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80c0adcb | 1 | [[chapter_pveceph]] |
0840a663 | 2 | ifdef::manvolnum[] |
b2f242ab DM |
3 | pveceph(1) |
4 | ========== | |
404a158e | 5 | :pve-toplevel: |
0840a663 DM |
6 | |
7 | NAME | |
8 | ---- | |
9 | ||
21394e70 | 10 | pveceph - Manage Ceph Services on Proxmox VE Nodes |
0840a663 | 11 | |
49a5e11c | 12 | SYNOPSIS |
0840a663 DM |
13 | -------- |
14 | ||
15 | include::pveceph.1-synopsis.adoc[] | |
16 | ||
17 | DESCRIPTION | |
18 | ----------- | |
19 | endif::manvolnum[] | |
0840a663 | 20 | ifndef::manvolnum[] |
4bfe3e35 TL |
21 | Deploy Hyper-Converged Ceph Cluster |
22 | =================================== | |
49d3ad91 | 23 | :pve-toplevel: |
0840a663 DM |
24 | endif::manvolnum[] |
25 | ||
1ff5e4e8 | 26 | [thumbnail="screenshot/gui-ceph-status.png"] |
8997dd6e | 27 | |
a474ca1f AA |
28 | {pve} unifies your compute and storage systems, i.e. you can use the same |
29 | physical nodes within a cluster for both computing (processing VMs and | |
30 | containers) and replicated storage. The traditional silos of compute and | |
31 | storage resources can be wrapped up into a single hyper-converged appliance. | |
32 | Separate storage networks (SANs) and connections via network attached storages | |
33 | (NAS) disappear. With the integration of Ceph, an open source software-defined | |
34 | storage platform, {pve} has the ability to run and manage Ceph storage directly | |
35 | on the hypervisor nodes. | |
c994e4e5 DM |
36 | |
37 | Ceph is a distributed object store and file system designed to provide | |
1d54c3b4 AA |
38 | excellent performance, reliability and scalability. |
39 | ||
04ba9b24 TL |
40 | .Some advantages of Ceph on {pve} are: |
41 | - Easy setup and management with CLI and GUI support | |
a474ca1f AA |
42 | - Thin provisioning |
43 | - Snapshots support | |
44 | - Self healing | |
a474ca1f AA |
45 | - Scalable to the exabyte level |
46 | - Setup pools with different performance and redundancy characteristics | |
47 | - Data is replicated, making it fault tolerant | |
48 | - Runs on economical commodity hardware | |
49 | - No need for hardware RAID controllers | |
a474ca1f AA |
50 | - Open source |
51 | ||
1d54c3b4 AA |
52 | For small to mid sized deployments, it is possible to install a Ceph server for |
53 | RADOS Block Devices (RBD) directly on your {pve} cluster nodes, see | |
c994e4e5 DM |
54 | xref:ceph_rados_block_devices[Ceph RADOS Block Devices (RBD)]. Recent |
55 | hardware has plenty of CPU power and RAM, so running storage services | |
56 | and VMs on the same node is possible. | |
21394e70 DM |
57 | |
58 | To simplify management, we provide 'pveceph' - a tool to install and | |
59 | manage {ceph} services on {pve} nodes. | |
60 | ||
2798d126 | 61 | .Ceph consists of a couple of Daemons footnote:[Ceph intro https://docs.ceph.com/docs/{ceph_codename}/start/intro/], for use as a RBD storage: |
1d54c3b4 AA |
62 | - Ceph Monitor (ceph-mon) |
63 | - Ceph Manager (ceph-mgr) | |
64 | - Ceph OSD (ceph-osd; Object Storage Daemon) | |
65 | ||
477fbcfb | 66 | TIP: We highly recommend to get familiar with Ceph's architecture |
2798d126 | 67 | footnote:[Ceph architecture https://docs.ceph.com/docs/{ceph_codename}/architecture/] |
477fbcfb | 68 | and vocabulary |
2798d126 | 69 | footnote:[Ceph glossary https://docs.ceph.com/docs/{ceph_codename}/glossary]. |
1d54c3b4 | 70 | |
21394e70 DM |
71 | |
72 | Precondition | |
73 | ------------ | |
74 | ||
76f6eca4 AA |
75 | To build a hyper-converged Proxmox + Ceph Cluster there should be at least |
76 | three (preferably) identical servers for the setup. | |
21394e70 DM |
77 | |
78 | Check also the recommendations from | |
2798d126 | 79 | https://docs.ceph.com/docs/{ceph_codename}/start/hardware-recommendations/[Ceph's website]. |
21394e70 | 80 | |
76f6eca4 | 81 | .CPU |
2f19a6b0 TL |
82 | Higher CPU core frequency reduce latency and should be preferred. As a simple |
83 | rule of thumb, you should assign a CPU core (or thread) to each Ceph service to | |
84 | provide enough resources for stable and durable Ceph performance. | |
76f6eca4 AA |
85 | |
86 | .Memory | |
87 | Especially in a hyper-converged setup, the memory consumption needs to be | |
2f19a6b0 TL |
88 | carefully monitored. In addition to the intended workload from virtual machines |
89 | and container, Ceph needs enough memory available to provide good and stable | |
90 | performance. As a rule of thumb, for roughly 1 TiB of data, 1 GiB of memory | |
91 | will be used by an OSD. OSD caching will use additional memory. | |
76f6eca4 AA |
92 | |
93 | .Network | |
94 | We recommend a network bandwidth of at least 10 GbE or more, which is used | |
95 | exclusively for Ceph. A meshed network setup | |
96 | footnote:[Full Mesh Network for Ceph {webwiki-url}Full_Mesh_Network_for_Ceph_Server] | |
97 | is also an option if there are no 10 GbE switches available. | |
98 | ||
2f19a6b0 TL |
