Commit Graph

194 Commits

Author SHA1 Message Date
Michal Privoznik
adb99a05b1 storage: Support different wiping algorithms
Currently, we support only filling a volume with zeroes on wiping.
However, it is not enough as data might still be readable by
experienced and equipped attacker. Many technical papers have been
written, therefore we should support other wiping algorithms.
2012-01-26 13:59:30 +01:00
Eric Blake
7fb22418ff docs: fix virsh man page
Typo introduced in commit 4e9953a, and remained in 6fba577.

* tools/virsh.pod (snapshot-create): Fix pod error.
2012-01-25 22:20:18 -07:00
Michal Privoznik
6fba577e50 virsh: Expose new VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE flag
to cmdSnapshotCreate and cmdSnapshotCreateAs.
2012-01-25 10:59:41 +01:00
Daniel P. Berrange
17cfff6f17 Allow choice of shutdown method via virsh
Extend the 'shutdown' and 'reboot' methods so that they both
accept a new argument

    --mode acpi|agent

* tools/virsh.c: New args for shutdown/reboot
* tools/virsh.pod: Document new args
2012-01-24 12:19:51 +01:00
Taku Izumi
a3de9829d8 virsh: let domif-{get,set}link take target name
Other virsh domifXXX commands can accept target name
as a parameter to specify interface. From viewpoint of
consistency, virsh domif-getlink command should accept
target name as a parameter. This patch achieves this.

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
2012-01-20 16:53:36 -07:00
Osier Yang
5b4071333b virsh: Two new fields for command domblklist
Disk "type" and "device" are generally interesting stuff the
user may want to known, too. To not break any scripts which
parsed the output field, a new option "--details" is introduced
to output the two introduced fields.
2012-01-13 18:03:12 +08:00
Osier Yang
74e701f8e5 virsh: New command print summary of all virtual interfaces
Just like command "domblklist", the command extracts "type",
"source", "target", "model", and "MAC" of all virtual interfaces
from domain XML (live or persistent).
2012-01-12 17:42:02 +08:00
Shradha Shah
52d064f42d Added new option to virsh net-dumpxml called --inactive
The above option helps to differentiate between implicit and explicit
interface pools.
2012-01-11 13:15:09 -07:00
Eric Blake
4e9953a426 snapshot: allow reuse of existing files in disk snapshot
When disk snapshots were first implemented, libvirt blindly refused
to allow an external snapshot destination that already exists, since
qemu will blindly overwrite the contents of that file during the
snapshot_blkdev monitor command, and we don't like a default of
data loss by default.  But VDSM has a scenario where NFS permissions
are intentionally set so that the destination file can only be
created by the management machine, and not the machine where the
guest is running, so that libvirt will necessarily see the destination
file already existing; adding a flag will allow VDSM to force the file
reuse without libvirt complaining of possible data loss.

https://bugzilla.redhat.com/show_bug.cgi?id=767104

* include/libvirt/libvirt.h.in (virDomainSnapshotCreateFlags): Add
VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.  Add
note about partial failure.
* tools/virsh.c (cmdSnapshotCreate, cmdSnapshotCreateAs): Add new
flag.
* tools/virsh.pod (snapshot-create, snapshot-create-as): Document
it.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDiskPrepare)
(qemuDomainSnapshotCreateXML): Implement the new flag.
2012-01-10 11:53:23 -07:00
Hu Tao
b2310b2913 domiftune: Enable the virDomain{S,G}etInterfaceParameters in virsh
Add a new command domiftune to get/set interface parameters.

* tools/virsh.c: implement the new command
* tools/virsh.pod: documentation of the new command
2011-12-29 18:29:25 +08:00
Satoru SATOH
1f24ddf6bf docs: Move 'echo' command description into the generic commands section
Virsh's echo command looks not having any relations with domains and its
description should go into the generic commands section instead of the
domain commands section (current).
2011-12-26 11:29:23 +08:00
Satoru SATOH
b2c545bf80 docs: Move 'send-key' command description into the domain commands section
Virsh's send-key command manipulates domains and its description should
go into the domain commands section instead of generic commands section
(current).
2011-12-26 11:21:24 +08:00
Michal Privoznik
74ad69b708 virsh: Use vshWatchJob in cmdManagedSave
This patch alters saving code, so we can report progress
and allow cancel via ^C.
2011-12-22 11:31:51 +01:00
Michal Privoznik
6e4c540d28 virsh: Use vshWatchJob in cmdSave
This patch alters saving code, so we can report progress
and allow cancel via ^C.
2011-12-22 11:31:24 +01:00
Michal Privoznik
5ccc7f6488 virsh: Use vshWatchJob in cmdDump
This patch alters dumping code, so we can report progress
and allow cancel via ^C.
2011-12-22 11:11:28 +01:00
Alex Jia
fbdfda14a1 docs: improve virsh domxml-*-native command docs
* tools/virsh.pod: improve virsh man page for domxml-from-native and
domxml-to-native commands.

