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1 | ifdef::manvolnum[] |
2 | PVE({manvolnum}) | |
3 | ================ | |
38fd0958 | 4 | include::attributes.txt[] |
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5 | |
6 | NAME | |
7 | ---- | |
8 | ||
9 | qm - Qemu/KVM Virtual Machine Manager | |
10 | ||
11 | ||
12 | SYNOPSYS | |
13 | -------- | |
14 | ||
15 | include::qm.1-synopsis.adoc[] | |
16 | ||
17 | DESCRIPTION | |
18 | ----------- | |
19 | endif::manvolnum[] | |
20 | ||
21 | ifndef::manvolnum[] | |
22 | Qemu/KVM Virtual Machines | |
23 | ========================= | |
38fd0958 | 24 | include::attributes.txt[] |
f69cfd23 DM |
25 | endif::manvolnum[] |
26 | ||
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27 | // deprecates |
28 | // http://pve.proxmox.com/wiki/Container_and_Full_Virtualization | |
29 | // http://pve.proxmox.com/wiki/KVM | |
30 | // http://pve.proxmox.com/wiki/Qemu_Server | |
31 | ||
32 | Qemu (short form for Quick Emulator) is an opensource hypervisor that emulates a | |
33 | physical computer. From the perspective of the host system where Qemu is | |
34 | running, Qemu is a user program which has access to a number of local resources | |
35 | like partitions, files, network cards which are then passed to an | |
189d3661 | 36 | emulated computer which sees them as if they were real devices. |
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37 | |
38 | A guest operating system running in the emulated computer accesses these | |
39 | devices, and runs as it were running on real hardware. For instance you can pass | |
40 | an iso image as a parameter to Qemu, and the OS running in the emulated computer | |
189d3661 | 41 | will see a real CDROM inserted in a CD drive. |
c4cba5d7 | 42 | |
189d3661 | 43 | Qemu can emulates a great variety of hardware from ARM to Sparc, but {pve} is |
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44 | only concerned with 32 and 64 bits PC clone emulation, since it represents the |
45 | overwhelming majority of server hardware. The emulation of PC clones is also one | |
46 | of the fastest due to the availability of processor extensions which greatly | |
47 | speed up Qemu when the emulated architecture is the same as the host | |
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48 | architecture. |
49 | ||
50 | NOTE: You may sometimes encounter the term _KVM_ (Kernel-based Virtual Machine). | |
51 | It means that Qemu is running with the support of the virtualization processor | |
52 | extensions, via the Linux kvm module. In the context of {pve} _Qemu_ and | |
53 | _KVM_ can be use interchangeably as Qemu in {pve} will always try to load the kvm | |
54 | module. | |
55 | ||
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56 | Qemu inside {pve} runs as a root process, since this is required to access block |
57 | and PCI devices. | |
58 | ||
59 | Emulated devices and paravirtualized devices | |
60 | -------------------------------------------- | |
61 | ||
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62 | The PC hardware emulated by Qemu includes a mainboard, network controllers, |
63 | scsi, ide and sata controllers, serial ports (the complete list can be seen in | |
64 | the `kvm(1)` man page) all of them emulated in software. All these devices | |
65 | are the exact software equivalent of existing hardware devices, and if the OS | |
66 | running in the guest has the proper drivers it will use the devices as if it | |
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67 | were running on real hardware. This allows Qemu to runs _unmodified_ operating |
68 | systems. | |
69 | ||
70 | This however has a performance cost, as running in software what was meant to | |
71 | run in hardware involves a lot of extra work for the host CPU. To mitigate this, | |
72 | Qemu can present to the guest operating system _paravirtualized devices_, where | |
73 | the guest OS recognizes it is running inside Qemu and cooperates with the | |
74 | hypervisor. | |
75 | ||
76 | Qemu relies on the virtio virtualization standard, and is thus able to presente | |
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77 | paravirtualized virtio devices, which includes a paravirtualized generic disk |
78 | controller, a paravirtualized network card, a paravirtualized serial port, | |
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79 | a paravirtualized SCSI controller, etc ... |
80 | ||
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81 | It is highly recommended to use the virtio devices whenever you can, as they |
82 | provide a big performance improvement. Using the virtio generic disk controller | |
