Commit fad5cd2108 introduced option to
display domain's title in the list command output. There was a mistake
in the virsh man page example for this command stating --note instead of
--title.
When blkdeviotune was first committed in 0.9.8, we had the limitation
that setting one value reset all others. But bytes and iops should
be relatively independent. Furthermore, setting tuning values on
a live domain followed by dumpxml did not output the new settings.
* src/qemu/qemu_driver.c (qemuDiskPathToAlias): Add parameter, and
update callers.
(qemuDomainSetBlockIoTune): Don't lose previous unrelated
settings. Make live changes reflect to dumpxml output.
* tools/virsh.pod (blkdeviotune): Update documentation.
This patch adds a new command "desc" to show and modify titles and
description for the domains using the new API.
This patch also adds a new flag for the "list" command to show titles in
the domain list, to allow easy identification of VMs by storing a short
description.
Example:
virsh # list --title
Id Name State Title
-----------------------------------------------
0 Domain-0 running Mailserver 1
2 fedora paused
Add a new function to allow changing of capacity of storage volumes.
Plan out several flags, even if not all of them will be implemented
up front.
Expose the new command via 'virsh vol-resize'.
Signed-off-by: Eric Blake <eblake@redhat.com>
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.
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
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>
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.
Just like command "domblklist", the command extracts "type",
"source", "target", "model", and "MAC" of all virtual interfaces
from domain XML (live or persistent).
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.
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
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).
Virsh's send-key command manipulates domains and its description should
go into the domain commands section instead of generic commands section
(current).
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.
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.
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.
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.
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>
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>
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.
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.
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.
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.
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.
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.
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
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
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.
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.
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 >.
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.
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.
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).
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.
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
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
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.
Two new commands are added to virsh that wrap usage of
virDomainUpdateDeviceFlags for changing link state of domain's network
interfaces. These wrappers extract network devices's xml configuration
and modify the link state for easy manipulation from an user's perspective.
- domif-setlink - set link state of a domains virtual network interface
- domif-getlink - get link state
* tools/virsh.c - Add functionality to virsh
* tools/virsh.pod - Manpage documentation
Expose the disk-only flag through virsh. Additionally, make
virsh snapshot-create-as take an arbitrary number of diskspecs,
which can be used to build up the xml for <domainsnapshot>.
* tools/virsh.c (cmdSnapshotCreate): Add --disk-only.
(cmdSnapshotCreateAs): Likewise, and add argv diskspec.
(vshParseSnapshotDiskspec): New helper function.
(vshCmddefGetOption): Allow naming of argv field.
* tools/virsh.pod (snapshot-create, snapshot-create-as): Document
them.
* tests/virsh-optparse: Test snapshot-create-as parsing.
This adds a convenience function to virsh that parses out block
information from the domain xml, making it much easier to see
what strings can be used in all other contexts that demand a
specific block name, especially when given the previous patch
that allows using either target or unique source name.
As an example on a domain with one disk and an empty cdrom drive:
Target Source
-------------------------------------------
vda /var/lib/libvirt/images/fedora_12.img
hdc -
* tools/virsh.c (cmdDomblklist): New function.
* tools/virsh.pod (domblklist): Document it.
I got confused when 'virsh domblkinfo dom disk' required the
path to a disk (which can be ambiguous, since a single file
can back multiple disks), rather than the unambiguous target
device name that I was using in disk snapshots. So, in true
developer fashion, I went for the best of both worlds - all
interfaces that operate on a disk (aka block) now accept
either the target name or the unambiguous path to the backing
file used by the disk.
* src/conf/domain_conf.h (virDomainDiskIndexByName): Add
parameter.
(virDomainDiskPathByName): New prototype.
* src/libvirt_private.syms (domain_conf.h): Export it.
* src/conf/domain_conf.c (virDomainDiskIndexByName): Also allow
searching by path, and decide whether ambiguity is okay.
(virDomainDiskPathByName): New function.
(virDomainDiskRemoveByName, virDomainSnapshotAlignDisks): Update
callers.
* src/qemu/qemu_driver.c (qemudDomainBlockPeek)
(qemuDomainAttachDeviceConfig, qemuDomainUpdateDeviceConfig)
(qemuDomainGetBlockInfo, qemuDiskPathToAlias): Likewise.
* src/qemu/qemu_process.c (qemuProcessFindDomainDiskByPath):
Likewise.