Signed-off-by: Alex Jia <ajia@redhat.com>
2011-12-20 14:08:41 -07:00
Hu Tao
9da9a3b047 add new command numatune to virsh
add new command numatune to virsh to get/set numa parameters
2011-12-20 11:23:46 -07:00
Peter Krempa
3bb6bcfc79 virsh: Add option to undefine storage with domains
Add an option for virsh undefine command, to remove associated storage
volumes while undefining a domain. This patch allows the user to remove
associated (libvirt managed ) storage volumes while undefining a domain.

The new option --storage for the undefine command takes a string
argument that consists of comma separated list of target or source path
of volumes to be undefined. Volumes are removed after the domain has
been successfully undefined,

If a volume is not part of a storage pool, the user is warned to remove
the volume in question himself.

Option --wipe-storage may be specified along with this, that ensures
the image is wiped before removing.

Option --remove-all-storage enables the user to remove all storage. The
name is chosen long as the users should be aware what they're about to
do.
2011-12-16 11:42:12 +01:00
KAMEZAWA Hiroyuki
65aefae1a8 virsh: support multifunction in attach-disk
PCI <address...> can be specified by attach-disk but multifunction cannot
be specified. Add --multifunction support.
2011-12-13 16:15:20 -07:00
Eric Blake
972f7e6e49 docs: tweak 'virsh edit' wording
I was wondering why 'virsh edit' didn't support the same
'--inactive' option as 'virsh dumpxml'; reading the source
code showed that --inactive was already implied, and that
the only way to alter a running guest rather than affecting
next boot is by hot-plugging individual devices, or by
something complex like saving the guest and modifying the
save image.

* tools/virsh.pod (define, edit): Mention behavior when guest is
already running.
2011-12-13 15:58:43 -07:00
Michal Privoznik
7a79648532 virsh: Allow other escape characters for console
Currently virsh supports only ^] as escape character for console.
However, some users might want to use something else. This patch
creates such ability by specifying '-e' switch on virsh command
line.
2011-12-01 09:51:25 +01:00
Eric Blake
22cf6d46f4 qemu: amend existing table of device weights
Prior to this patch, for a running dom, the commands:

$ virsh blkiotune dom --device-weights /dev/sda,502,/dev/sdb,498
$ virsh blkiotune dom --device-weights /dev/sda,503
$ virsh blkiotune dom
weight         : 500
device_weight  : /dev/sda,503

claim that /dev/sdb no longer has a non-default weight, but
directly querying cgroups says otherwise:

$ cat /cgroup/blkio/libvirt/qemu/dom/blkio.weight_device
8:0     503
8:16    498

After this patch, an explicit 0 is required to remove a device path
from the XML, and omitting a device path that was previously
specified leaves that device path untouched in the XML, to match
cgroups behavior.

* src/qemu/qemu_driver.c (parseBlkioWeightDeviceStr): Rename...
(qemuDomainParseDeviceWeightStr): ...and use correct type.
(qemuDomainSetBlkioParameters): After parsing string, modify
rather than replacing existing table.
* tools/virsh.pod (blkiotune): Tweak wording.
2011-11-30 12:18:18 -07:00
Lei Li
e9bd9a0809 Enable the blkdeviotune command in virsh
Support virsh command blkdeviotune. Can set or query a block disk
I/O throttle setting.

Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2011-11-30 11:36:11 -07:00
Hu Tao
6ac81c8ec8 blkiotune: add interface for blkiotune.device_weight
This adds per-device weights to <blkiotune>.  Note that the
cgroups implementation only supports weights per block device,
and not per-file within the device; hence this option must be
global to the domain definition rather than tied to individual
<devices>/<disk> entries:

<domain ...>
  <blkiotune>
    <device>
      <path>/path/to/block</path>
      <weight>1000</weight>
    </device>
  </blkiotune>
..

