]>
Commit | Line | Data |
---|---|---|
1 | =============== | |
2 | Ceph Glossary | |
3 | =============== | |
4 | ||
5 | Ceph is growing rapidly. As firms deploy Ceph, the technical terms such as | |
6 | "RADOS", "RBD," "RGW" and so forth require corresponding marketing terms | |
7 | that explain what each component does. The terms in this glossary are | |
8 | intended to complement the existing technical terminology. | |
9 | ||
10 | Sometimes more than one term applies to a definition. Generally, the first | |
11 | term reflects a term consistent with Ceph's marketing, and secondary terms | |
12 | reflect either technical terms or legacy ways of referring to Ceph systems. | |
13 | ||
14 | ||
15 | .. glossary:: | |
16 | ||
17 | Ceph Project | |
18 | The aggregate term for the people, software, mission and infrastructure | |
19 | of Ceph. | |
20 | ||
21 | cephx | |
22 | The Ceph authentication protocol. Cephx operates like Kerberos, but it | |
23 | has no single point of failure. | |
24 | ||
25 | Ceph | |
26 | Ceph Platform | |
27 | All Ceph software, which includes any piece of code hosted at | |
28 | `http://github.com/ceph`_. | |
29 | ||
30 | Ceph System | |
31 | Ceph Stack | |
32 | A collection of two or more components of Ceph. | |
33 | ||
34 | Ceph Node | |
35 | Node | |
36 | Host | |
37 | Any single machine or server in a Ceph System. | |
38 | ||
39 | Ceph Storage Cluster | |
40 | Ceph Object Store | |
41 | RADOS | |
42 | RADOS Cluster | |
43 | Reliable Autonomic Distributed Object Store | |
44 | The core set of storage software which stores the user's data (MON+OSD). | |
45 | ||
46 | Ceph Cluster Map | |
47 | cluster map | |
48 | The set of maps comprising the monitor map, OSD map, PG map, MDS map and | |
49 | CRUSH map. See `Cluster Map`_ for details. | |
50 | ||
51 | Ceph Object Storage | |
52 | The object storage "product", service or capabilities, which consists | |
53 | essentially of a Ceph Storage Cluster and a Ceph Object Gateway. | |
54 | ||
55 | Ceph Object Gateway | |
56 | RADOS Gateway | |
57 | RGW | |
58 | The S3/Swift gateway component of Ceph. | |
59 | ||
60 | Ceph Block Device | |
61 | RBD | |
62 | The block storage component of Ceph. | |
63 | ||
64 | Ceph Block Storage | |
65 | The block storage "product," service or capabilities when used in | |
66 | conjunction with ``librbd``, a hypervisor such as QEMU or Xen, and a | |
67 | hypervisor abstraction layer such as ``libvirt``. | |
68 | ||
69 | Ceph Filesystem | |
70 | CephFS | |
71 | Ceph FS | |
72 | The POSIX filesystem components of Ceph. | |
73 | ||
74 | Cloud Platforms | |
75 | Cloud Stacks | |
76 | Third party cloud provisioning platforms such as OpenStack, CloudStack, | |
77 | OpenNebula, ProxMox, etc. | |
78 | ||
79 | Object Storage Device | |
80 | OSD | |
81 | A physical or logical storage unit (*e.g.*, LUN). | |
82 | Sometimes, Ceph users use the | |
83 | term "OSD" to refer to :term:`Ceph OSD Daemon`, though the | |
84 | proper term is "Ceph OSD". | |
85 | ||
86 | Ceph OSD Daemon | |
87 | Ceph OSD Daemons | |
88 | Ceph OSD | |
89 | The Ceph OSD software, which interacts with a logical | |
90 | disk (:term:`OSD`). Sometimes, Ceph users use the | |
91 | term "OSD" to refer to "Ceph OSD Daemon", though the | |
92 | proper term is "Ceph OSD". | |
93 | ||
94 | OSD id | |
95 | The integer that defines an OSD. It is generated by the monitors as part | |
96 | of the creation of a new OSD. | |
97 | ||
98 | OSD fsid | |
