pre/post cmd tests

Add support for pre- and post-snapshot scripts (#39)

.github/workflows/regression.yml

@@ -17,7 +17,7 @@ jobs:
 
 
       - name: Prepare
-        run: sudo apt update && sudo apt install zfsutils-linux lzop pigz zstd gzip xz-utils lz4 && sudo -H pip3 install coverage unittest2 mock==3.0.5 coveralls
+        run: sudo apt update && sudo apt install zfsutils-linux lzop pigz zstd gzip xz-utils lz4 mbuffer && sudo -H pip3 install coverage unittest2 mock==3.0.5 coveralls
 
 
       - name: Regression test
@@ -39,7 +39,7 @@ jobs:
 
 
       - name: Prepare
-        run: sudo apt update && sudo apt install zfsutils-linux python3-setuptools lzop pigz zstd gzip xz-utils liblz4-tool && sudo -H pip3 install coverage unittest2 mock==3.0.5 coveralls
+        run: sudo apt update && sudo apt install zfsutils-linux python3-setuptools lzop pigz zstd gzip xz-utils liblz4-tool mbuffer && sudo -H pip3 install coverage unittest2 mock==3.0.5 coveralls
 
 
       - name: Regression test
@@ -64,7 +64,7 @@ jobs:
           python-version: '2.x'
 
       - name: Prepare
-        run: sudo apt update && sudo apt install zfsutils-linux python-setuptools lzop pigz zstd gzip xz-utils liblz4-tool && sudo -H pip install coverage unittest2 mock==3.0.5 coveralls colorama
+        run: sudo apt update && sudo apt install zfsutils-linux python-setuptools lzop pigz zstd gzip xz-utils liblz4-tool mbuffer && sudo -H pip install coverage unittest2 mock==3.0.5 coveralls colorama
 
       - name: Regression test
         run: sudo -E ./tests/run_tests

README.md

@@ -5,7 +5,7 @@
 
 ## Introduction
 
-This is a tool I wrote to make replicating ZFS datasets easy and reliable.
+ZFS-autobackup tries to be the most reliable and easiest to use tool, while having all the features.
 
 You can either use it as a **backup** tool, **replication** tool or **snapshot** tool.
 
@@ -13,12 +13,10 @@ You can select what to backup by setting a custom `ZFS property`. This makes it
 
 Other settings are just specified on the commandline: Simply setup and test your zfs-autobackup command and  fix all the issues you might encounter. When you're done you can just copy/paste your command to a cron or script.
 
-Since its using ZFS commands, you can see what its actually doing by specifying `--debug`. This also helps a lot if you run into some strange problem or error. You can just copy-paste the command that fails and play around with it on the commandline. (something I missed in other tools)
+Since its using ZFS commands, you can see what it's actually doing by specifying `--debug`. This also helps a lot if you run into some strange problem or error. You can just copy-paste the command that fails and play around with it on the commandline. (something I missed in other tools)
 
 An important feature thats missing from other tools is a reliable `--test` option: This allows you to see what zfs-autobackup will do and tune your parameters. It will do everything, except make changes to your system.
 
-zfs-autobackup tries to be the easiest to use backup tool for zfs, with the most features.
-
 ## Features
 
 * Works across operating systems: Tested with **Linux**, **FreeBSD/FreeNAS** and **SmartOS**.
@@ -34,6 +32,9 @@ zfs-autobackup tries to be the easiest to use backup tool for zfs, with the most
 * Can be scheduled via a simple cronjob or run directly from commandline.
 * Supports resuming of interrupted transfers.
 * ZFS encryption support: Can decrypt / encrypt or even re-encrypt datasets during transfer.
+* Supports sending with compression. (Using pigz, zstd etc)
+* IO buffering to speed up transfer.
+* Bandwidth rate limiting.
 * Multiple backups from and to the same datasets are no problem.
 * Creates the snapshot before doing anything else. (assuring you at least have a snapshot if all else fails)
 * Checks everything but tries continue on non-fatal errors when possible. (Reports error-count when done)
@@ -44,10 +45,11 @@ zfs-autobackup tries to be the easiest to use backup tool for zfs, with the most
 * Automatic resuming of failed transfers.
 * Can continue from existing common snapshots. (e.g. easy migration)
 * Gracefully handles datasets that no longer exist on source.
+* Support for ZFS sending/receiving through custom pipes.
 * Easy installation:
-  * Just install zfs-autobackup via pip, or download it manually.
+  * Just install zfs-autobackup via pip.
   * Only needs to be installed on one side.
-  * Written in python and uses zfs-commands, no 3rd party dependency's or libraries needed.
+  * Written in python and uses zfs-commands, no special 3rd party dependency's or compiled libraries needed.
   * No separate config files or properties. Just one zfs-autobackup command you can copy/paste in your backup script.
 