This patch also adds a parameter --device-weights to virsh command
blkiotune for setting/getting blkiotune.weight_device for any
hypervisor that supports it.  All <device> entries under
<blkiotune> are concatenated into a single string attribute under
virDomain{Get,Set}BlkioParameters, named "device_weight".

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2011-11-29 12:26:21 -07:00
Osier Yang
72908c7403 block_resize: Expose the new API to virsh 2011-11-29 21:45:22 +08:00
Jiri Denemark
6b84ee3370 virsh: Fix typos in man page 2011-11-29 14:16:42 +01:00
Srivatsa S. Bhat
34401a8b42 Add virsh command to initiate suspend on the host
Add a new command 'nodesuspend' to perform a timed suspend on the host.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
2011-11-29 17:29:17 +08:00
Laine Stump
1ae8eed1b4 virsh: add iface-bridge and iface-unbridge commands
One of the top questions by libvirt users is how to create a host
bridge device so that guests can be directly on the physical
network. There are several example documents that explain how to do
this manually, but following them often results in confusion and
failure. virt-manager does a good job of creating a bridge based on an
existing network device, but not everyone wants to use virt-manager.

This patch adds a new command, iface-bridge that makes it just about
as simple as possible to create a new bridge device based on an
existing ethernet/vlan/bond device (including associating IP
configuration with the bridge rather than the now-attached device),
and start that new bridge up ready for action, eg:

    virsh iface-bridge eth0 br0

For symmetry's sake, it also adds a command to remove a device from a
bridge, restoring the IP config to the now-unattached device:

    virsh iface-unbridge br0

(I had a short debate about whether to do "iface-unbridge eth0"
instead, but that would involve searching through all bridge devices
for the one that contained eth0, which seems like a bit too much
trouble).

NOTE: These two commands require that the netcf library be available
on the host. Hopefully this will provide some extra incentive for
people using suse, debian, ubuntu, and other similar systems to polish
up (and push downstream) the ports to those distros recently pushed to
the upstream netcf repo by Dan Berrange. Anyone interested in helping
with that effort in any way should join the netcf-devel mailing list
(subscription info at
https://fedorahosted.org/mailman/listinfo/netcf-devel)

During creation of the bridge, it's possible to specify whether or not
the STP protocol should be started up on the bridge and, if so, how
many seconds the bridge should squelch traffic from newly added
devices while learning new topology (defaults are stp='on' and
delay='0', which seems to usually work best for bridges used in the
context of libvirt guests).

There is also an option to not immediately start the bridge (and a
similar option to not immediately start the un-attached device after
destroying the bridge. Default is to start the new device, because in
the case of iface-unbridge not starting is strongly discouraged as it
will leave the system with no network connectivity on that interface
(because it's necessary to destroy/undefine the bridge device before
the unattached device can be defined), and it seemed better to make
the option for iface-bridge behave consistently.

NOTE TO THOSE TRYING THESE COMMANDS FOR THE FIRST TIME: to guard
against any "unexpected" change to configuration, it is advisable to
issue an "virsh iface-begin" command before starting any interface
config changes, and "virsh iface-commit" only after you've verified
that everything is working as you expect. If something goes wrong,
you can always run "virsh iface-rollback" or reboot the system (which
should automatically do iface-rollback).

Aside from adding the code for these two functions, and the two
entries into the command table, the only other change to virsh.c was
to add the option name to vshCommandOptInterfaceBy(), because the
iface-unbridge command names its interface option as "bridge".

virsh.pod has also been updated with short descriptions of these two
new commands.
2011-11-16 15:56:45 -05:00
Eric Blake
10d3272ec3 docs: document managed=yes of hostdev passthrough
Clarify some of the effects of managed passthrough <hostdev> devices;
with recent changes (commit d093547), a nodedev-reattach is only needed
to pair up to an explicit nodedev-dettach (but beware that older
virt-manager has a bug where it uses explicit nodedev-dettach under the
hood when using the gui to hotplug a hostdev device).