99 | The volume of traffic, especially during recovery, will interfere with other |
100 | services on the same network and may even break the {pve} cluster stack. | |
76f6eca4 AA |
101 | |
102 | Further, estimate your bandwidth needs. While one HDD might not saturate a 1 Gb | |
2f19a6b0 TL |
103 | link, multiple HDD OSDs per node can, and modern NVMe SSDs will even saturate |
104 | 10 Gbps of bandwidth quickly. Deploying a network capable of even more bandwith | |
105 | will ensure that it isn't your bottleneck and won't be anytime soon, 25, 40 or | |
106 | even 100 GBps are possible. | |
76f6eca4 AA |
107 | |
108 | .Disks | |
109 | When planning the size of your Ceph cluster, it is important to take the | |
110 | recovery time into consideration. Especially with small clusters, the recovery | |
111 | might take long. It is recommended that you use SSDs instead of HDDs in small | |
112 | setups to reduce recovery time, minimizing the likelihood of a subsequent | |
113 | failure event during recovery. | |
114 | ||
2f19a6b0 | 115 | In general SSDs will provide more IOPs than spinning disks. This fact and the |
76f6eca4 | 116 | higher cost may make a xref:pve_ceph_device_classes[class based] separation of |
2f19a6b0 | 117 | pools appealing. Another possibility to speedup OSDs is to use a faster disk |
352c803f TL |
118 | as journal or DB/**W**rite-**A**head-**L**og device, see |
119 | xref:pve_ceph_osds[creating Ceph OSDs]. If a faster disk is used for multiple | |
120 | OSDs, a proper balance between OSD and WAL / DB (or journal) disk must be | |
121 | selected, otherwise the faster disk becomes the bottleneck for all linked OSDs. | |
76f6eca4 AA |
122 | |
123 | Aside from the disk type, Ceph best performs with an even sized and distributed | |
2f19a6b0 TL |
124 | amount of disks per node. For example, 4 x 500 GB disks with in each node is |
125 | better than a mixed setup with a single 1 TB and three 250 GB disk. | |
126 | ||
127 | One also need to balance OSD count and single OSD capacity. More capacity | |
128 | allows to increase storage density, but it also means that a single OSD | |
129 | failure forces ceph to recover more data at once. | |
76f6eca4 | 130 | |
a474ca1f | 131 | .Avoid RAID |
86be506d | 132 | As Ceph handles data object redundancy and multiple parallel writes to disks |
c78756be | 133 | (OSDs) on its own, using a RAID controller normally doesn’t improve |
86be506d TL |
134 | performance or availability. On the contrary, Ceph is designed to handle whole |
135 | disks on it's own, without any abstraction in between. RAID controller are not | |
136 | designed for the Ceph use case and may complicate things and sometimes even | |
137 | reduce performance, as their write and caching algorithms may interfere with | |
138 | the ones from Ceph. | |
a474ca1f AA |
139 | |
140 | WARNING: Avoid RAID controller, use host bus adapter (HBA) instead. | |
141 | ||
76f6eca4 | 142 | NOTE: Above recommendations should be seen as a rough guidance for choosing |
2f19a6b0 TL |
143 | hardware. Therefore, it is still essential to adapt it to your specific needs, |
144 | test your setup and monitor health and performance continuously. | |
76f6eca4 | 145 | |
2394c306 TM |
146 | [[pve_ceph_install_wizard]] |
147 | Initial Ceph installation & configuration | |
148 | ----------------------------------------- | |
149 | ||
150 | [thumbnail="screenshot/gui-node-ceph-install.png"] | |
151 | ||
152 | With {pve} you have the benefit of an easy to use installation wizard | |
153 | for Ceph. Click on one of your cluster nodes and navigate to the Ceph | |
6a711e64 TL |
154 | section in the menu tree. If Ceph is not already installed you will be |
155 | offered to do so now. | |
2394c306 TM |
156 | |
157 | The wizard is divided into different sections, where each needs to be | |
6a711e64 TL |
158 | finished successfully in order to use Ceph. After starting the installation |
159 | the wizard will download and install all required packages from {pve}'s ceph | |
160 | repository. | |
2394c306 TM |
161 | |
162 | After finishing the first step, you will need to create a configuration. | |
6a711e64 TL |
163 | This step is only needed once per cluster, as this configuration is distributed |
164 | automatically to all remaining cluster members through {pve}'s clustered | |
165 | xref:chapter_pmxcfs[configuration file system (pmxcfs)]. | |
2394c306 TM |
166 | |
167 | The configuration step includes the following settings: | |
168 | ||
169 | * *Public Network:* You should setup a dedicated network for Ceph, this | |
170 | setting is required. Separating your Ceph traffic is highly recommended, | |
6a711e64 TL |
171 | because it could lead to troubles with other latency dependent services, |
172 | e.g., cluster communication may decrease Ceph's performance, if not done. | |
2394c306 TM |
173 | |
174 | [thumbnail="screenshot/gui-node-ceph-install-wizard-step2.png"] | |
