Files
zfs_autobackup/zfs_autobackup/ZfsAutoverify.py
2022-01-24 16:55:20 +01:00

403 lines
14 KiB
Python

import os
import time
from .ExecuteNode import ExecuteNode
from .ZfsAuto import ZfsAuto
from .ZfsDataset import ZfsDataset
from .ZfsNode import ZfsNode
import sys
import platform
def tmp_name(suffix=""):
"""create temporary name unique to this process and node"""
#we could use uuids but those are ugly and confusing
name="zfstmp_{}_{}".format(platform.node(), os.getpid())
name=name+suffix
return name
def hash_tree_tar(node, path):
"""calculate md5sum of a directory tree, using tar"""
node.debug("Hashing filesystem {} ".format(path))
cmd=[ "tar", "-cf", "-", "-C", path, ".",
ExecuteNode.PIPE, "md5sum"]
stdout = node.run(cmd)
if node.readonly:
hashed=None
else:
hashed = stdout[0].split(" ")[0]
node.debug("Hash of {} filesytem is {}".format(path, hashed))
return hashed
def compare_trees_tar(source_node, source_path, target_node, target_path):
"""compare two trees using tar. compatible and simple"""
source_hash= hash_tree_tar(source_node, source_path)
target_hash= hash_tree_tar(target_node, target_path)
if source_hash != target_hash:
raise Exception("md5hash difference: {} != {}".format(source_hash, target_hash))
def compare_trees_rsync(source_node, source_path, target_node, target_path):
"""use rsync to compare two trees.
Advantage is that we can see which individual files differ.
But requires rsync and cant do remote to remote."""
cmd = ["rsync", "-rcn", "--info=COPY,DEL,MISC,NAME,SYMSAFE", "--msgs2stderr", "--delete" ]
#local
if source_node.ssh_to is None and target_node.ssh_to is None:
cmd.append("{}/".format(source_path))
cmd.append("{}/".format(target_path))
source_node.debug("Running rsync locally, on source.")
stdout, stderr = source_node.run(cmd, return_stderr=True)
#source is local
elif source_node.ssh_to is None and target_node.ssh_to is not None:
cmd.append("{}/".format(source_path))
cmd.append("{}:{}/".format(target_node.ssh_to, target_path))
source_node.debug("Running rsync locally, on source.")
stdout, stderr = source_node.run(cmd, return_stderr=True)
#target is local
elif source_node.ssh_to is not None and target_node.ssh_to is None:
cmd.append("{}:{}/".format(source_node.ssh_to, source_path))
cmd.append("{}/".format(target_path))
source_node.debug("Running rsync locally, on target.")
stdout, stderr=target_node.run(cmd, return_stderr=True)
else:
raise Exception("Source and target cant both be remote when verifying. (rsync limitation)")
if stderr:
raise Exception("Dataset verify failed, see above list for differences")
def verify_filesystem(source_snapshot, source_mnt, target_snapshot, target_mnt, method):
"""Compare the contents of two zfs filesystem snapshots """
try:
# mount the snapshots
source_snapshot.mount(source_mnt)
target_snapshot.mount(target_mnt)
if method=='rsync':
compare_trees_rsync(source_snapshot.zfs_node, source_mnt, target_snapshot.zfs_node, target_mnt)
elif method == 'tar':
compare_trees_tar(source_snapshot.zfs_node, source_mnt, target_snapshot.zfs_node, target_mnt)
else:
raise(Exception("program errror, unknown method"))
finally:
source_snapshot.unmount()
target_snapshot.unmount()
def hash_dev(node, dev):
"""calculate md5sum of a device on a node"""
node.debug("Hashing volume {} ".format(dev))
cmd = [ "md5sum", dev ]
stdout = node.run(cmd)
if node.readonly:
hashed=None
else:
hashed = stdout[0].split(" ")[0]
node.debug("Hash of volume {} is {}".format(dev, hashed))
return hashed
# def activate_volume_snapshot(dataset, snapshot):
# """enables snapdev, waits and tries to findout /dev path to the volume, in a compatible way. (linux/freebsd/smartos)"""