* docs/formatdomain.html.in: Mention reattach.
* tools/virsh.pod (nodedev): Mention managed mode.
2011-10-20 14:19:04 -06:00
Hu Tao
7b2723c5c1 support setting bandwidth from virsh attach-interface
Adds two options, inbound and outbound, to attach-interface to set
bandwidth when attaching interfaces
2011-10-20 10:31:50 +02:00
Michal Privoznik
4dadfe59d5 virDomainCoreDump: Introduce VIR_DUMP_RESET flag
This flag is intended to allow user to do so called system reset
after dump, instead of sending ACPI reboot event.
2011-10-13 09:32:27 +02:00
Eric Blake
8b6d1a2068 snapshot: add API for filtering by leaves
Counterpart to --roots.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_LIST_LEAVES):
New flag.
* src/libvirt.c (virDomainSnapshotNum, virDomainSnapshotListNames)
(virDomainSnapshotNumChildren)
(virDomainSnapshotListChildrenNames): Document it.
* tools/virsh.c (cmdSnapshotList): Expose it.
* tools/virsh.pod (snapshot-list): Document --leaves.
2011-10-12 16:03:19 -06:00
Eric Blake
b77b203cac snapshot: virsh shorthand for operating on current snap
Rather than having to do:

$ virsh snapshot-revert dom $(virsh snapshot-current dom --name)

I thought it would be nice to do:

$ virsh snapshot-revert dom --current

I didn't add 'virsh snapshot-dumpxml --current' since we already have
'virsh snapshot-current' for the same task.  snapshot-list accepted
a name but did not require it, and that remains the case, with
--current serving in place of that name.  For all other commands,
name used to be required, and can now be replaced by --current;
I intentionally made it so that omitting both --current and a name
is an error (having the absence of a name imply --current seems
just a bit too magic, so --current must be explicit).  I also had
to keep snapshot-edit backwards-compatible, as the only command
that already had a --current argument alongside a name, which still
works to both edit a named snapshot and make it current.

* tools/virsh.c (vshLookupSnapshot): New helper function.
(cmdSnapshotEdit, cmdSnapshotList, cmdSnapshotParent)
(cmdSnapshotDelete, cmdDomainSnapshotRevert): Use it, adding an
option where needed.
* tools/virsh.pod (snapshot-delete, snapshot-edit)
(snapshot-list, snapshot-parent, snapshot-revert): Document
use of --current.
(snapshot-dumpxml): Mention alternative.
2011-10-11 16:38:48 -06:00
Eric Blake
fe383bb541 snapshot: virsh snapshot-list and children
Sometimes, we only care about one branch of the snapshot hierarchy.
Make it easier to list a single branch, by using the new APIs.

Technically, I could emulate these new virsh options on old servers
by doing a complete dump, then scraping xml to filter out just the
snapshots that I care about, but I didn't want to do that in this patch.

* tools/virsh.c (cmdSnapshotList): Add --from, --descendants.
* tools/virsh.pod (snapshot-list): Document them.
2011-10-10 17:11:05 -06:00
Eric Blake
bab4f31c78 snapshot: avoid accidental renames with snapshot-edit
I was a bit surprised that 'virsh snapshot-edit dom name' silently
allowed me to clone things, while still telling me the old name,
especially since other commands like 'virsh edit dom' reject rename
attempts (*).  This fixes things to be more explicit (**).

(*) Technically, 'virsh edit dom' relies on virDomainDefineXML
behavior, which rejects attempts to mix a new name with existing
uuid or new uuid with existing name, but you can create a new
domain by changing both uuid and name.  On the other hand, while
snapshot-edit --clone is a true clone, creating a new domain
would also have to decide whether to clone snapshot metadata,
managed save, and any other secondary data related to the domain.
Domain renames are not trivial either.

(**) Renaming or creating a clone is still a risky proposition -
for offline snapshots and system checkpoints, if the new name
does not match an actual name recorded in the qcow2 internal
snapshots, then you cannot revert to the new checkpoint.  But it
is assumed that anyone using the new virsh flags knows what they
are doing, and can deal with the fallout caused by a rename/clone;
that is, we can't completely prevent a user from shooting
themselves in the foot, so much as we are making the default
action less risky.

* tools/virsh.c (cmdSnapshotEdit): Add --rename, --clone.
* tools/virsh.pod (snapshot-edit): Document them.
2011-10-10 11:56:05 -06:00
Eric Blake
3c797404a5 snapshot: add REVERT_FORCE to API
Although reverting to a snapshot is a form of data loss, this is
normally expected.  However, there are two cases where additional
surprises (failure to run the reverted state, or a break in
connectivity to the domain) can come into play.  Requiring extra
acknowledgment in these cases will make it less likely that
someone can get into an unrecoverable state due to a default revert.