175 | ||
176 | * *Cluster Network:* As an optional step you can go even further and | |
177 | separate the xref:pve_ceph_osds[OSD] replication & heartbeat traffic | |
178 | as well. This will relieve the public network and could lead to | |
179 | significant performance improvements especially in big clusters. | |
180 | ||
181 | You have two more options which are considered advanced and therefore | |
182 | should only changed if you are an expert. | |
183 | ||
184 | * *Number of replicas*: Defines the how often a object is replicated | |
185 | * *Minimum replicas*: Defines the minimum number of required replicas | |
6a711e64 | 186 | for I/O to be marked as complete. |
2394c306 | 187 | |
6a711e64 | 188 | Additionally you need to choose your first monitor node, this is required. |
2394c306 TM |
189 | |
190 | That's it, you should see a success page as the last step with further | |
191 | instructions on how to go on. You are now prepared to start using Ceph, | |
192 | even though you will need to create additional xref:pve_ceph_monitors[monitors], | |
193 | create some xref:pve_ceph_osds[OSDs] and at least one xref:pve_ceph_pools[pool]. | |
194 | ||
195 | The rest of this chapter will guide you on how to get the most out of | |
196 | your {pve} based Ceph setup, this will include aforementioned and | |
197 | more like xref:pveceph_fs[CephFS] which is a very handy addition to your | |
198 | new Ceph cluster. | |
21394e70 | 199 | |
58f95dd7 | 200 | [[pve_ceph_install]] |
21394e70 DM |
201 | Installation of Ceph Packages |
202 | ----------------------------- | |
2394c306 TM |
203 | Use {pve} Ceph installation wizard (recommended) or run the following |
204 | command on each node: | |
21394e70 DM |
205 | |
206 | [source,bash] | |
207 | ---- | |
19920184 | 208 | pveceph install |
21394e70 DM |
209 | ---- |
210 | ||
211 | This sets up an `apt` package repository in | |
212 | `/etc/apt/sources.list.d/ceph.list` and installs the required software. | |
213 | ||
214 | ||
b3338e29 AA |
215 | Create initial Ceph configuration |
216 | --------------------------------- | |
21394e70 | 217 | |
1ff5e4e8 | 218 | [thumbnail="screenshot/gui-ceph-config.png"] |
8997dd6e | 219 | |
2394c306 TM |
220 | Use the {pve} Ceph installation wizard (recommended) or run the |
221 | following command on one node: | |
21394e70 DM |
222 | |
223 | [source,bash] | |
224 | ---- | |
225 | pveceph init --network 10.10.10.0/24 | |
226 | ---- | |
227 | ||
2394c306 TM |
228 | This creates an initial configuration at `/etc/pve/ceph.conf` with a |
229 | dedicated network for ceph. That file is automatically distributed to | |
230 | all {pve} nodes by using xref:chapter_pmxcfs[pmxcfs]. The command also | |
231 | creates a symbolic link from `/etc/ceph/ceph.conf` pointing to that file. | |
232 | So you can simply run Ceph commands without the need to specify a | |
233 | configuration file. | |
21394e70 DM |
234 | |
235 | ||
d9a27ee1 | 236 | [[pve_ceph_monitors]] |
b3338e29 AA |
237 | Ceph Monitor |
238 | ----------- | |
1d54c3b4 | 239 | The Ceph Monitor (MON) |
2798d126 | 240 | footnote:[Ceph Monitor https://docs.ceph.com/docs/{ceph_codename}/start/intro/] |
a474ca1f | 241 | maintains a master copy of the cluster map. For high availability you need to |
2394c306 | 242 | have at least 3 monitors. One monitor will already be installed if you |
620d6725 | 243 | used the installation wizard. You won't need more than 3 monitors as long |
2394c306 TM |
244 | as your cluster is small to midsize, only really large clusters will |
245 | need more than that. | |
1d54c3b4 | 246 | |
b3338e29 | 247 | |
c998bdf2 | 248 | [[pveceph_create_mon]] |
b3338e29 AA |
249 | Create Monitors |
250 | ~~~~~~~~~~~~~~~ | |
251 | ||
252 | [thumbnail="screenshot/gui-ceph-monitor.png"] | |
253 | ||
1d54c3b4 AA |
254 | On each node where you want to place a monitor (three monitors are recommended), |
255 | create it by using the 'Ceph -> Monitor' tab in the GUI or run. | |
21394e70 DM |
256 | |
257 | ||
258 | [source,bash] | |
259 | ---- | |
d1fdb121 | 260 | pveceph mon create |
21394e70 DM |
261 | ---- |
262 | ||
c998bdf2 | 263 | [[pveceph_destroy_mon]] |
b3338e29 AA |
264 | Destroy Monitors |
265 | ~~~~~~~~~~~~~~~~ | |
0e38a564 AA |
266 | |
267 | To remove a Ceph Monitor via the GUI first select a node in the tree view and | |
268 | go to the **Ceph -> Monitor** panel. Select the MON and click the **Destroy** | |
269 | button. | |
270 | ||
271 | To remove a Ceph Monitor via the CLI first connect to the node on which the MON | |
272 | is running. Then execute the following command: | |
273 | [source,bash] | |
274 | ---- | |
275 | pveceph mon destroy | |
276 | ---- | |
277 | ||
278 | NOTE: At least three Monitors are needed for quorum. | |
279 | ||
280 | ||
1d54c3b4 | 281 | [[pve_ceph_manager]] |
b3338e29 AA |
282 | Ceph Manager |
283 | ------------ | |
284 | The Manager daemon runs alongside the monitors. It provides an interface to | |