83 | versus an emulated IDE controller will double the sequential write throughput, | |
84 | as measured with `bonnie++(8)`. Using the virtio network interface can deliver | |
c4cba5d7 | 85 | up to three times the throughput of an emulated Intel E1000 network card, as |
189d3661 | 86 | measured with `iperf(1)`. footnote:[See this benchmark on the KVM wiki |
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87 | http://www.linux-kvm.org/page/Using_VirtIO_NIC] |
88 | ||
89 | Virtual Machines settings | |
90 | ------------------------- | |
91 | Generally speaking {pve} tries to choose sane defaults for virtual machines | |
92 | (VM). Make sure you understand the meaning of the settings you change, as it | |
93 | could incur a performance slowdown, or putting your data at risk. | |
94 | ||
95 | General Settings | |
96 | ~~~~~~~~~~~~~~~~ | |
97 | General settings of a VM include | |
98 | ||
99 | * the *Node* : the physical server on which the VM will run | |
100 | * the *VM ID*: a unique number in this {pve} installation used to identify your VM | |
101 | * *Name*: a free form text string you can use to describe the VM | |
102 | * *Resource Pool*: a logical group of VMs | |
103 | ||
104 | OS Settings | |
105 | ~~~~~~~~~~~ | |
106 | When creating a VM, setting the proper Operating System(OS) allows {pve} to | |
107 | optimize some low level parameters. For instance Windows OS expect the BIOS | |
108 | clock to use the local time, while Unix based OS expect the BIOS clock to have | |
109 | the UTC time. | |
110 | ||
111 | Hard Disk | |
112 | ~~~~~~~~~ | |
2ec49380 | 113 | Qemu can emulate a number of storage controllers: |
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114 | |
115 | * the *IDE* controller, has a design which goes back to the 1984 PC/AT disk | |
116 | controller. Even if this controller has been superseded by more more designs, | |
117 | each and every OS you can think has support for it, making it a great choice | |
118 | if you want to run an OS released before 2003. You can connect up to 4 devices | |
119 | on this controller. | |
120 | ||
121 | * the *SATA* (Serial ATA) controller, dating from 2003, has a more modern | |
122 | design, allowing higher throughput and a greater number of devices to be | |
123 | connected. You can connect up to 6 devices on this controller. | |
124 | ||
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125 | * the *SCSI* controller, designed in 1985, is commonly found on server grade |
126 | hardware, and can connect up to 14 storage devices. {pve} emulates by default a | |
127 | LSI 53C895A controller. + | |
128 | A SCSI controller of type _Virtio_ is the recommended setting if you aim for | |
129 | performance and is automatically selected for newly created Linux VMs since | |
130 | {pve} 4.3. Linux distributions have support for this controller since 2012, and | |
c4cba5d7 | 131 | FreeBSD since 2014. For Windows OSes, you need to provide an extra iso |
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132 | containing the drivers during the installation. |
133 | // https://pve.proxmox.com/wiki/Paravirtualized_Block_Drivers_for_Windows#During_windows_installation. | |
134 | ||
135 | * The *Virtio* controller, also called virtio-blk to distinguish from | |
136 | the Virtio SCSI controller, is an older type of paravirtualized controller | |
137 | which has been superseded in features by the Virtio SCSI Controller. | |
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138 | |
139 | On each controller you attach a number of emulated hard disks, which are backed | |
140 | by a file or a block device residing in the configured storage. The choice of | |
141 | a storage type will determine the format of the hard disk image. Storages which | |
142 | present block devices (LVM, ZFS, Ceph) will require the *raw disk image format*, | |
143 | whereas files based storages (Ext4, NFS, GlusterFS) will let you to choose | |
144 | either the *raw disk image format* or the *QEMU image format*. | |
145 | ||
146 | * the *QEMU image format* is a copy on write format which allows snapshots, and | |
147 | thin provisioning of the disk image. | |
189d3661 DC |
148 | * the *raw disk image* is a bit-to-bit image of a hard disk, similar to what |
149 | you would get when executing the `dd` command on a block device in Linux. This | |
150 | format do not support thin provisioning or snapshotting by itself, requiring | |
151 | cooperation from the storage layer for these tasks. It is however 10% faster | |
152 | than the *QEMU image format*. footnote:[See this benchmark for details | |
c4cba5d7 | 153 | http://events.linuxfoundation.org/sites/events/files/slides/CloudOpen2013_Khoa_Huynh_v3.pdf] |
