mirror_zfs/tests
Pavel Zakharov 6cb8e5306d OpenZFS 9075 - Improve ZFS pool import/load process and corrupted pool recovery
Some work has been done lately to improve the debugability of the ZFS pool
load (and import) process. This includes:

	7638 Refactor spa_load_impl into several functions
	8961 SPA load/import should tell us why it failed
	7277 zdb should be able to print zfs_dbgmsg's

To iterate on top of that, there's a few changes that were made to make the
import process more resilient and crash free. One of the first tasks during the
pool load process is to parse a config provided from userland that describes
what devices the pool is composed of. A vdev tree is generated from that config,
and then all the vdevs are opened.

The Meta Object Set (MOS) of the pool is accessed, and several metadata objects
that are necessary to load the pool are read. The exact configuration of the
pool is also stored inside the MOS. Since the configuration provided from
userland is external and might not accurately describe the vdev tree
of the pool at the txg that is being loaded, it cannot be relied upon to safely
operate the pool. For that reason, the configuration in the MOS is read early
on. In the past, the two configurations were compared together and if there was
a mismatch then the load process was aborted and an error was returned.

The latter was a good way to ensure a pool does not get corrupted, however it
made the pool load process needlessly fragile in cases where the vdev
configuration changed or the userland configuration was outdated. Since the MOS
is stored in 3 copies, the configuration provided by userland doesn't have to be
perfect in order to read its contents. Hence, a new approach has been adopted:
The pool is first opened with the untrusted userland configuration just so that
the real configuration can be read from the MOS. The trusted MOS configuration
is then used to generate a new vdev tree and the pool is re-opened.

When the pool is opened with an untrusted configuration, writes are disabled
to avoid accidentally damaging it. During reads, some sanity checks are
performed on block pointers to see if each DVA points to a known vdev;
when the configuration is untrusted, instead of panicking the system if those
checks fail we simply avoid issuing reads to the invalid DVAs.

This new two-step pool load process now allows rewinding pools accross
vdev tree changes such as device replacement, addition, etc. Loading a pool
from an external config file in a clustering environment also becomes much
safer now since the pool will import even if the config is outdated and didn't,
for instance, register a recent device addition.

With this code in place, it became relatively easy to implement a
long-sought-after feature: the ability to import a pool with missing top level
(i.e. non-redundant) devices. Note that since this almost guarantees some loss
of data, this feature is for now restricted to a read-only import.

Porting notes (ZTS):
* Fix 'make dist' target in zpool_import

* The maximum path length allowed by tar is 99 characters.  Several
  of the new test cases exceeded this limit resulting in them not
  being included in the tarball.  Shorten the names slightly.

* Set/get tunables using accessor functions.

* Get last synced txg via the "zfs_txg_history" mechanism.

* Clear zinject handlers in cleanup for import_cache_device_replaced
  and import_rewind_device_replaced in order that the zpool can be
  exported if there is an error.

* Increase FILESIZE to 8G in zfs-test.sh to allow for a larger
  ext4 file system to be created on ZFS_DISK2.  Also, there's
  no need to partition ZFS_DISK2 at all.  The partitioning had
  already been disabled for multipath devices.  Among other things,
  the partitioning steals some space from the ext4 file system,
  makes it difficult to accurately calculate the paramters to
  parted and can make some of the tests fail.

* Increase FS_SIZE and FILE_SIZE in the zpool_import test
  configuration now that FILESIZE is larger.

* Write more data in order that device evacuation take lonnger in
  a couple tests.

* Use mkdir -p to avoid errors when the directory already exists.

* Remove use of sudo in import_rewind_config_changed.

Authored by: Pavel Zakharov <pavel.zakharov@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Andrew Stormont <andyjstormont@gmail.com>
Approved by: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Ported-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Tim Chase <tim@chase2k.com>

OpenZFS-issue: https://illumos.org/issues/9075
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/619c0123
Closes #7459
2018-05-08 21:35:27 -07:00
..
runfiles OpenZFS 9075 - Improve ZFS pool import/load process and corrupted pool recovery 2018-05-08 21:35:27 -07:00
test-runner Clean up (k)shlib and cfg file shebangs 2018-04-08 19:37:22 -07:00
zfs-tests OpenZFS 9075 - Improve ZFS pool import/load process and corrupted pool recovery 2018-05-08 21:35:27 -07:00
Makefile.am Add the ZFS Test Suite 2016-03-16 13:46:16 -07:00
README.md ZTS: minor typo and old default values 2017-07-03 14:21:12 -07:00

ZFS Test Suite README

  1. Building and installing the ZFS Test Suite

The ZFS Test Suite runs under the test-runner framework. This framework is built along side the standard ZFS utilities and is included as part of zfs-test package. The zfs-test package can be built from source as follows:

$ ./configure
$ make pkg-utils

The resulting packages can be installed using the rpm or dpkg command as appropriate for your distributions. Alternately, if you have installed ZFS from a distributions repository (not from source) the zfs-test package may be provided for your distribution.

