,122 @@
+# Copyright 2023 VyOS maintainers and contributors <maintainers@vyos.io>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+"""RAID related functions"""
+
+from pathlib import Path
+from shutil import copy
+from dataclasses import dataclass
+
+from vyos.utils.process import cmd, run
+from vyos.system import disk
+
+
+@dataclass
+class RaidDetails:
+    """RAID type"""
+    name: str
+    level: str
+    members: list[str]
+    disks: list[disk.DiskDetails]
+
+
+def raid_create(raid_members: list[str],
+                raid_name: str = 'md0',
+                raid_level: str = 'raid1') -> None:
+    """Create a RAID array
+
+    Args:
+        raid_name (str): a name of array (data, backup, test, etc.)
+        raid_members (list[str]): a list of array members
+        raid_level (str, optional): an array level. Defaults to 'raid1'.
+    """
+    raid_devices_num: int = len(raid_members)
+    raid_members_str: str = ' '.join(raid_members)
+    for part in raid_members:
+        drive: str = disk.partition_parent(part)
+        # set partition type GUID for raid member; cf.
+        # https://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_type_GUIDs
+        command: str = f'sgdisk --typecode=3:A19D880F-05FC-4D3B-A006-743F0F84911E {drive}'
+        cmd(command)
+    command: str = f'mdadm --create /dev/{raid_name} -R --metadata=1.0 \
+        --raid-devices={raid_devices_num} --level={raid_level} \
+        {raid_members_str}'
+
+    cmd(command)
+
+    raid = RaidDetails(
+        name = f'/dev/{raid_name}',
+        level = raid_level,
+        members = raid_members,
+        disks = [disk.from_partition(m) for m in raid_members]
+    )
+
+    return raid
+
+def clear():
+    """Deactivate all RAID arrays"""
+    command: str = 'mdadm --examine --scan'
+    raid_config = cmd(command)
+    if not raid_config:
+        return
+    command: str = 'mdadm --run /dev/md?*'
+    run(command)
+    command: str = 'mdadm --assemble --scan --auto=yes --symlink=no'
+    run(command)
+    command: str = 'mdadm --stop --scan'
+    run(command)
+
+
+def update_initramfs() -> None:
+    """Update initramfs"""
+    mdadm_script = '/etc/initramfs-tools/scripts/local-top/mdadm'
+    copy('/usr/share/initramfs-tools/scripts/local-block/mdadm', mdadm_script)
+    p = Path(mdadm_script)
+    p.write_text(p.read_text().replace('$((COUNT + 1))', '20'))
+    command: str = 'update-initramfs -u'
+    cmd(command)
+
+def update_default(target_dir: str) -> None:
+    """Update /etc/default/mdadm to start MD monitoring daemon at boot
+    """
+    source_mdadm_config = '/etc/default/mdadm'
+    target_mdadm_config = Path(target_dir).joinpath('/etc/default/mdadm')
+    target_mdadm_config_dir = Path(target_mdadm_config).parent
+    Path.mkdir(target_mdadm_config_dir, parents=True, exist_ok=True)
+    s = Path(source_mdadm_config).read_text().replace('START_DAEMON=false',
+                                                      'START_DAEMON=true')
+    Path(target_mdadm_config).write_text(s)
+
+def get_uuid(device: str) -> str:
+    """Get UUID of a device"""
+    command: str = f'tune2fs -l {device}'
+    l = cmd(command).splitlines()
+    uuid = next((x for x in l if x.startswith('Filesystem UUID')), '')
+    return uuid.split(':')[1].strip() if uuid else ''
+
+def get_uuids(raid_details: RaidDetails) -> tuple[str]:
+    """Get UUIDs of RAID members
+
+    Args:
+        raid_name (str): a name of array (data, backup, test, etc.)
+
+    Returns:
+        tuple[str]: root_disk uuid, root_md uuid
+    """
+    raid_name: str = raid_details.name
+    root_partition: str = raid_details.members[0]
+    uuid_root_disk: str = get_uuid(root_partition)
+    uuid_root_md: str = get_uuid(raid_name)
+    return uuid_root_disk, uuid_root_md