 ## Installation
@@ -396,6 +398,47 @@ Note 2: Decide what you want at an early stage: If you change the --encrypt or -
 
 I'll add some tips when the issues start to get in on github. :)
 
+## Transfer buffering, compression and rate limiting.
+
+If you're transferring over a slow link it might be useful to use `--compress=zstd-fast`. This will compress the data before sending, so it uses less bandwidth. An alternative to this is to use --zfs-compressed: This will transfer blocks that already have compression intact. (--compress will usually compress much better but uses much more resources. --zfs-compressed uses the least resources, but can be a disadvantage if you want to use a different compression method on the target.)
+
+You can also limit the datarate by using the `--rate` option.
+
+The `--buffer` option might also help since it acts as an IO buffer: zfs send can vary wildly between completely idle and huge bursts of data. When zfs send is idle, the buffer will continue transferring data over the slow link.
+
+It's also possible to add custom send or receive pipes with `--send-pipe` and `--recv-pipe`.
+
+These options all work together and the buffer on the receiving side is only added if appropriate. When all options are active:
+
+#### On the sending side:
+
+zfs send -> send buffer -> custom send pipes -> compression -> transfer rate limiter
+
+#### On the receiving side:
+decompression -> custom recv pipes -> buffer -> zfs recv
+
+## Running custom commands before and after snapshotting
+
+You can run commands before and after the snapshot to freeze databases to make the on for example to make the on-disk data consistent before snapshotting.
+
+The commands will be executed on the source side. Use the `--pre-snapshot-cmd` and `--post-snapshot-cmd` options for this.
+
+For example:
+
+```sh
+zfs-autobackup \
+    --pre-snapshot-cmd 'daemon -f jexec mysqljail1 mysql -s -e "set autocommit=0;flush logs;flush tables with read lock;\\! echo \$\$ > /tmp/mysql_lock.pid && sleep 60"' \
+    --pre-snapshot-cmd 'daemon -f jexec mysqljail2 mysql -s -e "set autocommit=0;flush logs;flush tables with read lock;\\! echo \$\$ > /tmp/mysql_lock.pid && sleep 60"' \
+    --post-snapshot-cmd 'pkill -F /jails/mysqljail1/tmp/mysql_lock.pid' \
+    --post-snapshot-cmd 'pkill -F /jails/mysqljail2/tmp/mysql_lock.pid' \
+    backupfs1
+```
+
+Failure handling during pre/post commands:
+
+* If a pre-command fails, zfs-autobackup will exit with an error. (after executing the post-commands)
+* All post-commands are always executed. Even if the pre-commands or actual snapshot have failed. This way you can be sure that stuff is always cleanedup and unfreezed.
+
 ## Tips
 
 * Use ```--debug``` if something goes wrong and you want to see the commands that are executed. This will also stop at the first error.
@@ -408,6 +451,8 @@ I'll add some tips when the issues start to get in on github. :)
 
 If you have a large number of datasets its important to keep the following tips in mind.
 
+Also it might help to use the --buffer option to add IO buffering during the data transfer. This might speed up things since it smooths out sudden IO bursts that are frequent during a zfs send or recv.
+
 #### Some statistics
 