285 | monitor the cluster. Since the Ceph luminous release at least one ceph-mgr | |
2798d126 | 286 | footnote:[Ceph Manager https://docs.ceph.com/docs/{ceph_codename}/mgr/] daemon is |
b3338e29 AA |
287 | required. |
288 | ||
55d634e6 | 289 | [[pveceph_create_mgr]] |
b3338e29 AA |
290 | Create Manager |
291 | ~~~~~~~~~~~~~~ | |
1d54c3b4 | 292 | |
b3338e29 | 293 | Multiple Managers can be installed, but at any time only one Manager is active. |
1d54c3b4 | 294 | |
1d54c3b4 AA |
295 | [source,bash] |
296 | ---- | |
d1fdb121 | 297 | pveceph mgr create |
1d54c3b4 AA |
298 | ---- |
299 | ||
c1f38fe3 AA |
300 | NOTE: It is recommended to install the Ceph Manager on the monitor nodes. For |
301 | high availability install more then one manager. | |
302 | ||
21394e70 | 303 | |
c998bdf2 | 304 | [[pveceph_destroy_mgr]] |
b3338e29 AA |
305 | Destroy Manager |
306 | ~~~~~~~~~~~~~~~ | |
549350fe AA |
307 | |
308 | To remove a Ceph Manager via the GUI first select a node in the tree view and | |
309 | go to the **Ceph -> Monitor** panel. Select the Manager and click the | |
310 | **Destroy** button. | |
311 | ||
312 | To remove a Ceph Monitor via the CLI first connect to the node on which the | |
313 | Manager is running. Then execute the following command: | |
314 | [source,bash] | |
315 | ---- | |
316 | pveceph mgr destroy | |
317 | ---- | |
318 | ||
319 | NOTE: A Ceph cluster can function without a Manager, but certain functions like | |
320 | the cluster status or usage require a running Manager. | |
321 | ||
322 | ||
d9a27ee1 | 323 | [[pve_ceph_osds]] |
b3338e29 AA |
324 | Ceph OSDs |
325 | --------- | |
326 | Ceph **O**bject **S**torage **D**aemons are storing objects for Ceph over the | |
327 | network. It is recommended to use one OSD per physical disk. | |
328 | ||
329 | NOTE: By default an object is 4 MiB in size. | |
330 | ||
081cb761 | 331 | [[pve_ceph_osd_create]] |
b3338e29 AA |
332 | Create OSDs |
333 | ~~~~~~~~~~~ | |
21394e70 | 334 | |
1ff5e4e8 | 335 | [thumbnail="screenshot/gui-ceph-osd-status.png"] |
8997dd6e | 336 | |
21394e70 DM |
337 | via GUI or via CLI as follows: |
338 | ||
339 | [source,bash] | |
340 | ---- | |
d1fdb121 | 341 | pveceph osd create /dev/sd[X] |
21394e70 DM |
342 | ---- |
343 | ||
b3338e29 AA |
344 | TIP: We recommend a Ceph cluster size, starting with 12 OSDs, distributed |
345 | evenly among your, at least three nodes (4 OSDs on each node). | |
1d54c3b4 | 346 | |
a474ca1f | 347 | If the disk was used before (eg. ZFS/RAID/OSD), to remove partition table, boot |
9bddef40 | 348 | sector and any OSD leftover the following command should be sufficient. |
a474ca1f AA |
349 | |
350 | [source,bash] | |
351 | ---- | |
9bddef40 | 352 | ceph-volume lvm zap /dev/sd[X] --destroy |
a474ca1f AA |
353 | ---- |
354 | ||
9bddef40 | 355 | WARNING: The above command will destroy data on the disk! |
1d54c3b4 | 356 | |
b3338e29 | 357 | .Ceph Bluestore |
21394e70 | 358 | |
1d54c3b4 AA |
359 | Starting with the Ceph Kraken release, a new Ceph OSD storage type was |
360 | introduced, the so called Bluestore | |
2798d126 | 361 | footnote:[Ceph Bluestore https://ceph.com/community/new-luminous-bluestore/]. |
9bddef40 | 362 | This is the default when creating OSDs since Ceph Luminous. |
21394e70 DM |
363 | |
364 | [source,bash] | |
365 | ---- | |
d1fdb121 | 366 | pveceph osd create /dev/sd[X] |
1d54c3b4 AA |
367 | ---- |
368 | ||
1e834cb2 | 369 | .Block.db and block.wal |
1d54c3b4 AA |
370 | |
371 | If you want to use a separate DB/WAL device for your OSDs, you can specify it | |
b3338e29 AA |
372 | through the '-db_dev' and '-wal_dev' options. The WAL is placed with the DB, if |
373 | not specified separately. | |
1d54c3b4 AA |
374 | |
375 | [source,bash] | |
376 | ---- | |
d1fdb121 | 377 | pveceph osd create /dev/sd[X] -db_dev /dev/sd[Y] -wal_dev /dev/sd[Z] |
1d54c3b4 AA |
378 | ---- |
379 | ||
9bddef40 DC |
380 | You can directly choose the size for those with the '-db_size' and '-wal_size' |
381 | paremeters respectively. If they are not given the following values (in order) | |
382 | will be used: | |
383 | ||
352c803f TL |
384 | * bluestore_block_{db,wal}_size from ceph configuration... |
385 | ** ... database, section 'osd' | |
386 | ** ... database, section 'global' | |
387 | ** ... file, section 'osd' | |
388 | ** ... file, section 'global' | |
9bddef40 DC |
389 | * 10% (DB)/1% (WAL) of OSD size |
390 | ||
1d54c3b4 | 391 | NOTE: The DB stores BlueStore’s internal metadata and the WAL is BlueStore’s |
ee4a0e96 | 392 | internal journal or write-ahead log. It is recommended to use a fast SSD or |
1d54c3b4 AA |
393 | NVRAM for better performance. |
394 | ||
395 | ||
b3338e29 | 396 | .Ceph Filestore |
9bddef40 | 397 | |
352c803f | 398 | Before Ceph Luminous, Filestore was used as default storage type for Ceph OSDs. |
9bddef40 | 399 | Starting with Ceph Nautilus, {pve} does not support creating such OSDs with |
352c803f TL |