189d3661 | 154 | * the *VMware image format* only makes sense if you intend to import/export the |
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155 | disk image to other hypervisors. |
156 | ||
157 | Setting the *Cache* mode of the hard drive will impact how the host system will | |
158 | notify the guest systems of block write completions. The *No cache* default | |
159 | means that the guest system will be notified that a write is complete when each | |
160 | block reaches the physical storage write queue, ignoring the host page cache. | |
161 | This provides a good balance between safety and speed. | |
162 | ||
163 | If you want the {pve} backup manager to skip a disk when doing a backup of a VM, | |
164 | you can set the *No backup* option on that disk. | |
165 | ||
166 | If your storage supports _thin provisioning_ (see the storage chapter in the | |
167 | {pve} guide), and your VM has a *SCSI* controller you can activate the *Discard* | |
168 | option on the hard disks connected to that controller. With *Discard* enabled, | |
169 | when the filesystem of a VM marks blocks as unused after removing files, the | |
170 | emulated SCSI controller will relay this information to the storage, which will | |
171 | then shrink the disk image accordingly. | |
172 | ||
af9c6de1 | 173 | .IO Thread |
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174 | The option *IO Thread* can only be enabled when using a disk with the *VirtIO* controller, |
175 | or with the *SCSI* controller, when the emulated controller type is *VirtIO SCSI*. | |
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176 | With this enabled, Qemu uses one thread per disk, instead of one thread for all, |
177 | so it should increase performance when using multiple disks. | |
178 | Note that backups do not currently work with *IO Thread* enabled. | |
179 | ||
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180 | CPU |
181 | ~~~ | |
182 | A *CPU socket* is a physical slot on a PC motherboard where you can plug a CPU. | |
183 | This CPU can then contain one or many *cores*, which are independent | |
184 | processing units. Whether you have a single CPU socket with 4 cores, or two CPU | |
185 | sockets with two cores is mostly irrelevant from a performance point of view. | |
186 | However some software is licensed depending on the number of sockets you have in | |
187 | your machine, in that case it makes sense to set the number of of sockets to | |
188 | what the license allows you, and increase the number of cores. + | |
189 | Increasing the number of virtual cpus (cores and sockets) will usually provide a | |
190 | performance improvement though that is heavily dependent on the use of the VM. | |
191 | Multithreaded applications will of course benefit from a large number of | |
192 | virtual cpus, as for each virtual cpu you add, Qemu will create a new thread of | |
193 | execution on the host system. If you're not sure about the workload of your VM, | |
194 | it is usually a safe bet to set the number of *Total cores* to 2. | |
195 | ||
196 | NOTE: It is perfectly safe to set the _overall_ number of total cores in all | |
197 | your VMs to be greater than the number of of cores you have on your server (ie. | |
198 | 4 VMs with each 4 Total cores running in a 8 core machine is OK) In that case | |
199 | the host system will balance the Qemu execution threads between your server | |
200 | cores just like if you were running a standard multithreaded application. | |
201 | However {pve} will prevent you to allocate on a _single_ machine more vcpus than | |
202 | physically available, as this will only bring the performance down due to the | |
203 | cost of context switches. | |
204 | ||
205 | Qemu can emulate a number different of *CPU types* from 486 to the latest Xeon | |
206 | processors. Each new processor generation adds new features, like hardware | |
207 | assisted 3d rendering, random number generation, memory protection, etc ... | |
208 | Usually you should select for your VM a processor type which closely matches the | |
209 | CPU of the host system, as it means that the host CPU features (also called _CPU | |
210 | flags_ ) will be available in your VMs. If you want an exact match, you can set | |
211 | the CPU type to *host* in which case the VM will have exactly the same CPU flags | |
212 | as your host system. + | |
213 | This has a downside though. If you want to do a live migration of VMs between | |
214 | different hosts, your VM might end up on a new system with a different CPU type. | |
215 | If the CPU flags passed to the guest are missing, the qemu process will stop. To | |
