Commit Graph

5 Commits

Author SHA1 Message Date
Chris Dunlap
aded9a6814 Cleanup ZEDLETs
This commit factors out several common ZEDLET code blocks into
zed-functions.sh.  This shortens the length of the scripts, thereby
(hopefully) making them easier to understand and maintain.

In addition, this commit revamps the coding style used by the
scripts to be more consistent and (again, hopefully) maintainable.
It now mostly follows the Google Shell Style Guide.  I've tried to
assimilate the following resources:

  Google Shell Style Guide
  https://google-styleguide.googlecode.com/svn/trunk/shell.xml

  Dash as /bin/sh
  https://wiki.ubuntu.com/DashAsBinSh

  Filenames and Pathnames in Shell: How to do it Correctly
  http://www.dwheeler.com/essays/filenames-in-shell.html

  Common shell script mistakes
  http://www.pixelbeat.org/programming/shell_script_mistakes.html

Finally, this commit updates the exit codes used by the ZEDLETs to be
more consistent with one another.

All scripts run cleanly through ShellCheck <http://www.shellcheck.net/>.
All scripts have been tested on bash and dash.

Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
2015-04-27 12:08:01 -07:00
Chris Dunlap
de6d197683 Fix io-spare.sh to work with disk vdevs
The "zpool status" output shows the full pathname for file-type vdevs,
but only the basename component for disk-type vdevs.  In commit
bee6665, the "basename" command was dropped from altering the vdev
name used when searching the "zpool status" output.  Consequently,
hot-disk sparing for disk vdevs broke since "zpool status" output
was now being searched for the full pathname to the disk vdev.

Parsing the "zpool status" output in this manner is rather brittle.
It would be preferable to search for the vdev based on its guid.
But until that happens, this commit adds back the "basename" command
to fix the vdev name breakage.

Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3310
2015-04-17 14:21:26 -07:00
Chris Dunlap
dcca723ace Refer to ZED's scripts as ZEDLETs
The executables invoked by the ZED in response to a given zevent
have been generically referred to as "scripts".  By convention,
these scripts have aimed to be /bin/sh compatible for reasons of
portability and comprehensibility.  However, the ZED only requires
they be executable and (ideally) capable of reading environment
variables.  As such, these scripts are now referred to as ZEDLETs
(ZFS Event Daemon Linkage for Executable Tasks).

Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2735
2014-09-25 13:54:17 -07:00
Chris Dunlap
bee6665b88 Fix zed io-spare.sh dash incompatibility
The zed's io-spare.sh script defines a vdev_status() function to query
the 'zpool status' output for obtaining the status of a specified vdev.
This function contains a small awk script that uses a parameter
expansion (${parameter/pattern/string}) supported in bash but not
in dash.  Under dash, this fails with a "Bad substitution" error.

This commit replaces the awk script with a (hopefully more portable)
sed script that has been tested under both bash and dash.

Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2536
2014-09-23 15:32:30 -07:00
Brian Behlendorf
904ea2763e Add automatic hot spare functionality
When a vdev starts getting I/O or checksum errors it is now
possible to automatically rebuild to a hot spare device.

To cleanly support this functionality in a shell script some
additional information was added to all zevent ereports which
include a vdev.  This covers both io and checksum zevents but
may be used but other scripts.

In the Illumos FMA solution the same information is required
but it is retrieved through the libzfs library interface.
Specifically the following members were added:

  vdev_spare_paths  - List of vdev paths for all hot spares.
  vdev_spare_guids  - List of vdev guids for all hot spares.
  vdev_read_errors  - Read errors for the problematic vdev
  vdev_write_errors - Write errors for the problematic vdev
  vdev_cksum_errors - Checksum errors for the problematic vdev.

By default the required hot spare scripts are installed but this
functionality is disabled.  To enable hot sparing uncomment the
ZED_SPARE_ON_IO_ERRORS and ZED_SPARE_ON_CHECKSUM_ERRORS in the
/etc/zfs/zed.d/zed.rc configuration file.

These scripts do no add support for the autoexpand property. At
a minimum this requires adding a new udev rule to detect when
a new device is added to the system.  It also requires that the
autoexpand policy be ported from Illumos, see:

  https://github.com/illumos/illumos-gate/blob/master/usr/src/cmd/syseventd/modules/zfs_mod/zfs_mod.c

Support for detecting the correct name of a vdev when it's not
a whole disk was added by Turbo Fredriksson.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Issue #2
2014-04-02 13:10:08 -07:00