Also create a new error code, so users can distinguish when forcing
would make a difference, rather than having to blindly request force.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_REVERT_FORCE):
New flag.
* src/libvirt.c (virDomainRevertToSnapshot): Document it.
* include/libvirt/virterror.h (VIR_ERR_SNAPSHOT_REVERT_RISKY): New
error value.
* src/util/virterror.c (virErrorMsg): Implement it.
* tools/virsh.c (cmdDomainSnapshotRevert): Add --force to virsh.
* tools/virsh.pod (snapshot-revert): Document it.
2011-10-05 11:33:36 -06:00
Xu He Jie
0ec9a8c2f2 virsh: Add 'reset' command for virsh
Signed-off-by: Xu He Jie <xuhj@linux.vnet.ibm.com>
2011-09-29 07:04:14 -06:00
Daniel Veillard
dd09da70f2 virsh: describe attach-interface parameter target
This patch is based on a improvement suggested by Kazuhiro Kikuchi
of Fujitsu, it gives a description of the target parameter for that
command

* tools/virsh.pod: add description for target parameter of
  attach-interface
2011-09-29 08:48:14 +08:00
Daniel Veillard
0c92e1428f virsh: update man page for cpu_shares parameter
The man page suggest that the cpu_shares parameter of schedinfo
allows values 0-262144, but the kernel remaps values 0 and 1 to
the minimum 2, just document that behaviour:

[root@test ~]# cat /cgroup/cpu/libvirt/qemu/cpu.shares
1024
[root@test ~]# echo 0 > /cgroup/cpu/libvirt/qemu/cpu.shares
[root@test ~]# cat /cgroup/cpu/libvirt/qemu/cpu.shares
2
[root@test ~]# echo 1 > /cgroup/cpu/libvirt/qemu/cpu.shares
[root@test ~]# cat /cgroup/cpu/libvirt/qemu/cpu.shares
2
[root@test ~]#

* tools/virsh.pod: update description of the cpu_shares parameter
  to indicate the values 0 and 1 are automatically changed by the
  kernel to minimal value 2
2011-09-29 08:48:03 +08:00
Eric Blake
1cf0e3db8b snapshot: add virsh snapshot-list --tree
Reuse the tree listing of nodedev-list, coupled with the new helper
function to efficiently grab snapshot parent names, to produce
tree output for a snapshot hierarchy.  For example:

$ virsh snapshot-list dom --tree
root1
 |
  +- sibling1
  +- sibling2
  |   |
  |   +- grandchild
  |
  +- sibling3

root2
 |
  +- child

* tools/virsh.c (cmdSnapshotList): Add --tree.
* tools/virsh.pod (snapshot-list): Document it.
2011-09-28 09:54:57 -06:00
Eric Blake
beeab55908 docs: document virsh nodedev-* commands
This section of the man page was completely missing; I stumbled on
it when I had no clue that I had to use nodedev-reattach after
I was done playing with <hostdev> device passthrough to one of my
guests.

* tools/virsh.pod (NODEDEV COMMANDS): New section.
(attach-device, detach-device): Add cross-references.
2011-09-28 09:17:02 -06:00
Eric Blake
63b2edc81c snapshot: fix man page typos
pod2man from perl-5.8.8 (RHEL 5) errors out on ill-formed POD:

*** ERROR: unterminated I<...> at line 1114 in file virsh.pod
*** ERROR: unterminated I<...> at line 1851 in file virsh.pod

Newer pod2man appears to be more tolerant (which is a shame,
because it meant that this error is harder to detect).

* tools/virsh.pod (undefine, snapshot-current): Add missing >.
2011-09-27 17:35:21 -06:00
Jiri Denemark
2c1a3dd878 virsh: Better document --copy-storage migrate options
Both --copy-storage-{all,inc} options require disk images to be present
on destination host.
2011-09-27 15:44:08 +02:00
Jiri Denemark
d82ce38415 virsh: Enhance documentation of commands starting jobs
Some virsh commands start a (long-running) job that can be monitored
using domjobinfo and aborted with domjobabort. Let's be explicit about
this in virsh man page.
2011-09-27 15:41:55 +02:00
Oskari Saarenmaa
f887334dcf Add unsafe cache mode support for disk driver
QEMU 0.13 introduced cache=unsafe for -drive, this patch exposes
it in the libvirt layer.