216 | remedy this Qemu has also its own CPU type *kvm64*, that {pve} uses by defaults. | |
217 | kvm64 is a Pentium 4 look a like CPU type, which has a reduced CPU flags set, | |
218 | but is guaranteed to work everywhere. + | |
219 | In short, if you care about live migration and moving VMs between nodes, leave | |
220 | the kvm64 default. If you don’t care about live migration, set the CPU type to | |
221 | host, as in theory this will give your guests maximum performance. | |
222 | ||
223 | You can also optionally emulate a *NUMA* architecture in your VMs. The basics of | |
224 | the NUMA architecture mean that instead of having a global memory pool available | |
225 | to all your cores, the memory is spread into local banks close to each socket. | |
226 | This can bring speed improvements as the memory bus is not a bottleneck | |
227 | anymore. If your system has a NUMA architecture footnote:[if the command | |
228 | `numactl --hardware | grep available` returns more than one node, then your host | |
229 | system has a NUMA architecture] we recommend to activate the option, as this | |
230 | will allow proper distribution of the VM resources on the host system. This | |
231 | option is also required in {pve} to allow hotplugging of cores and RAM to a VM. | |
232 | ||
233 | If the NUMA option is used, it is recommended to set the number of sockets to | |
234 | the number of sockets of the host system. | |
235 | ||
236 | Memory | |
237 | ~~~~~~ | |
238 | For each VM you have the option to set a fixed size memory or asking | |
239 | {pve} to dynamically allocate memory based on the current RAM usage of the | |
240 | host. | |
241 | ||
242 | When choosing a *fixed size memory* {pve} will simply allocate what you | |
243 | specify to your VM. | |
244 | ||
245 | // see autoballoon() in pvestatd.pm | |
246 | When choosing to *automatically allocate memory*, {pve} will make sure that the | |
247 | minimum amount you specified is always available to the VM, and if RAM usage on | |
248 | the host is below 80%, will dynamically add memory to the guest up to the | |
249 | maximum memory specified. + | |
250 | When the host is becoming short on RAM, the VM will then release some memory | |
251 | back to the host, swapping running processes if needed and starting the oom | |
252 | killer in last resort. The passing around of memory between host and guest is | |
253 | done via a special `balloon` kernel driver running inside the guest, which will | |
254 | grab or release memory pages from the host. | |
255 | footnote:[A good explanation of the inner workings of the balloon driver can be found here https://rwmj.wordpress.com/2010/07/17/virtio-balloon/] | |
256 | ||
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257 | When multiple VMs use the autoallocate facility, it is possible to set a |
258 | *Shares* coefficient which indicates the relative amount of the free host memory | |
259 | that each VM shoud take. Suppose for instance you have four VMs, three of them | |
260 | running a HTTP server and the last one is a database server. To cache more | |
261 | database blocks in the database server RAM, you would like to prioritize the | |
262 | database VM when spare RAM is available. For this you assign a Shares property | |
263 | of 3000 to the database VM, leaving the other VMs to the Shares default setting | |
264 | of 1000. The host server has 32GB of RAM, and is curring using 16GB, leaving 32 | |
265 | * 80/100 - 16 = 9GB RAM to be allocated to the VMs. The database VM will get 9 * | |
266 | 3000 / (3000 + 1000 + 1000 + 1000) = 4.5 GB extra RAM and each HTTP server will | |
267 | get 1/5 GB. | |
268 | ||
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269 | All Linux distributions released after 2010 have the balloon kernel driver |
270 | included. For Windows OSes, the balloon driver needs to be added manually and can | |
271 | incur a slowdown of the guest, so we don't recommend using it on critical | |
272 | systems. | |
273 | // see https://forum.proxmox.com/threads/solved-hyper-threading-vs-no-hyper-threading-fixed-vs-variable-memory.20265/ | |
274 | ||
275 | When allocating RAMs to your VMs, a good rule of thumb is always to leave 1GB | |
276 | of RAM available to the host. | |
277 | ||
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278 | Network Device |
279 | ~~~~~~~~~~~~~~ | |
280 | Each VM can have many _Network interface controllers_ (NIC), of four different | |
281 | types: | |
282 | ||
283 | * *Intel E1000* is the default, and emulates an Intel Gigabit network card. | |
284 | * the *VirtIO* paravirtualized NIC should be used if you aim for maximum | |