400 | 'pveceph' anymore. If you still want to create filestore OSDs, use |
401 | 'ceph-volume' directly. | |
1d54c3b4 AA |
402 | |
403 | [source,bash] | |
404 | ---- | |
9bddef40 | 405 | ceph-volume lvm create --filestore --data /dev/sd[X] --journal /dev/sd[Y] |
21394e70 DM |
406 | ---- |
407 | ||
081cb761 | 408 | [[pve_ceph_osd_destroy]] |
b3338e29 AA |
409 | Destroy OSDs |
410 | ~~~~~~~~~~~~ | |
be2d137e AA |
411 | |
412 | To remove an OSD via the GUI first select a {PVE} node in the tree view and go | |
413 | to the **Ceph -> OSD** panel. Select the OSD to destroy. Next click the **OUT** | |
414 | button. Once the OSD status changed from `in` to `out` click the **STOP** | |
415 | button. As soon as the status changed from `up` to `down` select **Destroy** | |
416 | from the `More` drop-down menu. | |
417 | ||
418 | To remove an OSD via the CLI run the following commands. | |
419 | [source,bash] | |
420 | ---- | |
421 | ceph osd out <ID> | |
422 | systemctl stop ceph-osd@<ID>.service | |
423 | ---- | |
424 | NOTE: The first command instructs Ceph not to include the OSD in the data | |
425 | distribution. The second command stops the OSD service. Until this time, no | |
426 | data is lost. | |
427 | ||
428 | The following command destroys the OSD. Specify the '-cleanup' option to | |
429 | additionally destroy the partition table. | |
430 | [source,bash] | |
431 | ---- | |
432 | pveceph osd destroy <ID> | |
433 | ---- | |
434 | WARNING: The above command will destroy data on the disk! | |
435 | ||
436 | ||
07fef357 | 437 | [[pve_ceph_pools]] |
b3338e29 AA |
438 | Ceph Pools |
439 | ---------- | |
1d54c3b4 | 440 | A pool is a logical group for storing objects. It holds **P**lacement |
90682f35 | 441 | **G**roups (`PG`, `pg_num`), a collection of objects. |
1d54c3b4 | 442 | |
b3338e29 AA |
443 | |
444 | Create Pools | |
445 | ~~~~~~~~~~~~ | |
446 | ||
447 | [thumbnail="screenshot/gui-ceph-pools.png"] | |
448 | ||
90682f35 TL |
449 | When no options are given, we set a default of **128 PGs**, a **size of 3 |
450 | replicas** and a **min_size of 2 replicas** for serving objects in a degraded | |
451 | state. | |
1d54c3b4 | 452 | |
5a54ef44 | 453 | NOTE: The default number of PGs works for 2-5 disks. Ceph throws a |
90682f35 | 454 | 'HEALTH_WARNING' if you have too few or too many PGs in your cluster. |
1d54c3b4 AA |
455 | |
456 | It is advised to calculate the PG number depending on your setup, you can find | |
a474ca1f | 457 | the formula and the PG calculator footnote:[PG calculator |
2798d126 | 458 | https://ceph.com/pgcalc/] online. While PGs can be increased later on, they can |
a474ca1f | 459 | never be decreased. |
1d54c3b4 AA |
460 | |
461 | ||
462 | You can create pools through command line or on the GUI on each PVE host under | |
463 | **Ceph -> Pools**. | |
464 | ||
465 | [source,bash] | |
466 | ---- | |
d1fdb121 | 467 | pveceph pool create <name> |
1d54c3b4 AA |
468 | ---- |
469 | ||
620d6725 FE |
470 | If you would like to automatically also get a storage definition for your pool, |
471 | mark the checkbox "Add storages" in the GUI or use the command line option | |
472 | '--add_storages' at pool creation. | |
21394e70 | 473 | |
1d54c3b4 AA |
474 | Further information on Ceph pool handling can be found in the Ceph pool |
475 | operation footnote:[Ceph pool operation | |
2798d126 | 476 | https://docs.ceph.com/docs/{ceph_codename}/rados/operations/pools/] |
1d54c3b4 | 477 | manual. |
21394e70 | 478 | |
166c91fe | 479 | |
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480 | Destroy Pools |
481 | ~~~~~~~~~~~~~ | |
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482 | |
483 | To destroy a pool via the GUI select a node in the tree view and go to the | |
484 | **Ceph -> Pools** panel. Select the pool to destroy and click the **Destroy** | |
485 | button. To confirm the destruction of the pool you need to enter the pool name. | |
486 | ||
487 | Run the following command to destroy a pool. Specify the '-remove_storages' to | |
488 | also remove the associated storage. | |
489 | [source,bash] | |
490 | ---- | |
491 | pveceph pool destroy <name> | |
492 | ---- | |
493 | ||
494 | NOTE: Deleting the data of a pool is a background task and can take some time. | |
495 | You will notice that the data usage in the cluster is decreasing. | |
496 | ||
76f6eca4 | 497 | [[pve_ceph_device_classes]] |
9fad507d AA |
498 | Ceph CRUSH & device classes |
499 | --------------------------- | |
500 | The foundation of Ceph is its algorithm, **C**ontrolled **R**eplication | |
501 | **U**nder **S**calable **H**ashing | |
502 | (CRUSH footnote:[CRUSH https://ceph.com/wp-content/uploads/2016/08/weil-crush-sc06.pdf]). | |
503 | ||
504 | CRUSH calculates where to store to and retrieve data from, this has the | |
505 | advantage that no central index service is needed. CRUSH works with a map of | |
506 | OSDs, buckets (device locations) and rulesets (data replication) for pools. | |
