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1 | [[chapter-storage]] | |
2 | ifdef::manvolnum[] | |
3 | PVE({manvolnum}) | |
4 | ================ | |
5 | include::attributes.txt[] | |
6 | ||
7 | NAME | |
8 | ---- | |
9 | ||
10 | pvesm - Proxmox VE Storage Manager | |
11 | ||
12 | ||
13 | SYNOPSYS | |
14 | -------- | |
15 | ||
16 | include::pvesm.1-synopsis.adoc[] | |
17 | ||
18 | DESCRIPTION | |
19 | ----------- | |
20 | endif::manvolnum[] | |
21 | ||
22 | ifndef::manvolnum[] | |
23 | {pve} Storage | |
24 | ============= | |
25 | include::attributes.txt[] | |
26 | endif::manvolnum[] | |
27 | ||
28 | The {pve} storage model is very flexible. Virtual machine images | |
29 | can either be stored on one or several local storages, or on shared | |
30 | storage like NFS or iSCSI (NAS, SAN). There are no limits, and you may | |
31 | configure as many storage pools as you like. You can use all | |
32 | storage technologies available for Debian Linux. | |
33 | ||
34 | One major benefit of storing VMs on shared storage is the ability to | |
35 | live-migrate running machines without any downtime, as all nodes in | |
36 | the cluster have direct access to VM disk images. There is no need to | |
37 | copy VM image data, so live migration is very fast in that case. | |
38 | ||
39 | The storage library (package 'libpve-storage-perl') uses a flexible | |
40 | plugin system to provide a common interface to all storage types. This | |
41 | can be easily adopted to include further storage types in future. | |
42 | ||
43 | ||
44 | Storage Types | |
45 | ------------- | |
46 | ||
47 | There are basically two different classes of storage types: | |
48 | ||
49 | Block level storage:: | |
50 | ||
51 | Allows to store large 'raw' images. It is usually not possible to store | |
52 | other files (ISO, backups, ..) on such storage types. Most modern | |
53 | block level storage implementations support snapshots and clones. | |
54 | RADOS, Sheepdog and DRBD are distributed systems, replicating storage | |
55 | data to different nodes. | |
56 | ||
57 | File level storage:: | |
58 | ||
59 | They allow access to a full featured (POSIX) file system. They are | |
60 | more flexible, and allows you to store any content type. ZFS is | |
61 | probably the most advanced system, and it has full support for | |
62 | snapshots and clones. | |
63 | ||
64 | ||
65 | .Available storage types | |
66 | [width="100%",cols="<d,1*m,4*d",options="header"] | |
67 | |=========================================================== | |
68 | |Description |PVE type |Level |Shared|Snapshots|Stable | |
69 | |ZFS (local) |zfspool |file |no |yes |yes | |
70 | |Directory |dir |file |no |no |yes | |
71 | |NFS |nfs |file |yes |no |yes | |
72 | |GlusterFS |glusterfs |file |yes |no |yes | |
73 | |LVM |lvm |block |no |no |yes | |
74 | |LVM-thin |lvmthin |block |no |yes |yes | |
75 | |iSCSI/kernel |iscsi |block |yes |no |yes | |
76 | |iSCSI/libiscsi |iscsidirect |block |yes |no |yes | |
77 | |Ceph/RBD |rbd |block |yes |yes |yes | |
78 | |Sheepdog |sheepdog |block |yes |yes |beta | |
79 | |DRBD9 |drbd |block |yes |yes |beta | |
80 | |ZFS over iSCSI |zfs |block |yes |yes |yes | |
81 | |========================================================= | |
82 | ||
83 | TIP: It is possible to use LVM on top of an iSCSI storage. That way | |
84 | you get a 'shared' LVM storage. | |
85 | ||
86 | Thin provisioning | |
87 | ~~~~~~~~~~~~~~~~~ | |
88 | ||
89 | A number of storages, and the Qemu image format `qcow2`, support _thin | |