* src/libxl/libxl_driver.c (libxlDomainAttachDeviceDiskLive)
(libxlDomainDetachDeviceDiskLive, libxlDomainAttachDeviceConfig)
(libxlDomainUpdateDeviceConfig): Likewise.
* src/uml/uml_driver.c (umlDomainBlockPeek): Likewise.
* src/xen/xend_internal.c (xenDaemonDomainBlockPeek): Likewise.
* docs/formatsnapshot.html.in: Update documentation.
* tools/virsh.pod (domblkstat, domblkinfo): Likewise.
* docs/schemas/domaincommon.rng (diskTarget): Tighten pattern on
disk targets.
* docs/schemas/domainsnapshot.rng (disksnapshot): Update to match.
* tests/domainsnapshotxml2xmlin/disk_snapshot.xml: Update test.
Easy enough to emulate even with older servers.
* tools/virsh.c (cmdSnapshotCreate, cmdSnapshotCreateAs): Add
--halt flag.
(vshSnapshotCreate): Emulate halt when flag is unsupported.
* tools/virsh.pod (snapshot-create, snapshot-create-as): Document
it.
It would technically be possible to have virsh compute the list
of descendants of a given snapshot, then delete those one at
a time. But it's complex, and not worth writing for a first
cut at implementing the new flags.
* tools/virsh.c (cmdSnapshotDelete): Add --children-only,
--metadata.
* tools/virsh.pod (snapshot-delete): Document them.
Similar to 'undefine --managed-save' (commit 83e849c1), we must
assume that the old API is unsafe; however, we cannot emulate
metadata-only deletion on older servers. Additionally, we have
the wrinkle that while virDomainUndefineFlags and managed save
cleanup were introduced in 0.9.4, it wasn't until 0.9.5 that
snapshots block undefine of a domain. Do the best we can given
the server we are talking to.
* tools/virsh.c (cmdUndefine): Add --snapshots-metadata flag.
* tools/virsh.pod (undefine, destroy, shutdown): Document effect
of snapshots.
Wire up the new snapshot creation flags in virsh. For convenience,
teach 'snapshot-current' how to make an existing snapshot become
current (can be used after upgrading to newer libvirt to recover
from the fact that the older libvirt lost track of the current
snapshot after a restart). The snapshot-create-as command is
intentionally not taught --redefine or --current, as this would
imply adding a lot of other options for everything else that can
appear in the <domainsnapshot> xml, but which is normally read-only.
Besides, redefining will usually be done on files created by
snapshot-dumpxml, rather than something built up by hand on the
command line. And now that we can redefine, we can edit.
* tools/virsh.c (cmdSnapshotCreate): Add --redefine, --current,
and --no-metadata.
(cmdSnapshotCreateAs): Add --no-metadata.
(cmdSnapshotCurrent): Add snapshotname to alter current snapshot.
(cmdSnapshotEdit): New command.
* tools/virsh.pod (snapshot-create, snapshot-create-as)
(snapshot-current, snapshot-edit): Document these.
New flag bits are worth exposing via virsh. In the case of
snapshot-list --roots, it's possible to emulate this even when
talking to an older server that lacks the bit; whereas
--metadata requires a newer server.
Although we don't use --security-info yet, the flag is already
documented for other dumpxml operations, and turning it on now
will make it useful when a future patch actually has to honor it.
* tools/virsh.c (cmdSnapshotDumpXML, cmdSnapshotCurrent): Add
--security-info.
(cmdSnapshotList): Add --roots, --metadata.
* tools/virsh.pod (snapshot-dumpxml, snapshot-current)
(snapshot-list): Document these.
Even though I recently added 'virsh snapshot-parent', doing it one
snapshot at a time is painful, so make it possible to expand the
snapshot-list table at once.
* tools/virsh.c (cmdSnapshotList): Add --parent.
* tools/virsh.pod (snapshot-list): Document it.
Pretty straight-forward exposure of new flags. For most commands,
we let the API reject mutually exclusive flags; but for save-image-edit,
we do the sanity check ourselves to avoid looping on flag failure if
the edit cycle is ever enhanced to allow the user to retry an edit
to fix up an xml validation error.
* tools/virsh.c (cmdManagedSave, cmdRestore, cmdSave)
(cmdSaveImageDefine, cmdSaveImageEdit): Add new flags.
* tools/virsh.pod (managedsave, restore, save, save-image-define)
(save-image-edit): Document them.