#
# dataset.set("snapdev", "visible")
#
# #NOTE: add smartos location to this list as well
# locations=[
# "/dev/zvol/" + snapshot.name
# ]
#
# dataset.debug("Waiting for /dev entry to appear...")
# time.sleep(0.1)
#
# start_time=time.time()
# while time.time()-start_time<10:
# for location in locations:
# stdout, stderr, exit_code=dataset.zfs_node.run(["test", "-e", location], return_all=True, valid_exitcodes=[0,1])
#
# #fake it in testmode
# if dataset.zfs_node.readonly:
# return location
#
# if exit_code==0:
# return location
# time.sleep(1)
#
# raise(Exception("Timeout while waiting for {} entry to appear.".format(locations)))
#
# def deacitvate_volume_snapshot(dataset):
# dataset.inherit("snapdev")
#NOTE: https://www.google.com/search?q=Mount+Path+Limit+freebsd
#Freebsd has limitations regarding path length, so we cant use the above method.
#Instead we create a temporary clone
def get_tmp_clone_name(snapshot):
pool=snapshot.zfs_node.get_pool(snapshot)
return pool.name+"/"+tmp_name()
def activate_volume_snapshot(snapshot):
"""clone volume, waits and tries to findout /dev path to the volume, in a compatible way. (linux/freebsd/smartos)"""
clone_name=get_tmp_clone_name(snapshot)
clone=snapshot.clone(clone_name)
#NOTE: add smartos location to this list as well
locations=[
"/dev/zvol/" + clone_name
]
clone.debug("Waiting for /dev entry to appear...")
time.sleep(0.1)
start_time=time.time()
while time.time()-start_time<10:
for location in locations:
stdout, stderr, exit_code=clone.zfs_node.run(["test", "-e", location], return_all=True, valid_exitcodes=[0,1])
#fake it in testmode
if clone.zfs_node.readonly:
return location
if exit_code==0:
return location
time.sleep(1)
raise(Exception("Timeout while waiting for {} entry to appear.".format(locations)))
def deacitvate_volume_snapshot(snapshot):
clone_name=get_tmp_clone_name(snapshot)
clone=snapshot.zfs_node.get_dataset(clone_name)
clone.destroy()
def verify_volume(source_dataset, source_snapshot, target_dataset, target_snapshot):
"""compare the contents of two zfs volume snapshots"""
try:
source_dev= activate_volume_snapshot(source_snapshot)
target_dev= activate_volume_snapshot(target_snapshot)
source_hash= hash_dev(source_snapshot.zfs_node, source_dev)
target_hash= hash_dev(target_snapshot.zfs_node, target_dev)
if source_hash!=target_hash:
raise Exception("md5hash difference: {} != {}".format(source_hash, target_hash))
finally:
deacitvate_volume_snapshot(source_snapshot)
deacitvate_volume_snapshot(target_snapshot)
def create_mountpoints(source_node, target_node):
# prepare mount points
source_node.debug("Create temporary mount point")
source_mnt = "/tmp/"+tmp_name("source")
source_node.run(["mkdir", source_mnt])
target_node.debug("Create temporary mount point")
target_mnt = "/tmp/"+tmp_name("target")
target_node.run(["mkdir", target_mnt])
return source_mnt, target_mnt
def cleanup_mountpoint(node, mnt):
node.debug("Cleaning up temporary mount point")
node.run([ "rmdir", mnt ], hide_errors=True, valid_exitcodes=[] )
class ZfsAutoverify(ZfsAuto):
"""The zfs-autoverify class, default agruments and stuff come from ZfsAuto"""
def __init__(self, argv, print_arguments=True):
# NOTE: common options and parameters are in ZfsAuto
super(ZfsAutoverify, self).__init__(argv, print_arguments)
def parse_args(self, argv):
"""do extra checks on common args"""
args=super(ZfsAutoverify, self).parse_args(argv)
if args.target_path == None:
self.log.error("Please specify TARGET-PATH")
sys.exit(255)
return args
def get_parser(self):
"""extend common parser with extra stuff needed for zfs-autobackup"""
parser=super(ZfsAutoverify, self).get_parser()
group=parser.add_argument_group("Verify options")
group.add_argument('--fs-compare', metavar='METHOD', default="tar", choices=["tar", "rsync"],
help='Compare method to use for filesystems. (tar, rsync) Default: %(default)s ')
return parser
def verify_datasets(self, source_mnt, source_datasets, target_node, target_mnt):
fail_count=0
count = 0
for source_dataset in source_datasets:
# stats
if self.args.progress:
count = count + 1
self.progress("Analysing dataset {}/{} ({} failed)".format(count, len(source_datasets), fail_count))
try:
# determine corresponding target_dataset
target_name = self.make_target_name(source_dataset)
target_dataset = target_node.get_dataset(target_name)
# find common snapshots to verify
source_snapshot = source_dataset.find_common_snapshot(target_dataset)
target_snapshot = target_dataset.find_snapshot(source_snapshot)
if source_snapshot is None or target_snapshot is None:
raise(Exception("Cant find common snapshot"))
target_snapshot.verbose("Verifying...")