507 | ||
508 | NOTE: Further information can be found in the Ceph documentation, under the | |
2798d126 | 509 | section CRUSH map footnote:[CRUSH map https://docs.ceph.com/docs/{ceph_codename}/rados/operations/crush-map/]. |
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510 | |
511 | This map can be altered to reflect different replication hierarchies. The object | |
512 | replicas can be separated (eg. failure domains), while maintaining the desired | |
513 | distribution. | |
514 | ||
515 | A common use case is to use different classes of disks for different Ceph pools. | |
516 | For this reason, Ceph introduced the device classes with luminous, to | |
517 | accommodate the need for easy ruleset generation. | |
518 | ||
519 | The device classes can be seen in the 'ceph osd tree' output. These classes | |
520 | represent their own root bucket, which can be seen with the below command. | |
521 | ||
522 | [source, bash] | |
523 | ---- | |
524 | ceph osd crush tree --show-shadow | |
525 | ---- | |
526 | ||
527 | Example output form the above command: | |
528 | ||
529 | [source, bash] | |
530 | ---- | |
531 | ID CLASS WEIGHT TYPE NAME | |
532 | -16 nvme 2.18307 root default~nvme | |
533 | -13 nvme 0.72769 host sumi1~nvme | |
534 | 12 nvme 0.72769 osd.12 | |
535 | -14 nvme 0.72769 host sumi2~nvme | |
536 | 13 nvme 0.72769 osd.13 | |
537 | -15 nvme 0.72769 host sumi3~nvme | |
538 | 14 nvme 0.72769 osd.14 | |
539 | -1 7.70544 root default | |
540 | -3 2.56848 host sumi1 | |
541 | 12 nvme 0.72769 osd.12 | |
542 | -5 2.56848 host sumi2 | |
543 | 13 nvme 0.72769 osd.13 | |
544 | -7 2.56848 host sumi3 | |
545 | 14 nvme 0.72769 osd.14 | |
546 | ---- | |
547 | ||
548 | To let a pool distribute its objects only on a specific device class, you need | |
549 | to create a ruleset with the specific class first. | |
550 | ||
551 | [source, bash] | |
552 | ---- | |
553 | ceph osd crush rule create-replicated <rule-name> <root> <failure-domain> <class> | |
554 | ---- | |
555 | ||
556 | [frame="none",grid="none", align="left", cols="30%,70%"] | |
557 | |=== | |
558 | |<rule-name>|name of the rule, to connect with a pool (seen in GUI & CLI) | |
559 | |<root>|which crush root it should belong to (default ceph root "default") | |
560 | |<failure-domain>|at which failure-domain the objects should be distributed (usually host) | |
561 | |<class>|what type of OSD backing store to use (eg. nvme, ssd, hdd) | |
562 | |=== | |
563 | ||
564 | Once the rule is in the CRUSH map, you can tell a pool to use the ruleset. | |
565 | ||
566 | [source, bash] | |
567 | ---- | |
568 | ceph osd pool set <pool-name> crush_rule <rule-name> | |
569 | ---- | |
570 | ||
571 | TIP: If the pool already contains objects, all of these have to be moved | |
b3338e29 AA |
572 | accordingly. Depending on your setup this may introduce a big performance hit |
573 | on your cluster. As an alternative, you can create a new pool and move disks | |
9fad507d AA |
574 | separately. |
575 | ||
576 | ||
21394e70 DM |
577 | Ceph Client |
578 | ----------- | |
579 | ||
1ff5e4e8 | 580 | [thumbnail="screenshot/gui-ceph-log.png"] |
8997dd6e | 581 | |
21394e70 DM |
582 | You can then configure {pve} to use such pools to store VM or |
583 | Container images. Simply use the GUI too add a new `RBD` storage (see | |
584 | section xref:ceph_rados_block_devices[Ceph RADOS Block Devices (RBD)]). | |
585 | ||
620d6725 | 586 | You also need to copy the keyring to a predefined location for an external Ceph |
1d54c3b4 AA |
587 | cluster. If Ceph is installed on the Proxmox nodes itself, then this will be |
588 | done automatically. | |
21394e70 DM |
589 | |
590 | NOTE: The file name needs to be `<storage_id> + `.keyring` - `<storage_id>` is | |
591 | the expression after 'rbd:' in `/etc/pve/storage.cfg` which is | |
592 | `my-ceph-storage` in the following example: | |
593 | ||
594 | [source,bash] | |
595 | ---- | |
596 | mkdir /etc/pve/priv/ceph | |
597 | cp /etc/ceph/ceph.client.admin.keyring /etc/pve/priv/ceph/my-ceph-storage.keyring | |
598 | ---- | |
0840a663 | 599 | |
58f95dd7 TL |
600 | [[pveceph_fs]] |
601 | CephFS | |
602 | ------ | |
603 | ||
604 | Ceph provides also a filesystem running on top of the same object storage as | |
605 | RADOS block devices do. A **M**eta**d**ata **S**erver (`MDS`) is used to map | |
606 | the RADOS backed objects to files and directories, allowing to provide a | |
607 | POSIX-compliant replicated filesystem. This allows one to have a clustered | |
608 | highly available shared filesystem in an easy way if ceph is already used. Its | |
609 | Metadata Servers guarantee that files get balanced out over the whole Ceph | |
610 | cluster, this way even high load will not overload a single host, which can be | |
d180eb39 | 611 | an issue with traditional shared filesystem approaches, like `NFS`, for |
58f95dd7 TL |
612 | example. |
613 | ||
1e834cb2 TL |