99 | This is a unique identifier used to further improve the uniqueness of an | |
100 | OSD and it is found in the OSD path in a file called ``osd_fsid``. This | |
101 | ``fsid`` term is used interchangeably with ``uuid`` | |
102 | ||
103 | OSD uuid | |
104 | Just like the OSD fsid, this is the OSD unique identifer and is used | |
105 | interchangeably with ``fsid`` | |
106 | ||
107 | bluestore | |
108 | OSD BlueStore is a new back end for OSD daemons (kraken and newer | |
109 | versions). Unlike :term:`filestore` it stores objects directly on the | |
110 | Ceph block devices without any file system interface. | |
111 | ||
112 | filestore | |
113 | A back end for OSD daemons, where a Journal is needed and files are | |
114 | written to the filesystem. | |
115 | ||
116 | Ceph Monitor | |
117 | MON | |
118 | The Ceph monitor software. | |
119 | ||
120 | Ceph Manager | |
121 | MGR | |
122 | The Ceph manager software, which collects all the state from the whole | |
123 | cluster in one place. | |
124 | ||
125 | Ceph Metadata Server | |
126 | MDS | |
127 | The Ceph metadata software. | |
128 | ||
129 | Ceph Clients | |
130 | Ceph Client | |
131 | The collection of Ceph components which can access a Ceph Storage | |
132 | Cluster. These include the Ceph Object Gateway, the Ceph Block Device, | |
133 | the Ceph Filesystem, and their corresponding libraries, kernel modules, | |
134 | and FUSEs. | |
135 | ||
136 | Ceph Kernel Modules | |
137 | The collection of kernel modules which can be used to interact with the | |
138 | Ceph System (e.g,. ``ceph.ko``, ``rbd.ko``). | |
139 | ||
140 | Ceph Client Libraries | |
141 | The collection of libraries that can be used to interact with components | |
142 | of the Ceph System. | |
143 | ||
144 | Ceph Release | |
145 | Any distinct numbered version of Ceph. | |
146 | ||
147 | Ceph Point Release | |
148 | Any ad-hoc release that includes only bug or security fixes. | |
149 | ||
150 | Ceph Interim Release | |
151 | Versions of Ceph that have not yet been put through quality assurance | |
152 | testing, but may contain new features. | |
153 | ||
154 | Ceph Release Candidate | |
155 | A major version of Ceph that has undergone initial quality assurance | |
156 | testing and is ready for beta testers. | |
157 | ||
158 | Ceph Stable Release | |
159 | A major version of Ceph where all features from the preceding interim | |
160 | releases have been put through quality assurance testing successfully. | |
161 | ||
162 | Ceph Test Framework | |
163 | Teuthology | |
164 | The collection of software that performs scripted tests on Ceph. | |
165 | ||
166 | CRUSH | |
167 | Controlled Replication Under Scalable Hashing. It is the algorithm | |
168 | Ceph uses to compute object storage locations. | |
169 | ||
170 | CRUSH rule | |
171 | The CRUSH data placement rule that applies to a particular pool(s). | |
172 | ||
173 | Pool | |
174 | Pools | |
175 | Pools are logical partitions for storing objects. | |
176 | ||
177 | systemd oneshot | |
178 | A systemd ``type`` where a command is defined in ``ExecStart`` which will | |
179 | exit upon completion (it is not intended to daemonize) | |
180 | ||
181 | LVM tags | |
182 | Extensible metadata for LVM volumes and groups. It is used to store | |
183 | Ceph-specific information about devices and its relationship with | |
184 | OSDs. | |
185 | ||
186 | .. _http://github.com/ceph: http://github.com/ceph | |
187 | .. _Cluster Map: ../architecture#cluster-map |