Newer QEMU introduced cache=directsync for -drive, this patchset
is to expose it in libvirt layer.
* Introduced a new QEMU capability flag ($prefix_CACHE_DIRECTSYNC),
As even $prefix_CACHE_V2 is set, we can't known if directsync
is supported.
The 'virsh man' description of send-key was incomplete and used the
old style (literal 'optional name' instead of '[name]' metasyntax).
Meanwhile, none of the other virsh help texts include examples, so
I moved it out of virsh help and into the man page.
* tools/virsh.pod (send-key): Give better details.
* tools/virsh.c (info_send_key): Drop example from here.
There have been several instances of people having problems with
a broken managed save file, and not aware that they could use
'virsh managedsave-remove dom' to fix things. Making it possible
to do this as part of starting a domain makes the same functionality
easier to find, and one less API call.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_START_FORCE_BOOT): New
flag.
* src/libvirt.c (virDomainCreateWithFlags): Document it.
* src/qemu/qemu_driver.c (qemuDomainObjStart): Alter signature.
(qemuAutostartDomain, qemuDomainStartWithFlags): Update callers.
* tools/virsh.c (cmdStart): Expose it in virsh.
* tools/virsh.pod (start): Document it.
This patch updates the man page about virsh schedinfo command.
- fix typo: 1844674407370955 -> 18446744073709551
- describe the value 0 of vcpu_period and vcpu_quota parameters
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Knowing whether 'virsh start' will resume a saved image or do
a fresh boot is useful enough to expose via 'virsh list'.
Also, translate the state column.
* tools/virsh.c (cmdList): add --managed-save flag
* tools/virsh.pod (list): Document it.
Based on a suggestion by Miklos Vajna.
Call me lazy, but:
virsh qemu-monitor-command dom --hmp info status
is nicer than:
virsh qemu-monitor-command dom --hmp 'info status'
* tools/virsh.c (cmdQemuMonitorCommand): Allow multiple arguments,
for convenience.
Down the road, I want to add virDomainSnapshotGetParent, and use
the new API rather than xml scraping; but this virsh command can
be implemented even without the new API.
* tools/virsh.c (cmdSnapshotParent): New command.
* tools/virsh.pod (snapshot-parent): Document it.
Sometimes, full XML is too much; since most snapshot commands
operate on a snapshot name, there should be an easy way to get
at the current snapshot's name. For example:
virsh snapshot-revert dom `virsh snapshot-current dom --name`
* tools/virsh.c (cmdSnapshotCurrent): Add an option.
* tools/virsh.pod (snapshot-current): Document it.
The description of the list command seemed to suggest that it could
take a set of domains as an argument, which is not correct in the
current HEAD. If virsh list is intended to take a list of domains,
then this patch should be NAK'd and a bug opened against virsh list.
Reported by hachi on #virt
v2:
Change language to include transient domains
Osier pointed out that transient domains are not defined, so what I
had originally proposed wasn't quite correct.
Rename the existing --current flag to the new name --active,
while adding a new flag --current to expose the new
VIR_DOMAIN_AFFECT_CURRENT flag of virDomainGetVcpusFlags.
For backwards compability, the output does not change (even
though the label "current" no longer matches the spelling of
the option that would trigger that number in isolation), and
we accept "--current --live" as an undocumented synonym for
"--active --live" to avoid breaking any existing clients.
* tools/virsh.c (cmdVcpucount): Add --active flag, and rearrange
existing flag handling to expose VIR_DOMAIN_AFFECT_CURRENT support.
* tools/virsh.pod (vcpucount): Document this.
Now you can edit a saved state file even if you forgot to grab
a dumpxml file prior to saving a domain. Plus, in-place editing
feels so much nicer.
* tools/virsh.c (cmdSaveImageDumpxml, cmdSaveImageDefine)
(cmdSaveImageEdit): New commands.
* tools/virsh.pod (save-image-dumpxml, save-image-define)
(save-image-edit): Document them.
Also, migrate was missing documentation for the --xml option
added in commit ec5301cb.
* tools/virsh.c (cmdSave, cmdRestore): Add xml argument.
* tools/virsh.pod (save, restore, migrate): Document it.
Wire up the new flag to several virsh commands. Also, the
'dump' command had undocumented flags.
* tools/virsh.c (cmdSave, cmdManagedSave, cmdDump, cmdStart)
(cmdRestore): Add new flag.