 To get some idea of how fast zfs-autobackup is, I did some test on my laptop, with a SKHynix_HFS512GD9TNI-L2B0B disk. I'm using zfs 2.0.2.  
@@ -468,17 +513,32 @@ Look in man ssh_config for many more options.
 (NOTE: Quite a lot has changed since the current stable version 3.0. The page your are viewing is for upcoming version 3.1 which is still in beta.)
 
 ```console
-usage: zfs-autobackup [-h] [--ssh-config CONFIG-FILE] [--ssh-source USER@HOST] [--ssh-target USER@HOST] [--keep-source SCHEDULE] [--keep-target SCHEDULE] [--other-snapshots] [--no-snapshot] [--no-send]
+usage: zfs-autobackup [-h] [--ssh-config CONFIG-FILE] [--ssh-source USER@HOST]
-                   [--no-thinning] [--no-holds] [--min-change BYTES] [--allow-empty] [--ignore-replicated] [--strip-path N] [--clear-refreservation] [--clear-mountpoint] [--filter-properties PROPERY,...]
+                      [--ssh-target USER@HOST] [--keep-source SCHEDULE]
-                   [--set-properties PROPERTY=VALUE,...] [--rollback] [--destroy-incompatible] [--destroy-missing SCHEDULE] [--ignore-transfer-errors] [--decrypt] [--encrypt] [--test] [--verbose] [--debug]
+                      [--keep-target SCHEDULE] [--pre-snapshot-cmd COMMAND]
-                   [--debug-output] [--progress] [--send-pipe COMMAND] [--recv-pipe COMMAND]
+                      [--post-snapshot-cmd COMMAND] [--other-snapshots]
-                   backup-name [target-path]
+                      [--no-snapshot] [--no-send] [--no-thinning] [--no-holds]
+                      [--min-change BYTES] [--allow-empty]
+                      [--ignore-replicated] [--strip-path N]
+                      [--clear-refreservation] [--clear-mountpoint]
+                      [--filter-properties PROPERY,...]
+                      [--set-properties PROPERTY=VALUE,...] [--rollback]
+                      [--destroy-incompatible] [--destroy-missing SCHEDULE]
+                      [--ignore-transfer-errors] [--decrypt] [--encrypt]
+                      [--test] [--verbose] [--debug] [--debug-output]
+                      [--progress] [--send-pipe COMMAND] [--recv-pipe COMMAND]
+                      [--compress TYPE] [--rate DATARATE] [--buffer SIZE]
+                      backup-name [target-path]
 
-zfs-autobackup v3.1-beta3 - Copyright 2020 E.H.Eefting (edwin@datux.nl)
+zfs-autobackup v3.1-beta6 - (c)2021 E.H.Eefting (edwin@datux.nl)
 
 positional arguments:
-  backup-name           Name of the backup (you should set the zfs property "autobackup:backup-name" to true on filesystems you want to backup
+  backup-name           Name of the backup (you should set the zfs property
-  target-path           Target ZFS filesystem (optional: if not specified, zfs-autobackup will only operate as snapshot-tool on source)
+                        "autobackup:backup-name" to true on filesystems you
+                        want to backup
+  target-path           Target ZFS filesystem (optional: if not specified,
+                        zfs-autobackup will only operate as snapshot-tool on
+                        source)
 
 optional arguments:
   -h, --help            show this help message and exit
@@ -489,41 +549,84 @@ optional arguments:
   --ssh-target USER@HOST
                         Target host to push backup to.
   --keep-source SCHEDULE
-                        Thinning schedule for old source snapshots. Default: 10,1d1w,1w1m,1m1y
+                        Thinning schedule for old source snapshots. Default:
+                        10,1d1w,1w1m,1m1y
   --keep-target SCHEDULE
-                        Thinning schedule for old target snapshots. Default: 10,1d1w,1w1m,1m1y
+                        Thinning schedule for old target snapshots. Default:
-  --other-snapshots     Send over other snapshots as well, not just the ones created by this tool.
+                        10,1d1w,1w1m,1m1y
-  --no-snapshot         Don't create new snapshots (useful for finishing uncompleted backups, or cleanups)
+  --pre-snapshot-cmd COMMAND
-  --no-send             Don't send snapshots (useful for cleanups, or if you want a serperate send-cronjob)
+                        Run COMMAND before snapshotting (can be used multiple
+                        times.
+  --post-snapshot-cmd COMMAND
+                        Run COMMAND after snapshotting (can be used multiple
+                        times.
+  --other-snapshots     Send over other snapshots as well, not just the ones
+                        created by this tool.
+  --no-snapshot         Don't create new snapshots (useful for finishing
+                        uncompleted backups, or cleanups)
+  --no-send             Don't send snapshots (useful for cleanups, or if you
+                        want a serperate send-cronjob)
   --no-thinning         Do not destroy any snapshots.
-  --no-holds            Don't hold snapshots. (Faster. Allows you to destroy common snapshot.)
+  --no-holds            Don't hold snapshots. (Faster. Allows you to destroy
-  --min-change BYTES    Number of bytes written after which we consider a dataset changed (default 1)
+                        common snapshot.)
-  --allow-empty         If nothing has changed, still create empty snapshots. (same as --min-change=0)
+  --min-change BYTES    Number of bytes written after which we consider a
-  --ignore-replicated   Ignore datasets that seem to be replicated some other way. (No changes since lastest snapshot. Useful for proxmox HA replication)
+                        dataset changed (default 1)
-  --strip-path N        Number of directories to strip from target path (use 1 when cloning zones between 2 SmartOS machines)
+  --allow-empty         If nothing has changed, still create empty snapshots.
+                        (same as --min-change=0)
+  --ignore-replicated   Ignore datasets that seem to be replicated some other
+                        way. (No changes since lastest snapshot. Useful for
+                        proxmox HA replication)
+
+  --strip-path N        Number of directories to strip from target path (use 1
+                        when cloning zones between 2 SmartOS machines)
   --clear-refreservation
-                        Filter "refreservation" property. (recommended, safes space. same as --filter-properties refreservation)
+                        Filter "refreservation" property. (recommended, safes
-  --clear-mountpoint    Set property canmount=noauto for new datasets. (recommended, prevents mount conflicts. same as --set-properties canmount=noauto)
+                        space. same as --filter-properties refreservation)
+  --clear-mountpoint    Set property canmount=noauto for new datasets.
+                        (recommended, prevents mount conflicts. same as --set-
+                        properties canmount=noauto)
   --filter-properties PROPERY,...
-                        List of properties to "filter" when receiving filesystems. (you can still restore them with zfs inherit -S)
+                        List of properties to "filter" when receiving
+                        filesystems. (you can still restore them with zfs
+                        inherit -S)
   --set-properties PROPERTY=VALUE,...
-                        List of propererties to override when receiving filesystems. (you can still restore them with zfs inherit -S)
+                        List of propererties to override when receiving
-  --rollback            Rollback changes to the latest target snapshot before starting. (normally you can prevent changes by setting the readonly property on the target_path to on)
+                        filesystems. (you can still restore them with zfs
+                        inherit -S)
+  --rollback            Rollback changes to the latest target snapshot before
+                        starting. (normally you can prevent changes by setting
+                        the readonly property on the target_path to on)
   --destroy-incompatible
-                        Destroy incompatible snapshots on target. Use with care! (implies --rollback)
+                        Destroy incompatible snapshots on target. Use with
+                        care! (implies --rollback)
   --destroy-missing SCHEDULE
-                        Destroy datasets on target that are missing on the source. Specify the time since the last snapshot, e.g: --destroy-missing 30d
+                        Destroy datasets on target that are missing on the
+                        source. Specify the time since the last snapshot, e.g:
+                        --destroy-missing 30d
   --ignore-transfer-errors
-                        Ignore transfer errors (still checks if received filesystem exists. useful for acltype errors)
+                        Ignore transfer errors (still checks if received
+                        filesystem exists. useful for acltype errors)
   --decrypt             Decrypt data before sending it over.
   --encrypt             Encrypt data after receiving it.
-  --test                dont change anything, just show what would be done (still does all read-only operations)
+  --test                dont change anything, just show what would be done
+                        (still does all read-only operations)
   --verbose             verbose output
-  --debug               Show zfs commands that are executed, stops after an exception.
+  --debug               Show zfs commands that are executed, stops after an
+                        exception.
   --debug-output        Show zfs commands and their output/exit codes. (noisy)
-  --progress            show zfs progress output. Enabled automaticly on ttys. (use --no-progress to disable)
+  --progress            show zfs progress output. Enabled automaticly on ttys.
-  --send-pipe COMMAND   pipe zfs send output through COMMAND
+                        (use --no-progress to disable)
-  --recv-pipe COMMAND   pipe zfs recv input through COMMAND
+  --send-pipe COMMAND   pipe zfs send output through COMMAND (can be used
+                        multiple times)
+  --recv-pipe COMMAND   pipe zfs recv input through COMMAND (can be used
+                        multiple times)
+  --compress TYPE       Use compression during transfer, zstd-fast
+                        recommended. (zstd-slow, xz, pigz-fast, lz4, pigz-
+                        slow, zstd-fast, gzip, lzo)
+  --rate DATARATE       Limit data transfer rate (e.g. 128K. requires
+                        mbuffer.)
+  --buffer SIZE         Add zfs send and recv buffers to smooth out IO bursts.
+                        (e.g. 128M. requires mbuffer)
 
 Full manual at: https://github.com/psy0rz/zfs_autobackup
 ```