614 | [thumbnail="screenshot/gui-node-ceph-cephfs-panel.png"] |
615 | ||
2394c306 | 616 | {pve} supports both, using an existing xref:storage_cephfs[CephFS as storage] |
58f95dd7 TL |
617 | to save backups, ISO files or container templates and creating a |
618 | hyper-converged CephFS itself. | |
619 | ||
620 | ||
621 | [[pveceph_fs_mds]] | |
622 | Metadata Server (MDS) | |
623 | ~~~~~~~~~~~~~~~~~~~~~ | |
624 | ||
625 | CephFS needs at least one Metadata Server to be configured and running to be | |
626 | able to work. One can simply create one through the {pve} web GUI's `Node -> | |
627 | CephFS` panel or on the command line with: | |
628 | ||
629 | ---- | |
630 | pveceph mds create | |
631 | ---- | |
632 | ||
633 | Multiple metadata servers can be created in a cluster. But with the default | |
634 | settings only one can be active at any time. If an MDS, or its node, becomes | |
635 | unresponsive (or crashes), another `standby` MDS will get promoted to `active`. | |
636 | One can speed up the hand-over between the active and a standby MDS up by using | |
637 | the 'hotstandby' parameter option on create, or if you have already created it | |
638 | you may set/add: | |
639 | ||
640 | ---- | |
641 | mds standby replay = true | |
642 | ---- | |
643 | ||
644 | in the ceph.conf respective MDS section. With this enabled, this specific MDS | |
645 | will always poll the active one, so that it can take over faster as it is in a | |
3580eb13 | 646 | `warm` state. But naturally, the active polling will cause some additional |
58f95dd7 TL |
647 | performance impact on your system and active `MDS`. |
648 | ||
1e834cb2 | 649 | .Multiple Active MDS |
58f95dd7 TL |
650 | |
651 | Since Luminous (12.2.x) you can also have multiple active metadata servers | |
652 | running, but this is normally only useful for a high count on parallel clients, | |
653 | as else the `MDS` seldom is the bottleneck. If you want to set this up please | |
654 | refer to the ceph documentation. footnote:[Configuring multiple active MDS | |
2798d126 | 655 | daemons https://docs.ceph.com/docs/{ceph_codename}/cephfs/multimds/] |
58f95dd7 TL |
656 | |
657 | [[pveceph_fs_create]] | |
8a38333f AA |
658 | Create CephFS |
659 | ~~~~~~~~~~~~~ | |
58f95dd7 TL |
660 | |
661 | With {pve}'s CephFS integration into you can create a CephFS easily over the | |
662 | Web GUI, the CLI or an external API interface. Some prerequisites are required | |
663 | for this to work: | |
664 | ||
665 | .Prerequisites for a successful CephFS setup: | |
666 | - xref:pve_ceph_install[Install Ceph packages], if this was already done some | |
667 | time ago you might want to rerun it on an up to date system to ensure that | |
668 | also all CephFS related packages get installed. | |
669 | - xref:pve_ceph_monitors[Setup Monitors] | |
670 | - xref:pve_ceph_monitors[Setup your OSDs] | |
671 | - xref:pveceph_fs_mds[Setup at least one MDS] | |
672 | ||
673 | After this got all checked and done you can simply create a CephFS through | |
674 | either the Web GUI's `Node -> CephFS` panel or the command line tool `pveceph`, | |
675 | for example with: | |
676 | ||
677 | ---- | |
678 | pveceph fs create --pg_num 128 --add-storage | |
679 | ---- | |
680 | ||
681 | This creates a CephFS named `'cephfs'' using a pool for its data named | |
682 | `'cephfs_data'' with `128` placement groups and a pool for its metadata named | |
683 | `'cephfs_metadata'' with one quarter of the data pools placement groups (`32`). | |
684 | Check the xref:pve_ceph_pools[{pve} managed Ceph pool chapter] or visit the | |
685 | Ceph documentation for more information regarding a fitting placement group | |
686 | number (`pg_num`) for your setup footnote:[Ceph Placement Groups | |
2798d126 | 687 | https://docs.ceph.com/docs/{ceph_codename}/rados/operations/placement-groups/]. |
58f95dd7 TL |
688 | Additionally, the `'--add-storage'' parameter will add the CephFS to the {pve} |
689 | storage configuration after it was created successfully. | |
690 | ||
691 | Destroy CephFS | |
692 | ~~~~~~~~~~~~~~ | |
693 | ||
fa9b4ee1 | 694 | WARNING: Destroying a CephFS will render all its data unusable, this cannot be |
58f95dd7 TL |
695 | undone! |
696 | ||
697 | If you really want to destroy an existing CephFS you first need to stop, or | |
620d6725 | 698 | destroy, all metadata servers (`M̀DS`). You can destroy them either over the Web |
58f95dd7 TL |
699 | GUI or the command line interface, with: |
700 | ||
701 | ---- | |
702 | pveceph mds destroy NAME | |
703 | ---- | |
704 | on each {pve} node hosting a MDS daemon. | |
705 | ||
706 | Then, you can remove (destroy) CephFS by issuing a: | |
707 | ||
708 | ---- | |
de2f8225 | 709 | ceph fs rm NAME --yes-i-really-mean-it |
58f95dd7 TL |
710 | ---- |
711 | on a single node hosting Ceph. After this you may want to remove the created | |
712 | data and metadata pools, this can be done either over the Web GUI or the CLI | |