* tools/virsh.pod (save, managedsave, dump, start, restore):
Document flags.
If the domain has managed save image, and --managed-save is
not specified, then it fails with an error telling the user
that a managed save image still exists.
If the domain has managed save image, and --managed-save is
specified, it invokes virDomainUndefineFlags. If
virDomainUndefineFlags fails, then it tries to remove the managed
save image using virDomainManagedSaveRemove first, with
invoking virDomainUndefine following. (For compatibility between
new virsh with this patch and older libvirt without this patch).
Similarly if the domain has no managed save image. See the codes for
detail.
NOTE: Have not removing the codes checking if the domain is running
in function "cmdUndefine", it will go along with qemu driver's fix
(allow to undefine a running domain).
* tools/virsh.c: new column "Managed save" for "cmdDominfo".
* tools/virsh.pod: Update document of "managedsave" to tell one can
use "dominfo" to query whether a domain has any managed save image.
We can make the virsh migrate UI friendlier by supplying the
missing bit automatically instead of erroring out when requesting
--tunnelled without --p2p.
* tools/virsh.c (doMigrate): Make --p2p optional when using
--tunnelled.
* tools/virsh.pod (migrate): Tweak wording accordingly.
"optional" is not a very good meta-syntactic construct in our man
page. I scrubbed this, and additionally improved some documentation
on mutually exclusive options. For example,
[[--live] [--config] | [--current]]
implies a set of optional flags, where within the set you can have
either --current or a choice of 0, 1, or both --live and --config.
* tools/virsh.pod: Use "[name]" rather than "optional name" for
optional arguments.
This adds four options for virsh command attach-disk.
--cache option allows user to specify cache mode of disk device
from virsh command line when attaching a disk device.
--serial option allows user to specify serial string of disk device
from virsh command line when attaching a disk device.
--shareable option allows user to specify whether the disk device is
shareable between domains when attaching a disk device from virsh
command line.
--address option allows user to specify address of disk device when
attaching a disk device.
This patch adds the --current option to "virsh setvcpus"
command. Currently "virsh setvcpus" command supports
"--live" and "--config" , but "--current" option.
From view of consistency, it's reasonable to support
"--current" option too.
When --current is specified, it affects a "current"
domain.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Valid loglevel range for virsh is 0-4. Update virsh man page
accordingly. Also explain virsh ENV variables and values.
Signed-off-by: Supriya Kannery <supriyak@in.ibm.com>
Destroy has a rather negative English connotation. Try to reduce
the impact, so newbies aren't as scared to use it.
* tools/virsh.c: Tweak all destroy documentation.
* tools/virsh.pod: Likewise.
This patch teaches "virsh vcpupin" command to query if no list
is given. Its feature is to show CPU affinity information in more
reader-friendly way.
# virsh vcpupin VM --config
VCPU: CPU Affinity
----------------------------------
0: 1-6,9-20
1: 10
2: 5,9-11,15-20
3: 1,3,5,7,9,11,13,15
When cpulist is omitted, vcpu number is optional. When vcpu number is
provided, information of only specified vcpu is displayed.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
If an application is using libvirt + KVM as a piece of its
internal infrastructure to perform a specific task, it can
be desirable to guarentee the VM dies when the virConnectPtr
disconnects from libvirtd. This ensures the app can't leak
any VMs it was using. Adding VIR_DOMAIN_START_AUTOKILL as
a flag when starting guests enables this to be done.
* include/libvirt/libvirt.h.in: All VIR_DOMAIN_START_AUTOKILL
* src/qemu/qemu_driver.c: Support automatic killing of guests
upon connection close
* tools/virsh.c: Add --autokill flag to 'start' and 'create'
commands
Producing an xml file just for name and description fields is
overkill; this makes life easier from virsh.
* tools/virsh.c (cmdSnapshotCreateAs): New command.
(snapshotCmds): Install it.
* tools/virsh.pod: Document it.
When resetting vcpupin setting, we have to specify all host physical
cpus as a cpulist parameter of virsh vcpupin command. It's a little
tedious.
This patch changes to allow to receive the special keyword 'r' as a cpulist
parameter of virsh vcpupin command when resetting vcpupin setting.
If you set the following:
# virsh vcpupin VM 0 r
the vcpu0 will be pinned to all physical cpus.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
When using vcpupin command, we have to speficy comma-separated list as cpulist,
but this is tedious in case the number of phsycal cpus is large.