tests/basetest.py

@@ -1,4 +1,6 @@
 
+# To run tests as non-root, use this hack:
+# chmod 4755 /usr/sbin/zpool /usr/sbin/zfs
 
 import subprocess
 import random

tests/test_cmdpipe.py

@@ -21,7 +21,7 @@ class TestCmdPipe(unittest2.TestCase):
         p=CmdPipe(readonly=False, inp="test")
         err=[]
         out=[]
-        p.add(CmdItem(["echo", "test"], stderr_handler=lambda line: err.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,0)))
+        p.add(CmdItem(["cat"], stderr_handler=lambda line: err.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,0)))
         executed=p.execute(stdout_handler=lambda line: out.append(line))
 
         self.assertEqual(err, [])

tests/test_externalfailures.py

@@ -227,11 +227,11 @@ test_target1/test_source2/fs2/sub@test-20101111000000
                 # incremental, doesnt want previous anymore
                 with patch('time.strftime', return_value="20101111000002"):
                     self.assertFalse(ZfsAutobackup(
-                        "test test_target1 --no-progress --verbose --keep-target=0 --debug --allow-empty".split(" ")).run())
+                        "test test_target1 --no-progress --verbose --keep-target=0 --allow-empty".split(" ")).run())
 
             print(buf.getvalue())
 
-            self.assertIn(": aborting resume, since", buf.getvalue())
+            self.assertIn("Aborting resume, we dont want that snapshot anymore.", buf.getvalue())
 
         r = shelltest("zfs list -H -o name -r -t all test_target1")
         self.assertMultiLineEqual(r, """
@@ -247,6 +247,34 @@ test_target1/test_source2/fs2/sub
 test_target1/test_source2/fs2/sub@test-20101111000002
 """)
 
+    # test with empty snapshot list (this was a bug)
+    def test_abort_resume_emptysnapshotlist(self):
+
+        if "0.6.5" in ZFS_USERSPACE:
+            self.skipTest("Resume not supported in this ZFS userspace version")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose".split(" ")).run())
+
+        # generate resume
+        with patch('time.strftime', return_value="20101111000001"):
+            self.generate_resume()
+
+        shelltest("zfs destroy test_source1/fs1@test-20101111000001")
+
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                # incremental, doesnt want previous anymore
+                with patch('time.strftime', return_value="20101111000002"):
+                    self.assertFalse(ZfsAutobackup(
+                        "test test_target1 --no-progress --verbose --no-snapshot".split(
+                            " ")).run())
+
+            print(buf.getvalue())
+
+            self.assertIn("Aborting resume, its obsolete", buf.getvalue())
+
+
     def test_missing_common(self):
 
         with patch('time.strftime', return_value="20101111000000"):

tests/test_sendrecvpipes.py

@@ -47,3 +47,42 @@ class TestSendRecvPipes(unittest2.TestCase):
                     self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--compress="+compress]).run())
 
                 shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+    def test_buffer(self):
+        """test different buffer configurations"""
+
+
+        with self.subTest("local local pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--buffer=1M" ]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("remote local pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--ssh-source=localhost", "--buffer=1M"]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("local remote pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1",  "--exclude-received", "--no-holds", "--no-progress", "--ssh-target=localhost", "--buffer=1M"]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("remote remote pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1",  "--exclude-received", "--no-holds", "--no-progress", "--ssh-source=localhost", "--ssh-target=localhost", "--buffer=1M"]).run())
+
+    def test_rate(self):
+        """test rate limit"""
+
+
+        start=time.time()
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--rate=50k" ]).run())
+
+        #not a great way of verifying but it works.
+        self.assertGreater(time.time()-start, 5)
+
+

tests/test_zfsautobackup.py

@@ -890,7 +890,7 @@ test_target1/test_source2/fs2/sub@test-20101111000003
         n=ZfsNode("test",l)
         d=ZfsDataset(n,"test_source1@test")
 