285 | performance. Like all VirtIO devices, the guest OS should have the proper driver | |
286 | installed. | |
287 | * the *Realtek 8139* emulates an older 100 MB/s network card, and should | |
288 | only be used when emulating older operating systems ( released before 2002 ) | |
289 | * the *vmxnet3* is another paravirtualized device, which should only be used | |
290 | when importing a VM from another hypervisor. | |
291 | ||
292 | {pve} will generate for each NIC a random *MAC address*, so that your VM is | |
293 | addressable on Ethernet networks. | |
294 | ||
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295 | The NIC you added to the VM can follow one of two differents models: |
296 | ||
297 | * in the default *Bridged mode* each virtual NIC is backed on the host by a | |
298 | _tap device_, ( a software loopback device simulating an Ethernet NIC ). This | |
299 | tap device is added to a bridge, by default vmbr0 in {pve}. In this mode, VMs | |
300 | have direct access to the Ethernet LAN on which the host is located. | |
301 | * in the alternative *NAT mode*, each virtual NIC will only communicate with | |
302 | the Qemu user networking stack, where a builting router and DHCP server can | |
303 | provide network access. This built-in DHCP will serve adresses in the private | |
304 | 10.0.2.0/24 range. The NAT mode is much slower than the bridged mode, and | |
305 | should only be used for testing. | |
306 | ||
307 | You can also skip adding a network device when creating a VM by selecting *No | |
308 | network device*. | |
309 | ||
310 | .Multiqueue | |
1ff7835b | 311 | If you are using the VirtIO driver, you can optionally activate the |
af9c6de1 | 312 | *Multiqueue* option. This option allows the guest OS to process networking |
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313 | packets using multiple virtual CPUs, providing an increase in the total number |
314 | of packets transfered. | |
315 | ||
316 | //http://blog.vmsplice.net/2011/09/qemu-internals-vhost-architecture.html | |
317 | When using the VirtIO driver with {pve}, each NIC network queue is passed to the | |
318 | host kernel, where the queue will be processed by a kernel thread spawn by the | |
319 | vhost driver. With this option activated, it is possible to pass _multiple_ | |
320 | network queues to the host kernel for each NIC. | |
321 | ||
322 | //https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Virtualization_Tuning_and_Optimization_Guide/sect-Virtualization_Tuning_Optimization_Guide-Networking-Techniques.html#sect-Virtualization_Tuning_Optimization_Guide-Networking-Multi-queue_virtio-net | |
af9c6de1 | 323 | When using Multiqueue, it is recommended to set it to a value equal |
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324 | to the number of Total Cores of your guest. You also need to set in |
325 | the VM the number of multi-purpose channels on each VirtIO NIC with the ethtool | |
326 | command: | |
327 | ||
328 | `ethtool -L eth0 combined X` | |
329 | ||
330 | where X is the number of the number of vcpus of the VM. | |
331 | ||
af9c6de1 | 332 | You should note that setting the Multiqueue parameter to a value greater |
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333 | than one will increase the CPU load on the host and guest systems as the |
334 | traffic increases. We recommend to set this option only when the VM has to | |
335 | process a great number of incoming connections, such as when the VM is running | |
336 | as a router, reverse proxy or a busy HTTP server doing long polling. | |
337 | ||
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338 | USB Passthrough |
339 | ~~~~~~~~~~~~~~~ | |
340 | There are two different types of USB passthrough devices: | |
341 | ||
342 | * Host USB passtrough | |
343 | * SPICE USB passthrough | |
344 | ||
345 | Host USB passthrough works by giving a VM a USB device of the host. | |
346 | This can either be done via the vendor- and product-id, or | |
347 | via the host bus and port. | |
348 | ||
349 | The vendor/product-id looks like this: *0123:abcd*, | |
350 | where *0123* is the id of the vendor, and *abcd* is the id | |
351 | of the product, meaning two pieces of the same usb device | |
352 | have the same id. | |
353 | ||
354 | The bus/port looks like this: *1-2.3.4*, where *1* is the bus | |
355 | and *2.3.4* is the port path. This represents the physical | |
356 | ports of your host (depending of the internal order of the | |
357 | usb controllers). | |
358 | ||
359 | If a device is present in a VM configuration when the VM starts up, | |
360 | but the device is not present in the host, the VM can boot without problems. | |