90 | provisioning_. With thin provisioning activated, only the blocks that | |
91 | the guest system actually use will be written to the storage. | |
92 | ||
93 | Say for instance you create a VM with a 32GB hard disk, and after | |
94 | installing the guest system OS, the root filesystem of the VM contains | |
95 | 3 GB of data. In that case only 3GB are written to the storage, even | |
96 | if the guest VM sees a 32GB hard drive. In this way thin provisioning | |
97 | allows you to create disk images which are larger than the currently | |
98 | available storage blocks. You can create large disk images for your | |
99 | VMs, and when the need arises, add more disks to your storage without | |
100 | resizing the VMs filesystems. | |
101 | ||
102 | All storage types which have the 'Snapshots' feature also support thin | |
103 | provisioning. | |
104 | ||
105 | CAUTION: If a storage runs full, all guests using volumes on that | |
106 | storage receives IO error. This can cause file system inconsistencies | |
107 | and may corrupt your data. So it is advisable to avoid | |
108 | over-provisioning of your storage resources, or carefully observe | |
109 | free space to avoid such conditions. | |
110 | ||
111 | Storage Configuration | |
112 | --------------------- | |
113 | ||
114 | All {pve} related storage configuration is stored within a single text | |
115 | file at '/etc/pve/storage.cfg'. As this file is within '/etc/pve/', it | |
116 | gets automatically distributed to all cluster nodes. So all nodes | |
117 | share the same storage configuration. | |
118 | ||
119 | Sharing storage configuration make perfect sense for shared storage, | |
120 | because the same 'shared' storage is accessible from all nodes. But is | |
121 | also useful for local storage types. In this case such local storage | |
122 | is available on all nodes, but it is physically different and can have | |
123 | totally different content. | |
124 | ||
125 | Storage Pools | |
126 | ~~~~~~~~~~~~~ | |
127 | ||
128 | Each storage pool has a `<type>`, and is uniquely identified by its `<STORAGE_ID>`. A pool configuration looks like this: | |
129 | ||
130 | ---- | |
131 | <type>: <STORAGE_ID> | |
132 | <property> <value> | |
133 | <property> <value> | |
134 | ... | |
135 | ---- | |
136 | ||
137 | The `<type>: <STORAGE_ID>` line starts the pool definition, which is then | |
138 | followed by a list of properties. Most properties have values, but some of | |
139 | them come with reasonable default. In that case you can omit the value. | |
140 | ||
141 | To be more specific, take a look at the default storage configuration | |
142 | after installation. It contains one special local storage pool named | |
143 | `local`, which refers to the directory '/var/lib/vz' and is always | |
144 | available. The {pve} installer creates additional storage entries | |
145 | depending on the storage type chosen at installation time. | |
146 | ||
147 | .Default storage configuration ('/etc/pve/storage.cfg') | |
148 | ---- | |
149 | dir: local | |
150 | path /var/lib/vz | |
151 | content iso,vztmpl,backup | |
152 | ||
153 | # default image store on LVM based installation | |
154 | lvmthin: local-lvm | |
155 | thinpool data | |
156 | vgname pve | |
157 | content rootdir,images | |
158 | ||
159 | # default image store on ZFS based installation | |
160 | zfspool: local-zfs | |
161 | pool rpool/data | |
162 | sparse | |
163 | content images,rootdir | |
164 | ---- | |
165 | ||
166 | Common Storage Properties | |
167 | ~~~~~~~~~~~~~~~~~~~~~~~~~ | |
168 | ||