if source_dataset.properties['type']=="filesystem":
verify_filesystem(source_snapshot, source_mnt, target_snapshot, target_mnt, self.args.fs_compare)
elif source_dataset.properties['type']=="volume":
verify_volume(source_dataset, source_snapshot, target_dataset, target_snapshot)
else:
raise(Exception("{} has unknown type {}".format(source_dataset, source_dataset.properties['type'])))
except Exception as e:
if self.args.progress:
self.clear_progress()
fail_count = fail_count + 1
target_dataset.error("FAILED: " + str(e))
if self.args.debug:
self.verbose("Debug mode, aborting on first error")
raise
if self.args.progress:
self.clear_progress()
return fail_count
def run(self):
source_node=None
source_mnt=None
target_node=None
target_mnt=None
try:
################ create source zfsNode
self.set_title("Source settings")
description = "[Source]"
source_node = ZfsNode(snapshot_time_format=self.snapshot_time_format, hold_name=self.hold_name, logger=self,
ssh_config=self.args.ssh_config,
ssh_to=self.args.ssh_source, readonly=self.args.test,
debug_output=self.args.debug_output, description=description)
################# select source datasets
self.set_title("Selecting")
source_datasets = source_node.selected_datasets(property_name=self.property_name,
exclude_received=self.args.exclude_received,
exclude_paths=self.exclude_paths,
exclude_unchanged=self.args.exclude_unchanged,
min_change=0)
if not source_datasets:
self.print_error_sources()
return 255
# create target_node
self.set_title("Target settings")
target_node = ZfsNode(snapshot_time_format=self.snapshot_time_format, hold_name=self.hold_name,
logger=self, ssh_config=self.args.ssh_config,
ssh_to=self.args.ssh_target,
readonly=self.args.test, debug_output=self.args.debug_output,
description="[Target]")
target_node.verbose("Verify datasets under: {}".format(self.args.target_path))
self.set_title("Verifying")
source_mnt, target_mnt= create_mountpoints(source_node, target_node)
fail_count = self.verify_datasets(
source_mnt=source_mnt,
source_datasets=source_datasets,
target_mnt=target_mnt,
target_node=target_node)
if not fail_count:
if self.args.test:
self.set_title("All tests successful.")
else:
self.set_title("All datasets verified ok")
else:
if fail_count != 255:
self.error("{} dataset(s) failed!".format(fail_count))
if self.args.test:
self.verbose("")
self.warning("TEST MODE - DID NOT VERIFY ANYTHING!")
return fail_count
except Exception as e:
self.error("Exception: " + str(e))
if self.args.debug:
raise
return 255
except KeyboardInterrupt:
self.error("Aborted")
return 255
finally:
# cleanup
if source_mnt is not None:
cleanup_mountpoint(source_node, source_mnt)
if target_mnt is not None:
cleanup_mountpoint(target_node, target_mnt)
def cli():
import sys
sys.exit(ZfsAutoverify(sys.argv[1:], False).run())
if __name__ == "__main__":
cli()