This patch improves this by introducing special markup "-" and "^" which are
similar to XML schema of "cpuset" attribute.
The example:
# virsh vcpupin Guest 0 0-15,^8
is identical to
# virsh vcpupin Guest 0 0,1,2,3,4,5,6,7,9,10,11,12,13,14,15
NOTE: The expression is sequentially evaluated, so "0-15,^8" is not identical
to "^8,0-15".
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Define two new virsh commands:
* blockpull: Perform block pull operations (incremental plus start
and stop continuous streams)
* blockpullinfo: Retrieve progress info for continuous block pull
Share print_job_progress() with the migration code.
* tools/virsh.c: implement the new commands
Signed-off-by: Adam Litke <agl@us.ibm.com>
This patch adds the new option (--live, --config and --current) to
"virsh vcpupin" command. The behavior of above aption is the same as
that of "virsh setmem", "virsh setvcpus", and whatnot.
When the --config option is specified, the command affects a persistent
domain, while --live option is specified, it affects a running (live) domain.
The --current option cannot be used with --config or --live at the same
time, and when --current is specified, it affects a "current" domain.
I intentionally set things up so 'virsh help interface' lists
commands in alphabetical order, but 'man virsh' lists them in
topical order; this matches our practice on some other commands.
* tools/virsh.pod: Document all iface commands.
* tools/virsh.c (ifaceCmds): Sort.
The new flags allow to pick current state, config or the live
parameter, with current being the existing API default (0).
This also hooks this to --config, --live, --current parameters for
the memtune virsh command
* include/libvirt/libvirt.h.in: defines the new flags
* tools/virsh.c: adds support at virsh level
* tools/virsh.pod: updates virsh documentation
Based on a smaller patch developed by Moritoshi Oshiro:
https://bugzilla.redhat.com/show_bug.cgi?id=693963
* tools/virsh.pod (freecell): Mention all, and clarify that
optional cellno requires --cellno.
This patch adds the new options (--live, --config, and --current) to
"virsh setmaxmem" command. The behavior of above options is the same
as that of "virsh setmem". When the --config option is specified, a
modification is effective for the persistent domain, while the --live
option is specified, a modification is effective for an active
domain. The --current option is specified, it affects a current
domain.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
This patch adds the new option (--current) to the "virsh setmem" command.
When --current option is specified, it affects a "current" domain.
The word "current" denotes that if a domain is running, it affects
a running domain only; otherwise it affects a persistent domain.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
1) Both "qemuDomainStartWithFlags" and "qemuAutostartDomain" try to
restore the domain from managedsave'ed image if it exists (by
invoking "qemuDomainObjRestore"), but it unlinks the image even
if restoring fails, which causes data loss. (This problem exists
for "virsh managedsave dom; virsh start dom").
The fix for is to unlink the managed state file only if restoring
succeeded.
2) For "virsh save dom; virsh restore dom;", it can cause data
corruption if one reuse the saved state file for restoring. Add
doc to tell user about it.
3) In "qemuDomainObjStart", if "managed_save" is NULL, we shouldn't
fallback to start the domain, skipping it to cleanup as a incidental
fix. Discovered by Eric.
Commit 78ba748ef1 claims to fix
documentation for swap_hard_limit virsh memtune option but it only fixes
documentation in formatdomain.html and libvirt.h. This patch completes
the task by fixing "virsh help memtune" output and memtune section of
virsh man page.
The new commands vol-upload and vol-download, allow a local file
to be transferred to/from a storage volume.
* tools/virsh.c: Add vol-upload and vol-download commands
* tools/virsh.pod: Document new commands
The Open Nebula driver has been unmaintained since it was first
introduced. The only commits have been for tree-wide cleanups.
It also has a major design flaw, in that it only knows about guests
that it has created itself, which makes it of very limited use.
Discussions wrt evolution of the VMWare ESX driver, concluded that
it should limit itself to single-node ESX operation and not try to
manage the multi-node architecture of VirtualCenter. Open Nebula
is a cluster like Virtual Center, not a single node system, so
the same reasoning applies.
The DeltaCloud project includes an Open Nebula driver and is a much
better fit architecturally, since it is explicitly targetting the
distributed multihost cluster scenario.
Thus this patch deletes the libvirt Open Nebula driver with the
recommendation that people use DeltaCloud for managing it instead.