169 | A few storage properties are common among different storage types. | |
170 | ||
171 | nodes:: | |
172 | ||
173 | List of cluster node names where this storage is | |
174 | usable/accessible. One can use this property to restrict storage | |
175 | access to a limited set of nodes. | |
176 | ||
177 | content:: | |
178 | ||
179 | A storage can support several content types, for example virtual disk | |
180 | images, cdrom iso images, container templates or container root | |
181 | directories. Not all storage types support all content types. One can set | |
182 | this property to select for what this storage is used for. | |
183 | ||
184 | images::: | |
185 | ||
186 | KVM-Qemu VM images. | |
187 | ||
188 | rootdir::: | |
189 | ||
190 | Allow to store container data. | |
191 | ||
192 | vztmpl::: | |
193 | ||
194 | Container templates. | |
195 | ||
196 | backup::: | |
197 | ||
198 | Backup files ('vzdump'). | |
199 | ||
200 | iso::: | |
201 | ||
202 | ISO images | |
203 | ||
204 | shared:: | |
205 | ||
206 | Mark storage as shared. | |
207 | ||
208 | disable:: | |
209 | ||
210 | You can use this flag to disable the storage completely. | |
211 | ||
212 | maxfiles:: | |
213 | ||
214 | Maximal number of backup files per VM. Use `0` for unlimted. | |
215 | ||
216 | format:: | |
217 | ||
218 | Default image format (`raw|qcow2|vmdk`) | |
219 | ||
220 | ||
221 | WARNING: It is not advisable to use the same storage pool on different | |
222 | {pve} clusters. Some storage operation need exclusive access to the | |
223 | storage, so proper locking is required. While this is implemented | |
224 | within a cluster, it does not work between different clusters. | |
225 | ||
226 | ||
227 | Volumes | |
228 | ------- | |
229 | ||
230 | We use a special notation to address storage data. When you allocate | |
231 | data from a storage pool, it returns such a volume identifier. A volume | |
232 | is identified by the `<STORAGE_ID>`, followed by a storage type | |
233 | dependent volume name, separated by colon. A valid `<VOLUME_ID>` looks | |
234 | like: | |
235 | ||
236 | local:230/example-image.raw | |
237 | ||
238 | local:iso/debian-501-amd64-netinst.iso | |
239 | ||
240 | local:vztmpl/debian-5.0-joomla_1.5.9-1_i386.tar.gz | |
241 | ||
242 | iscsi-storage:0.0.2.scsi-14f504e46494c4500494b5042546d2d646744372d31616d61 | |
243 | ||
244 | To get the filesystem path for a `<VOLUME_ID>` use: | |
245 | ||
246 | pvesm path <VOLUME_ID> | |
247 | ||
248 | Volume Ownership | |
249 | ~~~~~~~~~~~~~~~~ | |
250 | ||
251 | There exists an ownership relation for 'image' type volumes. Each such | |
252 | volume is owned by a VM or Container. For example volume | |
253 | `local:230/example-image.raw` is owned by VM 230. Most storage | |
254 | backends encodes this ownership information into the volume name. | |
255 | ||
256 | When you remove a VM or Container, the system also removes all | |
257 | associated volumes which are owned by that VM or Container. | |
258 | ||
259 | ||
260 | Using the Command Line Interface | |
261 | -------------------------------- | |
262 | ||
263 | It is recommended to familiarize yourself with the concept behind storage | |
264 | pools and volume identifiers, but in real life, you are not forced to do any | |
265 | of those low level operations on the command line. Normally, | |
266 | allocation and removal of volumes is done by the VM and Container | |
267 | management tools. | |
268 | ||
269 | Nevertheless, there is a command line tool called 'pvesm' ({pve} | |
270 | storage manager), which is able to perform common storage management | |