  * Introduced a new QEMU capability flag ($prefix_CACHE_UNSAFE),
    as even if $prefix_CACHE_V2 is set, we can't know if unsafe
    is supported.

  * Improved the reliability of qemu cache type detection.
2011-09-23 08:29:57 -06:00
Peter Krempa
c4111bd0d9 virsh: Improve virsh manual for virsh memtune command
Commit 0a22f54 added --min-guarantee option for the memtune command.
This option is supported only by the ESX hypervisor. This patch adds a
statement about this fact, to prevent user confusion.

This patch also adds explanation how to clear/set to unlimited the
memory tunables. (documments the -1 value).
2011-09-22 11:07:45 -06:00
Peter Krempa
2ad83bf448 virsh: doc: Fix supported driver types for attach-disk command
Virsh man page lists driver types to be used with attach-device
command, but does not specify that those are usable only with the XEN
Hypervisor.

This patch adds statement, that those options specified are applicable
only on the Xen hypervisor and adds option usable with qemu emulator.

This patch also changes type of error returned by QEMU driver if the
user specifies incompatible driver type from VIR_ERR_INTERNAL_ERROR to
VIR_ERR_CONFIG_UNSUPPORTED.
2011-09-19 16:54:13 -06:00
Peter Krempa
619077b9eb virsh: Add more human-friendly output of domblkstat command
Users of virsh complain that output of the domblkstat command
is not intuitive enough. This patch adds explanation of fields
returned by this command to the help section for domblkstat and
the man page of virsh. Also a switch --human is added for
domblkstat that prints the fields with more descriptive
texts.

This patch also changes sequence of the output fields and their
names back to the order and spelling established by previous
versions of virsh to maintain compatibility with scripts.

Example of ordered and "translated" output:

PRE-patch:

virsh # domblkstat 1 vda
vda wr_bytes 5170176
vda wr_operations 511
vda rd_bytes 82815488
vda rd_operations 3726

POST-patch:

virsh # domblkstat 1 vda
vda rd_req 3726
vda rd_bytes 82815488
vda wr_req 478
vda wr_bytes 4965376

Example of human readable output:

virsh # domblkstat 1 vda --human
Device: vda
 number of read operations:      3726
 number of read bytes:           82815488
 number of write operations:     478
 number of bytes written:        4965376

https://bugzilla.redhat.com/show_bug.cgi?id=731656
2011-09-19 14:24:08 -06:00
Peter Krempa
4d4430e125 doc: Add statment about permissions needed to do a core dump
Documentation did not specify, that some permissions are required on
target path for coredump for the user running the hypervisor.

Diff to v1:
- reword statements
2011-09-16 20:40:21 +08:00
Eric Blake
85d2810823 snapshot: tweak snapshot-create-as diskspec docs
With this patch, it is hopefully a bit more obvious that for
snapshot-create-as, a literal '--diskspec' is mandatory if name
or description was omitted, but optional if all earlier options
were provided.

These all denote two diskspecs and a description:
virsh snapshot-create-as dom name desc vda vdb
virsh snapshot-create-as dom name desc --diskspec vda --diskspec vdb
virsh snapshot-create-as dom name desc --diskspec vda vdb
virsh snapshot-create-as dom name desc vda --diskspec vdb
virsh snapshot-create-as dom --diskspec vda --diskspec vdb name desc

This gives two diskspecs but no description:
virsh snapshot-create-as dom name --diskspec vda --diskspec vdb

And this treats 'vda' as the description, with only one diskspec:
virsh snapshot-create-as dom name vda vdb

The help output now shows:
    snapshot-create-as <domain> [<name>] [<description>] [--print-xml] [--no-metadata] [--halt] [--disk-only] [[--diskspec] <string>]...

I also checked the help output for echo and send-key, which are two
other variants of argv commands.

* tools/virsh.pod (snapshot-create-as): Document when a literal
--diskspec must preceed a diskspec argument.
* tools/virsh.c (vshCmddefHelp): Update help output for argv when
naming the option is useful.
(vshCmddefGetData): Fix logic on when argv was seen.
* tests/virsh-optparse: Add tests to avoid regressions.
2011-09-15 16:18:12 -06:00