361 | As soon as the device/port ist available in the host, it gets passed through. | |
362 | ||
363 | WARNING: Using this kind of USB passthrough, means that you cannot move | |
364 | a VM online to another host, since the hardware is only available | |
365 | on the host the VM is currently residing. | |
366 | ||
367 | The second type of passthrough is SPICE USB passthrough. This is useful | |
368 | if you use a SPICE client which supports it. If you add a SPICE USB port | |
369 | to your VM, you can passthrough a USB device from where your SPICE client is, | |
370 | directly to the VM (for example an input device or hardware dongle). | |
371 | ||
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372 | BIOS and UEFI |
373 | ~~~~~~~~~~~~~ | |
374 | ||
375 | In order to properly emulate a computer, QEMU needs to use a firmware. | |
376 | By default QEMU uses *SeaBIOS* for this, which is an open-source, x86 BIOS | |
377 | implementation. SeaBIOS is a good choice for most standard setups. | |
378 | ||
379 | There are, however, some scenarios in which a BIOS is not a good firmware | |
380 | to boot from, e.g. if you want to do VGA passthrough. footnote:[Alex Williamson has a very good blog entry about this. | |
381 | http://vfio.blogspot.co.at/2014/08/primary-graphics-assignment-without-vga.html] | |
382 | In such cases, you should rather use *OVMF*, which is an open-source UEFI implemenation. footnote:[See the OVMF Project http://www.tianocore.org/ovmf/] | |
383 | ||
384 | If you want to use OVMF, there are several things to consider: | |
385 | ||
386 | In order to save things like the *boot order*, there needs to be an EFI Disk. | |
387 | This disk will be included in backups and snapshots, and there can only be one. | |
388 | ||
389 | You can create such a disk with the following command: | |
390 | ||
391 | qm set <vmid> -efidisk0 <storage>:1,format=<format> | |
392 | ||
393 | Where *<storage>* is the storage where you want to have the disk, and | |
394 | *<format>* is a format which the storage supports. Alternatively, you can | |
395 | create such a disk through the web interface with 'Add' -> 'EFI Disk' in the | |
396 | hardware section of a VM. | |
397 | ||
398 | When using OVMF with a virtual display (without VGA passthrough), | |
399 | you need to set the client resolution in the OVMF menu(which you can reach | |
400 | with a press of the ESC button during boot), or you have to choose | |
401 | SPICE as the display type. | |
402 | ||
403 | ||
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404 | Managing Virtual Machines with 'qm' |
405 | ------------------------------------ | |
f69cfd23 | 406 | |
dd042288 | 407 | qm is the tool to manage Qemu/Kvm virtual machines on {pve}. You can |
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408 | create and destroy virtual machines, and control execution |
409 | (start/stop/suspend/resume). Besides that, you can use qm to set | |
410 | parameters in the associated config file. It is also possible to | |
411 | create and delete virtual disks. | |
412 | ||
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413 | CLI Usage Examples |
414 | ~~~~~~~~~~~~~~~~~~ | |
415 | ||
416 | Create a new VM with 4 GB IDE disk. | |
417 | ||
418 | qm create 300 -ide0 4 -net0 e1000 -cdrom proxmox-mailgateway_2.1.iso | |
419 | ||
420 | Start the new VM | |
421 | ||
422 | qm start 300 | |
423 | ||
424 | Send a shutdown request, then wait until the VM is stopped. | |
425 | ||
426 | qm shutdown 300 && qm wait 300 | |
427 | ||
428 | Same as above, but only wait for 40 seconds. | |
429 | ||
430 | qm shutdown 300 && qm wait 300 -timeout 40 | |
431 | ||
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432 | Configuration |
433 | ------------- | |
434 | ||
435 | All configuration files consists of lines in the form | |
436 | ||
437 | PARAMETER: value | |
438 | ||
871e1fd6 | 439 | Configuration files are stored inside the Proxmox cluster file |
c4cba5d7 | 440 | system, and can be accessed at '/etc/pve/qemu-server/<VMID>.conf'. |
f69cfd23 | 441 | |
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442 | Options |
443 | ~~~~~~~ | |
444 | ||
445 | include::qm.conf.5-opts.adoc[] | |
446 | ||
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447 | |
448 | Locks | |
449 | ----- | |
450 | ||
871e1fd6 FG |
451 | Online migrations and backups ('vzdump') set a lock to prevent incompatible |
452 | concurrent actions on the affected VMs. Sometimes you need to remove such a | |
453 | lock manually (e.g., after a power failure). | |
f69cfd23 DM |
454 | |
455 | qm unlock <vmid> | |
456 | ||
f69cfd23 DM |
457 | |
458 | ifdef::manvolnum[] | |
459 | include::pve-copyright.adoc[] | |
460 | endif::manvolnum[] |