-        sp=d.send_pipe([], prev_snapshot=None, resume_token=None, show_progress=True, raw=False, send_pipes=[], send_properties=True, write_embedded=True)
+        sp=d.send_pipe([], prev_snapshot=None, resume_token=None, show_progress=True, raw=False, send_pipes=[], send_properties=True, write_embedded=True, zfs_compressed=True)
 
 
         with OutputIO() as buf:

tests/test_zfsautobackup31.py

@@ -71,4 +71,11 @@ test_target1/b/test_source1/fs1/sub@test-20101111000000
 test_target1/b/test_source2/fs2/sub@test-20101111000000
 test_target1/b/test_target1/a/test_source1/fs1@test-20101111000000
 test_target1/b/test_target1/a/test_source1/fs1/sub@test-20101111000000
-""")
+""")
+
+    def test_zfs_compressed(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(
+                ZfsAutobackup("test test_target1 --no-progress --verbose --debug --zfs-compressed".split(" ")).run())
+

tests/test_zfsnode.py

@@ -1,6 +1,6 @@
 from basetest import *
 from zfs_autobackup.LogStub import LogStub
-
+from zfs_autobackup.ExecuteNode import ExecuteError
 
 
 class TestZfsNode(unittest2.TestCase):
@@ -9,16 +9,15 @@ class TestZfsNode(unittest2.TestCase):
         prepare_zpools()
         # return super().setUp()
 
-
     def test_consistent_snapshot(self):
-        logger=LogStub()
+        logger = LogStub()
-        description="[Source]"
+        description = "[Source]"
-        node=ZfsNode("test", logger, description=description)
+        node = ZfsNode("test", logger, description=description)
 
         with self.subTest("first snapshot"):
-            node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",100000)
+            node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1", 100000)
-            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            r = shelltest("zfs list -H -o name -r -t all " + TEST_POOLS)
-            self.assertEqual(r,"""
+            self.assertEqual(r, """
 test_source1
 test_source1/fs1
 test_source1/fs1@test-1
@@ -33,11 +32,10 @@ test_source2/fs3/sub
 test_target1
 """)
 
-
         with self.subTest("second snapshot, no changes, no snapshot"):
-            node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2",1)
+            node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2", 1)
-            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            r = shelltest("zfs list -H -o name -r -t all " + TEST_POOLS)
-            self.assertEqual(r,"""
+            self.assertEqual(r, """
 test_source1
 test_source1/fs1
 test_source1/fs1@test-1
@@ -53,9 +51,9 @@ test_target1
 """)
 
         with self.subTest("second snapshot, no changes, empty snapshot"):
-            node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2",0)
+            node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-2", 0)
-            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            r = shelltest("zfs list -H -o name -r -t all " + TEST_POOLS)
-            self.assertEqual(r,"""
+            self.assertEqual(r, """
 test_source1
 test_source1/fs1
 test_source1/fs1@test-1
@@ -73,31 +71,82 @@ test_source2/fs3/sub
 test_target1
 """)
 
+    def test_consistent_snapshot_prepostcmds(self):
+        logger = LogStub()
+        description = "[Source]"
+        node = ZfsNode("test", logger, description=description, debug_output=True)
+
+        with self.subTest("Test if all cmds are executed correctly (no failures)"):
+            with OutputIO() as buf:
+                with redirect_stdout(buf):
+                    node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",
+                                             0,
+                                             pre_snapshot_cmds=["echo pre1", "echo pre2"],
+                                             post_snapshot_cmds=["echo post1 >&2", "echo post2 >&2"]
+                                             )
+
+                self.assertIn("STDOUT > pre1", buf.getvalue())
+                self.assertIn("STDOUT > pre2", buf.getvalue())
+                self.assertIn("STDOUT > post1", buf.getvalue())
+                self.assertIn("STDOUT > post2", buf.getvalue())
+
+
+        with self.subTest("Failure in the middle, only pre1 and both post1 and post2 should be executed, no snapshot should be attempted"):
+            with OutputIO() as buf:
+                with redirect_stdout(buf):
+                    with self.assertRaises(ExecuteError):
+                        node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",
+                                                 0,
+                                                 pre_snapshot_cmds=["echo pre1", "false", "echo pre2"],
+                                                 post_snapshot_cmds=["echo post1", "false", "echo post2"]
+                                                 )
+
+                print(buf.getvalue())
+                self.assertIn("STDOUT > pre1", buf.getvalue())
+                self.assertNotIn("STDOUT > pre2", buf.getvalue())
+                self.assertIn("STDOUT > post1", buf.getvalue())
+                self.assertIn("STDOUT > post2", buf.getvalue())
+
+        with self.subTest("Snapshot fails"):
+            with OutputIO() as buf:
+                with redirect_stdout(buf):
+                    with self.assertRaises(ExecuteError):
+                        #same snapshot name as before so it fails
+                        node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "test-1",
+                                                 0,
+                                                 pre_snapshot_cmds=["echo pre1", "echo pre2"],
+                                                 post_snapshot_cmds=["echo post1", "echo post2"]
+                                                 )
+
+                print(buf.getvalue())
+                self.assertIn("STDOUT > pre1", buf.getvalue())
+                self.assertIn("STDOUT > pre2", buf.getvalue())
+                self.assertIn("STDOUT > post1", buf.getvalue())
+                self.assertIn("STDOUT > post2", buf.getvalue())
+
 
     def test_getselected(self):
-        logger=LogStub()
+        logger = LogStub()
-        description="[Source]"
+        description = "[Source]"
-        node=ZfsNode("test", logger, description=description)
+        node = ZfsNode("test", logger, description=description)
-        s=pformat(node.selected_datasets(exclude_paths=[], exclude_received=False))
+        s = pformat(node.selected_datasets(exclude_paths=[], exclude_received=False))
         print(s)
 
