71696cc66c
OOB documentation is spread over qmp-spec.txt sections 2.2.1
Capabilities and 2.3 Issuing Commands. The amount of detail is a bit
distracting there. Move the meat of the matter to new section 2.3.1
Out of band execution.
Throw in a few other improvements while there:
* 2.2 Server Greeting: Drop advice to search entire capabilities
array; should be obvious.
* 3. QMP Examples
- 3.1 Server Greeting: Update greeting to the one we expect for the
release. Now shows capability "oob". Update qmp-intro.txt
likewise.
- 3.2 Capabilities negotiation: Show client accepting capability
"oob".
- 3.7 Out-of-band execution: New.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180703085358.13941-4-armbru@redhat.com>
[Whitespace tidied up]
89 lines
2.1 KiB
Plaintext
89 lines
2.1 KiB
Plaintext
QEMU Machine Protocol
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=====================
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Introduction
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------------
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The QEMU Machine Protocol (QMP) allows applications to operate a
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QEMU instance.
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QMP is JSON[1] based and features the following:
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- Lightweight, text-based, easy to parse data format
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- Asynchronous messages support (ie. events)
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- Capabilities Negotiation
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For detailed information on QMP's usage, please, refer to the following files:
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o qmp-spec.txt QEMU Machine Protocol current specification
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o qemu-qmp-ref.html QEMU QMP commands and events (auto-generated at build-time)
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[1] https://www.json.org
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Usage
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-----
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You can use the -qmp option to enable QMP. For example, the following
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makes QMP available on localhost port 4444:
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$ qemu [...] -qmp tcp:localhost:4444,server,nowait
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However, for more flexibility and to make use of more options, the -mon
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command-line option should be used. For instance, the following example
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creates one HMP instance (human monitor) on stdio and one QMP instance
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on localhost port 4444:
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$ qemu [...] -chardev stdio,id=mon0 -mon chardev=mon0,mode=readline \
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-chardev socket,id=mon1,host=localhost,port=4444,server,nowait \
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-mon chardev=mon1,mode=control,pretty=on
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Please, refer to QEMU's manpage for more information.
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Simple Testing
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--------------
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To manually test QMP one can connect with telnet and issue commands by hand:
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$ telnet localhost 4444
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Trying 127.0.0.1...
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Connected to localhost.
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Escape character is '^]'.
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{
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"QMP": {
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"version": {
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"qemu": {
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"micro": 0,
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"minor": 0,
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"major": 3
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},
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"package": "v3.0.0"
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},
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"capabilities": [
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"oob"
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]
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}
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}
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{ "execute": "qmp_capabilities" }
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{
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"return": {
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}
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}
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{ "execute": "query-status" }
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{
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"return": {
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"status": "prelaunch",
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"singlestep": false,
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"running": false
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}
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}
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Please refer to docs/interop/qemu-qmp-ref.* for a complete command
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reference, generated from qapi/qapi-schema.json.
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QMP wiki page
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-------------
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https://wiki.qemu.org/QMP
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