mirror of
https://github.com/ceph/ceph
synced 2024-12-22 11:31:55 +00:00
008698b37c
http://tracker.ceph.com/issues/5834 fixes:#5834 signed-off-by: Baptiste Veuillez--Mainard <baptiste.veuillez--mainard@telecom-bretagne.eu>
150 lines
3.9 KiB
ReStructuredText
150 lines
3.9 KiB
ReStructuredText
==============================================
|
|
ceph-dencoder -- ceph encoder/decoder utility
|
|
==============================================
|
|
|
|
.. program:: ceph-dencoder
|
|
|
|
Synopsis
|
|
========
|
|
|
|
| **ceph-dencoder** [commands...]
|
|
|
|
|
|
Description
|
|
===========
|
|
|
|
**ceph-dencoder** is a utility to encode, decode, and dump ceph data
|
|
structures. It is used for debugging and for testing inter-version
|
|
compatibility.
|
|
|
|
**ceph-dencoder** takes a simple list of commands and performs them
|
|
in order.
|
|
|
|
Commands
|
|
========
|
|
|
|
.. option:: version
|
|
|
|
Print the version string for the **ceph-dencoder** binary.
|
|
|
|
.. option:: import <file>
|
|
|
|
Read a binary blob of encoded data from the given file. It will be
|
|
placed in an in-memory buffer.
|
|
|
|
.. option:: export <file>
|
|
|
|
Write the contents of the current in-memory buffer to the given
|
|
file.
|
|
|
|
.. option:: list_types
|
|
|
|
List the data types known to this build of **ceph-dencoder**.
|
|
|
|
.. option:: type <name>
|
|
|
|
Select the given type for future ``encode`` or ``decode`` operations.
|
|
|
|
.. option:: skip <bytes>
|
|
|
|
Seek <bytes> into the imported file before reading data structure, use
|
|
this with objects that have a preamble/header before the object of interest.
|
|
|
|
.. option:: decode
|
|
|
|
Decode the contents of the in-memory buffer into an instance of the
|
|
previously selected type. If there is an error, report it.
|
|
|
|
.. option:: encode
|
|
|
|
Encode the contents of the in-memory instance of the previously
|
|
selected type to the in-memory buffer.
|
|
|
|
.. option:: dump_json
|
|
|
|
Print a JSON-formatted description of the in-memory object.
|
|
|
|
.. option:: count_tests
|
|
|
|
Print the number of built-in test instances of the previosly
|
|
selected type that **ceph-dencoder** is able to generate.
|
|
|
|
.. option:: select_test <n>
|
|
|
|
Select the given build-in test instance as a the in-memory instance
|
|
of the type.
|
|
|
|
.. option:: get_features
|
|
|
|
Print the decimal value of the feature set supported by this version
|
|
of **ceph-dencoder**. Each bit represents a feature. These correspond to
|
|
CEPH_FEATURE_* defines in src/include/ceph_features.h.
|
|
|
|
.. option:: set_features <f>
|
|
|
|
Set the feature bits provided to ``encode`` to *f*. This allows
|
|
you to encode objects such that they can be understood by old
|
|
versions of the software (for those types that support it).
|
|
|
|
Example
|
|
=======
|
|
|
|
Say you want to examine an attribute on an object stored by ``ceph-osd``. You can do this:
|
|
|
|
::
|
|
|
|
$ cd /mnt/osd.12/current/2.b_head
|
|
$ attr -l foo_bar_head_EFE6384B
|
|
Attribute "ceph.snapset" has a 31 byte value for foo_bar_head_EFE6384B
|
|
Attribute "ceph._" has a 195 byte value for foo_bar_head_EFE6384B
|
|
$ attr foo_bar_head_EFE6384B -g ceph._ -q > /tmp/a
|
|
$ ceph-dencoder type object_info_t import /tmp/a decode dump_json
|
|
{ "oid": { "oid": "foo",
|
|
"key": "bar",
|
|
"snapid": -2,
|
|
"hash": 4024842315,
|
|
"max": 0},
|
|
"locator": { "pool": 2,
|
|
"preferred": -1,
|
|
"key": "bar"},
|
|
"category": "",
|
|
"version": "9'1",
|
|
"prior_version": "0'0",
|
|
"last_reqid": "client.4116.0:1",
|
|
"size": 1681,
|
|
"mtime": "2012-02-21 08:58:23.666639",
|
|
"lost": 0,
|
|
"wrlock_by": "unknown.0.0:0",
|
|
"snaps": [],
|
|
"truncate_seq": 0,
|
|
"truncate_size": 0,
|
|
"watchers": {}}
|
|
|
|
Alternatively, perhaps you wish to dump an internal CephFS metadata object, you might
|
|
do that like this:
|
|
|
|
::
|
|
|
|
$ rados -p metadata get mds_snaptable mds_snaptable.bin
|
|
$ ceph-dencoder type SnapServer skip 8 import mds_snaptable.bin decode dump_json
|
|
{ "snapserver": { "last_snap": 1,
|
|
"pending_noop": [],
|
|
"snaps": [],
|
|
"need_to_purge": {},
|
|
"pending_create": [],
|
|
"pending_destroy": []}}
|
|
|
|
|
|
Availability
|
|
============
|
|
|
|
**ceph-dencoder** is part of Ceph, a massively scalable, open-source, distributed storage system. Please
|
|
refer to the Ceph documentation at http://ceph.com/docs for more
|
|
information.
|
|
|
|
|
|
See also
|
|
========
|
|
|
|
:doc:`ceph <ceph>`\(8)
|