-        #basics
+        # basics
-        self.assertEqual (s, """[(local): test_source1/fs1,
+        self.assertEqual(s, """[(local): test_source1/fs1,
  (local): test_source1/fs1/sub,
  (local): test_source2/fs2/sub]""")
 
-        #caching, so expect same result after changing it
+        # caching, so expect same result after changing it
         subprocess.check_call("zfs set autobackup:test=true test_source2/fs3", shell=True)
-        self.assertEqual (s, """[(local): test_source1/fs1,
+        self.assertEqual(s, """[(local): test_source1/fs1,
  (local): test_source1/fs1/sub,
  (local): test_source2/fs2/sub]""")
 
-
     def test_validcommand(self):
-        logger=LogStub()
+        logger = LogStub()
-        description="[Source]"
+        description = "[Source]"
-        node=ZfsNode("test", logger, description=description)
+        node = ZfsNode("test", logger, description=description)
-
 
         with self.subTest("test invalid option"):
             self.assertFalse(node.valid_command(["zfs", "send", "--invalid-option", "nonexisting"]))
@@ -105,21 +154,19 @@ test_target1
             self.assertTrue(node.valid_command(["zfs", "send", "-v", "nonexisting"]))
 
     def test_supportedsendoptions(self):
-        logger=LogStub()
+        logger = LogStub()
-        description="[Source]"
+        description = "[Source]"
-        node=ZfsNode("test", logger, description=description)
+        node = ZfsNode("test", logger, description=description)
         # -D propably always supported
-        self.assertGreater(len(node.supported_send_options),0)
+        self.assertGreater(len(node.supported_send_options), 0)
-
 
     def test_supportedrecvoptions(self):
-        logger=LogStub()
+        logger = LogStub()
-        description="[Source]"
+        description = "[Source]"
-        #NOTE: this could hang via ssh if we dont close filehandles properly. (which was a previous bug)
+        # NOTE: this could hang via ssh if we dont close filehandles properly. (which was a previous bug)
-        node=ZfsNode("test", logger, description=description, ssh_to='localhost')
+        node = ZfsNode("test", logger, description=description, ssh_to='localhost')
         self.assertIsInstance(node.supported_recv_options, list)
 
 
-
 if __name__ == '__main__':
     unittest.main()

zfs_autobackup/ZfsAutobackup.py

@@ -16,7 +16,7 @@ from zfs_autobackup.ThinnerRule import ThinnerRule
 class ZfsAutobackup:
     """main class"""
 
-    VERSION = "3.1-beta6"
+    VERSION = "3.1-rc4"
     HEADER = "zfs-autobackup v{} - (c)2021 E.H.Eefting (edwin@datux.nl)".format(VERSION)
 
     def __init__(self, argv, print_arguments=True):
@@ -45,6 +45,10 @@ class ZfsAutobackup:
                             help='Target ZFS filesystem (optional: if not specified, zfs-autobackup will only operate '
                                  'as snapshot-tool on source)')
 
+        parser.add_argument('--pre-snapshot-cmd', metavar="COMMAND", default=[], action='append',
+                            help='Run COMMAND before snapshotting (can be used multiple times.')
+        parser.add_argument('--post-snapshot-cmd', metavar="COMMAND", default=[], action='append',
+                            help='Run COMMAND after snapshotting (can be used multiple times.')
         parser.add_argument('--other-snapshots', action='store_true',
                             help='Send over other snapshots as well, not just the ones created by this tool.')
         parser.add_argument('--no-snapshot', action='store_true',
@@ -75,7 +79,7 @@ class ZfsAutobackup:
         parser.add_argument('--clear-mountpoint', action='store_true',
                             help='Set property canmount=noauto for new datasets. (recommended, prevents mount '
                                  'conflicts. same as --set-properties canmount=noauto)')
-        parser.add_argument('--filter-properties', metavar='PROPERY,...', type=str,
+        parser.add_argument('--filter-properties', metavar='PROPERTY,...', type=str,
                             help='List of properties to "filter" when receiving filesystems. (you can still restore '
                                  'them with zfs inherit -S)')
         parser.add_argument('--set-properties', metavar='PROPERTY=VALUE,...', type=str,
@@ -99,6 +103,9 @@ class ZfsAutobackup:
         parser.add_argument('--encrypt', action='store_true',
                             help='Encrypt data after receiving it.')
 
+        parser.add_argument('--zfs-compressed', action='store_true',
+                            help='Transfer blocks that already have zfs-compression as-is.')
+
         parser.add_argument('--test', action='store_true',
                             help='dont change anything, just show what would be done (still does all read-only '
                                  'operations)')
@@ -163,9 +170,12 @@ class ZfsAutobackup:
             self.log.error("Target should not start with a /")
             sys.exit(255)
 
-        if args.compress and not args.ssh_source and not args.ssh_target:
+        if args.compress and args.ssh_source is None and args.ssh_target is None:
             self.warning("Using compression, but transfer is local.")
 