271 | tasks. | |
272 | ||
273 | ||
274 | Examples | |
275 | ~~~~~~~~ | |
276 | ||
277 | Add storage pools | |
278 | ||
279 | pvesm add <TYPE> <STORAGE_ID> <OPTIONS> | |
280 | pvesm add dir <STORAGE_ID> --path <PATH> | |
281 | pvesm add nfs <STORAGE_ID> --path <PATH> --server <SERVER> --export <EXPORT> | |
282 | pvesm add lvm <STORAGE_ID> --vgname <VGNAME> | |
283 | pvesm add iscsi <STORAGE_ID> --portal <HOST[:PORT]> --target <TARGET> | |
284 | ||
285 | Disable storage pools | |
286 | ||
287 | pvesm set <STORAGE_ID> --disable 1 | |
288 | ||
289 | Enable storage pools | |
290 | ||
291 | pvesm set <STORAGE_ID> --disable 0 | |
292 | ||
293 | Change/set storage options | |
294 | ||
295 | pvesm set <STORAGE_ID> <OPTIONS> | |
296 | pvesm set <STORAGE_ID> --shared 1 | |
297 | pvesm set local --format qcow2 | |
298 | pvesm set <STORAGE_ID> --content iso | |
299 | ||
300 | Remove storage pools. This does not delete any data, and does not | |
301 | disconnect or unmount anything. It just removes the storage | |
302 | configuration. | |
303 | ||
304 | pvesm remove <STORAGE_ID> | |
305 | ||
306 | Allocate volumes | |
307 | ||
308 | pvesm alloc <STORAGE_ID> <VMID> <name> <size> [--format <raw|qcow2>] | |
309 | ||
310 | Allocate a 4G volume in local storage. The name is auto-generated if | |
311 | you pass an empty string as `<name>` | |
312 | ||
313 | pvesm alloc local <VMID> '' 4G | |
314 | ||
315 | Free volumes | |
316 | ||
317 | pvesm free <VOLUME_ID> | |
318 | ||
319 | WARNING: This really destroys all volume data. | |
320 | ||
321 | List storage status | |
322 | ||
323 | pvesm status | |
324 | ||
325 | List storage contents | |
326 | ||
327 | pvesm list <STORAGE_ID> [--vmid <VMID>] | |
328 | ||
329 | List volumes allocated by VMID | |
330 | ||
331 | pvesm list <STORAGE_ID> --vmid <VMID> | |
332 | ||
333 | List iso images | |
334 | ||
335 | pvesm list <STORAGE_ID> --iso | |
336 | ||
337 | List container templates | |
338 | ||
339 | pvesm list <STORAGE_ID> --vztmpl | |
340 | ||
341 | Show filesystem path for a volume | |
342 | ||
343 | pvesm path <VOLUME_ID> | |
344 | ||
345 | ifdef::wiki[] | |
346 | ||
347 | See Also | |
348 | -------- | |
349 | ||
350 | * link:/wiki/Storage:_Directory[Storage: Directory] | |
351 | ||
352 | * link:/wiki/Storage:_GlusterFS[Storage: GlusterFS] | |
353 | ||
354 | * link:/wiki/Storage:_User_Mode_iSCSI[Storage: User Mode iSCSI] | |
355 | ||
356 | * link:/wiki/Storage:_iSCSI[Storage: iSCSI] | |
357 | ||
358 | * link:/wiki/Storage:_LVM[Storage: LVM] | |
359 | ||
360 | * link:/wiki/Storage:_LVM_Thin[Storage: LVM Thin] | |
361 | ||
362 | * link:/wiki/Storage:_NFS[Storage: NFS] | |
363 | ||
364 | * link:/wiki/Storage:_RBD[Storage: RBD] | |
365 | ||
366 | * link:/wiki/Storage:_ZFS[Storage: ZFS] | |
367 | ||
368 | ||
369 | endif::wiki[] | |
370 | ||
371 | ifndef::wiki[] | |
372 | ||
373 | // backend documentation | |
374 | ||
375 | include::pve-storage-dir.adoc[] | |
376 | ||
377 | include::pve-storage-nfs.adoc[] | |
378 | ||
379 | include::pve-storage-glusterfs.adoc[] | |
380 | ||
381 | include::pve-storage-zfspool.adoc[] | |
382 | ||
383 | include::pve-storage-lvm.adoc[] | |
384 | ||
385 | include::pve-storage-lvmthin.adoc[] | |
386 | ||
387 | include::pve-storage-iscsi.adoc[] | |
388 | ||
389 | include::pve-storage-iscsidirect.adoc[] | |
390 | ||
391 | include::pve-storage-rbd.adoc[] | |
392 | ||
393 | ||
394 | ||
395 | ifdef::manvolnum[] | |
396 | include::pve-copyright.adoc[] | |
397 | endif::manvolnum[] | |
398 | ||
399 | endif::wiki[] | |
400 |