- Installed from source
$ rpm -ivh ./zfs-test*.rpm, or
$ dpkg -i ./zfs-test*.deb,

- Installed from package repository
$ yum install zfs-test
$ apt-get install zfs-test
  1. Running the ZFS Test Suite

The pre-requisites for running the ZFS Test Suite are:

  • Three scratch disks
    • Specify the disks you wish to use in the $DISKS variable, as a space delimited list like this: DISKS='vdb vdc vdd'. By default the zfs-tests.sh sciprt will construct three loopback devices to be used for testing: DISKS='loop0 loop1 loop2'.
  • A non-root user with a full set of basic privileges and the ability to sudo(8) to root without a password to run the test.
  • Specify any pools you wish to preserve as a space delimited list in the $KEEP variable. All pools detected at the start of testing are added automatically.
  • The ZFS Test Suite will add users and groups to test machine to verify functionality. Therefore it is strongly advised that a dedicated test machine, which can be a VM, be used for testing.

Once the pre-requisites are satisfied simply run the zfs-tests.sh script:

$ /usr/share/zfs/zfs-tests.sh

Alternately, the zfs-tests.sh script can be run from the source tree to allow developers to rapidly validate their work. In this mode the ZFS utilities and modules from the source tree will be used (rather than those installed on the system). In order to avoid certain types of failures you will need to ensure the ZFS udev rules are installed. This can be done manually or by ensuring some version of ZFS is installed on the system.

$ ./scripts/zfs-tests.sh

The following zfs-tests.sh options are supported:

-v          Verbose zfs-tests.sh output When specified additional
            information describing the test environment will be logged
            prior to invoking test-runner.  This includes the runfile
            being used, the DISKS targeted, pools to keep, etc.

-q          Quiet test-runner output.  When specified it is passed to
            test-runner(1) which causes output to be written to the
            console only for tests that do not pass and the results
            summary.

-x          Remove all testpools, dm, lo, and files (unsafe).  When
            specified the script will attempt to remove any leftover
            configuration from a previous test run.  This includes
            destroying any pools named testpool, unused DM devices,
            and loopback devices backed by file-vdevs.  This operation
            can be DANGEROUS because it is possible that the script
            will mistakenly remove a resource not related to the testing.

-k          Disable cleanup after test failure.  When specified the
            zfs-tests.sh script will not perform any additional cleanup
            when test-runner exists.  This is useful when the results of
            a specific test need to be preserved for further analysis.

-f          Use sparse files directly instread of loopback devices for
            the testing.  When running in this mode certain tests will
            be skipped which depend on real block devices.

-d DIR      Create sparse files for vdevs in the DIR directory.  By
            default these files are created under /var/tmp/.

-s SIZE     Use vdevs of SIZE (default: 4G)

-r RUNFILE  Run tests in RUNFILE (default: linux.run)

The ZFS Test Suite allows the user to specify a subset of the tests via a runfile. The format of the runfile is explained in test-runner(1), and the files that zfs-tests.sh uses are available for reference under /usr/share/zfs/runfiles. To specify a custom runfile, use the -r option:

$ /usr/share/zfs/zfs-tests.sh -r my_tests.run
  1. Test results

While the ZFS Test Suite is running, one informational line is printed at the end of each test, and a results summary is printed at the end of the run. The results summary includes the location of the complete logs, which is logged in the form /var/tmp/test_results/[ISO 8601 date]. A normal test run launched with the zfs-tests.sh wrapper script will look something like this:

$ /usr/share/zfs/zfs-tests.sh -v -d /mnt

--- Configuration --- Runfile: /usr/share/zfs/runfiles/linux.run STF_TOOLS: /usr/share/zfs/test-runner STF_SUITE: /usr/share/zfs/zfs-tests FILEDIR: /mnt FILES: /mnt/file-vdev0 /mnt/file-vdev1 /mnt/file-vdev2 LOOPBACKS: /dev/loop0 /dev/loop1 /dev/loop2 DISKS: loop0 loop1 loop2 NUM_DISKS: 3 FILESIZE: 4G Keep pool(s): rpool

/usr/share/zfs/test-runner/bin/test-runner.py -c
/usr/share/zfs/runfiles/linux.run -i /usr/share/zfs/zfs-tests Test: .../tests/functional/acl/posix/setup (run as root) [00:00] [PASS] ...470 additional tests... Test: .../tests/functional/zvol/zvol_cli/cleanup (run as root) [00:00] [PASS]

Results Summary PASS 472

Running Time: 00:45:09 Percent passed: 100.0% Log directory: /var/tmp/test_results/20160316T181651