+        if args.compress and args.zfs_compressed:
+            self.warning("Using --compress with --zfs-compressed, might be inefficient.")
+
     def verbose(self, txt):
         self.log.verbose(txt)
 
@@ -323,6 +333,13 @@ class ZfsAutobackup:
             ret.append(ExecuteNode.PIPE)
             logger("zfs recv custom pipe   : {}".format(recv_pipe))
 
+        # IO buffer
+        if self.args.buffer:
+            #only add second buffer if its usefull. (e.g. non local transfer or other pipes active)
+            if self.args.ssh_source!=None or self.args.ssh_target!=None or self.args.recv_pipe or self.args.send_pipe or self.args.compress!=None:
+                logger("zfs recv buffer        : {}".format(self.args.buffer))
+                ret.extend(["mbuffer", "-q", "-s128k", "-m"+self.args.buffer,  ExecuteNode.PIPE ])
+
         return ret
 
     # NOTE: this method also uses self.args. args that need extra processing are passed as function parameters:
@@ -374,7 +391,7 @@ class ZfsAutobackup:
                                               no_send=self.args.no_send,
                                               destroy_incompatible=self.args.destroy_incompatible,
                                               send_pipes=send_pipes, recv_pipes=recv_pipes,
-                                              decrypt=self.args.decrypt, encrypt=self.args.encrypt, )
+                                              decrypt=self.args.decrypt, encrypt=self.args.encrypt, zfs_compressed=self.args.zfs_compressed )
             except Exception as e:
                 fail_count = fail_count + 1
                 source_dataset.error("FAILED: " + str(e))
@@ -457,7 +474,7 @@ class ZfsAutobackup:
                                   ssh_to=self.args.ssh_source, readonly=self.args.test,
                                   debug_output=self.args.debug_output, description=description, thinner=source_thinner)
             source_node.verbose(
-                "Selects all datasets that have property 'autobackup:{}=true' (or childs of datasets that have "
+                "Selects all datasets that have property 'autobackup:{}=true' (or children of datasets that have "
                 "'autobackup:{}=child')".format(
                     self.args.backup_name, self.args.backup_name))
 
@@ -493,7 +510,9 @@ class ZfsAutobackup:
             if not self.args.no_snapshot:
                 self.set_title("Snapshotting")
                 source_node.consistent_snapshot(source_datasets, source_node.new_snapshotname(),
-                                                min_changed_bytes=self.args.min_change)
+                                                min_changed_bytes=self.args.min_change,
+                                                pre_snapshot_cmds=self.args.pre_snapshot_cmd,
+                                                post_snapshot_cmds=self.args.post_snapshot_cmd)
 
             ################# sync
             # if target is specified, we sync the datasets, otherwise we just thin the source. (e.g. snapshot mode)

zfs_autobackup/ZfsDataset.py

@@ -503,7 +503,7 @@ class ZfsDataset:
 
         return self.from_names(names[1:])
 
-    def send_pipe(self, features, prev_snapshot, resume_token, show_progress, raw, send_properties, write_embedded, send_pipes):
+    def send_pipe(self, features, prev_snapshot, resume_token, show_progress, raw, send_properties, write_embedded, send_pipes, zfs_compressed):
         """returns a pipe with zfs send output for this snapshot
 
         resume_token: resume sending from this token. (in that case we don't
@@ -530,7 +530,7 @@ class ZfsDataset:
         if write_embedded and 'embedded_data' in features and "-e" in self.zfs_node.supported_send_options:
             cmd.append("--embed")  # WRITE_EMBEDDED, more compact stream
 
-        if "-c" in self.zfs_node.supported_send_options:
+        if zfs_compressed and "-c" in self.zfs_node.supported_send_options:
             cmd.append("--compressed")  # use compressed WRITE records
 
         # raw? (send over encrypted data in its original encrypted form without decrypting)
@@ -634,7 +634,7 @@ class ZfsDataset:
 
     def transfer_snapshot(self, target_snapshot, features, prev_snapshot, show_progress,
                           filter_properties, set_properties, ignore_recv_exit_code, resume_token,
-                          raw, send_properties, write_embedded, send_pipes, recv_pipes):
+                          raw, send_properties, write_embedded, send_pipes, recv_pipes, zfs_compressed):
         """transfer this snapshot to target_snapshot. specify prev_snapshot for
         incremental transfer
 
@@ -673,12 +673,13 @@ class ZfsDataset:
 