713 | with: | |
714 | ||
715 | ---- | |
716 | pveceph pool destroy NAME | |
717 | ---- | |
0840a663 | 718 | |
6ff32926 | 719 | |
081cb761 AA |
720 | Ceph maintenance |
721 | ---------------- | |
af6f59f4 | 722 | |
081cb761 AA |
723 | Replace OSDs |
724 | ~~~~~~~~~~~~ | |
af6f59f4 | 725 | |
081cb761 AA |
726 | One of the common maintenance tasks in Ceph is to replace a disk of an OSD. If |
727 | a disk is already in a failed state, then you can go ahead and run through the | |
728 | steps in xref:pve_ceph_osd_destroy[Destroy OSDs]. Ceph will recreate those | |
af6f59f4 TL |
729 | copies on the remaining OSDs if possible. This rebalancing will start as soon |
730 | as an OSD failure is detected or an OSD was actively stopped. | |
731 | ||
732 | NOTE: With the default size/min_size (3/2) of a pool, recovery only starts when | |
733 | `size + 1` nodes are available. The reason for this is that the Ceph object | |
734 | balancer xref:pve_ceph_device_classes[CRUSH] defaults to a full node as | |
735 | `failure domain'. | |
081cb761 AA |
736 | |
737 | To replace a still functioning disk, on the GUI go through the steps in | |
738 | xref:pve_ceph_osd_destroy[Destroy OSDs]. The only addition is to wait until | |
739 | the cluster shows 'HEALTH_OK' before stopping the OSD to destroy it. | |
740 | ||
741 | On the command line use the following commands. | |
742 | ---- | |
743 | ceph osd out osd.<id> | |
744 | ---- | |
745 | ||
746 | You can check with the command below if the OSD can be safely removed. | |
747 | ---- | |
748 | ceph osd safe-to-destroy osd.<id> | |
749 | ---- | |
750 | ||
751 | Once the above check tells you that it is save to remove the OSD, you can | |
752 | continue with following commands. | |
753 | ---- | |
754 | systemctl stop ceph-osd@<id>.service | |
755 | pveceph osd destroy <id> | |
756 | ---- | |
757 | ||
758 | Replace the old disk with the new one and use the same procedure as described | |
759 | in xref:pve_ceph_osd_create[Create OSDs]. | |
760 | ||
835f322d TL |
761 | Trim/Discard |
762 | ~~~~~~~~~~~~ | |
081cb761 AA |
763 | It is a good measure to run 'fstrim' (discard) regularly on VMs or containers. |
764 | This releases data blocks that the filesystem isn’t using anymore. It reduces | |
c78cd2b6 AA |
765 | data usage and resource load. Most modern operating systems issue such discard |
766 | commands to their disks regularly. You only need to ensure that the Virtual | |
767 | Machines enable the xref:qm_hard_disk_discard[disk discard option]. | |
081cb761 | 768 | |
c998bdf2 | 769 | [[pveceph_scrub]] |
081cb761 AA |
770 | Scrub & Deep Scrub |
771 | ~~~~~~~~~~~~~~~~~~ | |
772 | Ceph ensures data integrity by 'scrubbing' placement groups. Ceph checks every | |
773 | object in a PG for its health. There are two forms of Scrubbing, daily | |
b16f8c5f TL |
774 | cheap metadata checks and weekly deep data checks. The weekly deep scrub reads |
775 | the objects and uses checksums to ensure data integrity. If a running scrub | |
776 | interferes with business (performance) needs, you can adjust the time when | |
777 | scrubs footnote:[Ceph scrubbing https://docs.ceph.com/docs/{ceph_codename}/rados/configuration/osd-config-ref/#scrubbing] | |
081cb761 AA |
778 | are executed. |
779 | ||
780 | ||
10df14fb TL |
781 | Ceph monitoring and troubleshooting |
782 | ----------------------------------- | |
783 | A good start is to continuosly monitor the ceph health from the start of | |
784 | initial deployment. Either through the ceph tools itself, but also by accessing | |
785 | the status through the {pve} link:api-viewer/index.html[API]. | |
6ff32926 | 786 | |
10df14fb TL |
787 | The following ceph commands below can be used to see if the cluster is healthy |
788 | ('HEALTH_OK'), if there are warnings ('HEALTH_WARN'), or even errors | |
789 | ('HEALTH_ERR'). If the cluster is in an unhealthy state the status commands | |
620d6725 | 790 | below will also give you an overview of the current events and actions to take. |
6ff32926 AA |
791 | |
792 | ---- | |
10df14fb TL |
793 | # single time output |
794 | pve# ceph -s | |
795 | # continuously output status changes (press CTRL+C to stop) | |
796 | pve# ceph -w | |
6ff32926 AA |
797 | ---- |
798 | ||
799 | To get a more detailed view, every ceph service has a log file under | |
800 | `/var/log/ceph/` and if there is not enough detail, the log level can be | |
2798d126 | 801 | adjusted footnote:[Ceph log and debugging https://docs.ceph.com/docs/{ceph_codename}/rados/troubleshooting/log-and-debug/]. |
6ff32926 AA |
802 | |
803 | You can find more information about troubleshooting | |
2798d126 | 804 | footnote:[Ceph troubleshooting https://docs.ceph.com/docs/{ceph_codename}/rados/troubleshooting/] |
620d6725 | 805 | a Ceph cluster on the official website. |
6ff32926 AA |
806 | |
807 | ||
0840a663 DM |
808 | ifdef::manvolnum[] |
809 | include::pve-copyright.adoc[] | |
810 | endif::manvolnum[] |