         # do it
         pipe = self.send_pipe(features=features, show_progress=show_progress, prev_snapshot=prev_snapshot,
-                              resume_token=resume_token, raw=raw, send_properties=send_properties, write_embedded=write_embedded, send_pipes=send_pipes)
+                              resume_token=resume_token, raw=raw, send_properties=send_properties, write_embedded=write_embedded, send_pipes=send_pipes, zfs_compressed=zfs_compressed)
         target_snapshot.recv_pipe(pipe, features=features, filter_properties=filter_properties,
                                   set_properties=set_properties, ignore_exit_code=ignore_recv_exit_code, recv_pipes=recv_pipes)
 
     def abort_resume(self):
         """abort current resume state"""
+        self.debug("Aborting resume")
         self.zfs_node.run(["zfs", "recv", "-A", self.name])
 
     def rollback(self):
@@ -901,14 +902,18 @@ class ZfsDataset:
         """
 
         if 'receive_resume_token' in target_dataset.properties:
-            resume_token = target_dataset.properties['receive_resume_token']
+            if start_snapshot==None:
-            # not valid anymore?
+                target_dataset.verbose("Aborting resume, its obsolete.")
-            resume_snapshot = self.get_resume_snapshot(resume_token)
-            if not resume_snapshot or start_snapshot.snapshot_name != resume_snapshot.snapshot_name:
-                target_dataset.verbose("Cant resume, resume token no longer valid.")
                 target_dataset.abort_resume()
             else:
-                return resume_token
+                resume_token = target_dataset.properties['receive_resume_token']
+                # not valid anymore
+                resume_snapshot = self.get_resume_snapshot(resume_token)
+                if not resume_snapshot or start_snapshot.snapshot_name != resume_snapshot.snapshot_name:
+                    target_dataset.verbose("Aborting resume, its no longer valid.")
+                    target_dataset.abort_resume()
+                else:
+                    return resume_token
 
     def _plan_sync(self, target_dataset, also_other_snapshots):
         """plan where to start syncing and what to sync and what to keep
@@ -963,7 +968,7 @@ class ZfsDataset:
 
     def sync_snapshots(self, target_dataset, features, show_progress, filter_properties, set_properties,
                        ignore_recv_exit_code, holds, rollback, decrypt, encrypt, also_other_snapshots,
-                       no_send, destroy_incompatible, send_pipes, recv_pipes):
+                       no_send, destroy_incompatible, send_pipes, recv_pipes, zfs_compressed):
         """sync this dataset's snapshots to target_dataset, while also thinning
         out old snapshots along the way.
 
@@ -1046,7 +1051,7 @@ class ZfsDataset:
                                                   filter_properties=active_filter_properties,
                                                   set_properties=active_set_properties,
                                                   ignore_recv_exit_code=ignore_recv_exit_code,
-                                                  resume_token=resume_token, write_embedded=write_embedded, raw=raw, send_properties=send_properties, send_pipes=send_pipes, recv_pipes=recv_pipes)
+                                                  resume_token=resume_token, write_embedded=write_embedded, raw=raw, send_properties=send_properties, send_pipes=send_pipes, recv_pipes=recv_pipes, zfs_compressed=zfs_compressed)
 
                 resume_token = None
 
@@ -1075,7 +1080,7 @@ class ZfsDataset:
                 source_snapshot.debug("skipped (target doesn't need it)")
                 # was it actually a resume?
                 if resume_token:
-                    target_dataset.debug("aborting resume, since we don't want that snapshot anymore")
+                    target_dataset.verbose("Aborting resume, we dont want that snapshot anymore.")
                     target_dataset.abort_resume()
                     resume_token = None
 

zfs_autobackup/ZfsNode.py

@@ -1,6 +1,7 @@
 # python 2 compatibility
 from __future__ import print_function
 import re
+import shlex
 import subprocess
 import sys
 import time
@@ -161,7 +162,7 @@ class ZfsNode(ExecuteNode):
         """determine uniq new snapshotname"""
         return self.backup_name + "-" + time.strftime("%Y%m%d%H%M%S")
 
-    def consistent_snapshot(self, datasets, snapshot_name, min_changed_bytes):
+    def consistent_snapshot(self, datasets, snapshot_name, min_changed_bytes, pre_snapshot_cmds=[], post_snapshot_cmds=[]):
         """create a consistent (atomic) snapshot of specified datasets, per pool.
         """
 
@@ -191,17 +192,32 @@ class ZfsNode(ExecuteNode):
             self.verbose("No changes anywhere: not creating snapshots.")
             return
 
-        # create consistent snapshot per pool
+        try:
-        for (pool_name, snapshots) in pools.items():
+            for cmd in pre_snapshot_cmds:
-            cmd = ["zfs", "snapshot"]
+                self.verbose("Running pre-snapshot-cmd")
+                self.run(cmd=shlex.split(cmd), readonly=False)
+
+            # create consistent snapshot per pool
+            for (pool_name, snapshots) in pools.items():
+                cmd = ["zfs", "snapshot"]
+
+                cmd.extend(map(lambda snapshot_: str(snapshot_), snapshots))
+
+                self.verbose("Creating snapshots {} in pool {}".format(snapshot_name, pool_name))
+                self.run(cmd, readonly=False)
+
+        finally:
+            for cmd in post_snapshot_cmds:
+                self.verbose("Running post-snapshot-cmd")
+                try:
+                    self.run(cmd=shlex.split(cmd), readonly=False)
+                except Exception as e:
+                    pass
 
-            cmd.extend(map(lambda snapshot_: str(snapshot_), snapshots))
 
-            self.verbose("Creating snapshots {} in pool {}".format(snapshot_name, pool_name))
-            self.run(cmd, readonly=False)
 
     def selected_datasets(self, exclude_received, exclude_paths):
-        """determine filesystems that should be backupped by looking at the special autobackup-property, systemwide
+        """determine filesystems that should be backed up by looking at the special autobackup-property, systemwide
 
            returns: list of ZfsDataset
         """