* configure.ac: Remove probe for xmlrpc & --with-one arg
* daemon/Makefile.am, daemon/libvirtd.c, src/Makefile.am: Remove
ONE driver build
* src/opennebula/one_client.c, src/opennebula/one_client.h,
src/opennebula/one_conf.c, src/opennebula/one_conf.h,
src/opennebula/one_driver.c, src/opennebula/one_driver.c: Delete
files
* autobuild.sh, libvirt.spec.in, mingw32-libvirt.spec.in: Remove
build rules for Open Nebula
* docs/drivers.html.in, docs/sitemap.html.in: Remove reference
to OpenNebula
* docs/drvone.html.in: Delete file
This patch adds the new options (--live and --config) to "virsh setmem" command.
The behavior of above options is the same as that of "virsh setvcpus" and so on.
That is, when the --config option is specified, a modification is effective for
the persistent domain. Moreover we can modify the memory size of inactive domains
as well as that of active domains.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Currently users who want to use virDomainQemuMonitorCommand() API or
it's virsh equivalent has to use the same protocol as libvirt uses for
communication to qemu. Since the protocol is QMP with current qemu and
HMP much more usable for humans, one ends up typing something like the
following:
virsh qemu-monitor-command DOM \
'{"execute":"human-monitor-command","arguments":{"command-line":"info kvm"}}'
which is not a very convenient way of debugging qemu.
This patch introduces --hmp option to qemu-monitor-command, which says
that the provided command is in HMP. If libvirt uses QMP to talk with
qemu, the command will automatically be converted into QMP. So the
example above is simplified to just
virsh qemu-monitor-command --hmp DOM "info kvm"
Also the result is converted from
{"return":"kvm support: enabled\r\n"}
to just plain HMP:
kvm support: enabled
If libvirt talks to qemu in HMP, --hmp flag is obviously a noop.
Use it in all places where a memory or storage request size is converted
to a larger granularity. This avoids requesting too small memory or storage
sizes that could result from the truncation done by a simple division.
This extends the round up fix in 6002e0406c
to the whole codebase.
Instead of reporting errors for odd values in the VMX code round them up.
Update the QEMU Argv tests accordingly as the original memory size 219200
isn't a even multiple of 1024 and is rounded up to 215 megabyte now. Change
it to 219100 and 219136. Use two different values intentionally to make
sure that rounding up works.
Update virsh.pod accordingly, as rounding down and rejecting are replaced
by rounding up.
If the memory of guest OS is changed constantly, the live migration
can not be ended ever for ever.
We can use the command 'virsh migrate-setmaxdowntime' to control the
live migration. But the value of maxdowntime is diffcult to calculate
because it depends on the transfer speed of network and constantly
changing memroy size. We need a easy way to control the live migration.
This patch adds the support of forcing guest to suspend at timeout.
With this patch, when we migrate the guest OS, we can specify a
timeout. If the live migration timeouts, auto-suspend the guest OS,
where the migration will complete offline.
The virt-mem program is no longer shipped, but was still being
referenced at the bottom of the virsh and libvirtd man pages.
This patch removes it from those man pages, addressing
BZ# 639603:
https://bugzilla.redhat.com/show_bug.cgi?id=639603
This re-writes the 'virsh console' command so that it uses
the new streams API. This lets it run remotely and/or as a
non-root user. This requires that virsh be linked against
the simple event loop from libvirtd in daemon/event.c
As an added bonus, it can now connect to any console device,
not just the first one.
* tools/Makefile.am: Link to event.c
* tools/console.c, tools/console.h: Rewrite to use the
virDomainOpenConsole() APIs with streams
* tools/virsh.c: Support choosing the console name
via --devname $NAME
* tools/virsh.c (vshParseArgv): Use NULL instead of 0 for pointer,
and symbolic names for has_arg. Give --version an optional arg.
(vshUsage): Document this.
* tools/virsh.pod: Likewise.
To ease debugging this trivial patch allows to find what was compiled
in in the local version of libvirt, this doesn't work for remote access
but that's probably sufficient. With the patch I get on my machine:
paphio:~/libvirt/tools -> ./virsh -V
Virsh command line tool of libvirt 0.8.4
See web site at http://libvirt.org/
Compiled with support for:
Hypervisors: Xen QEmu/KVM UML OpenVZ LXC ESX PHYP Test
Networking: Remote Daemon Network Bridging Netcf Nwfilter
Storage: Dir Disk Filesystem SCSI Multipath iSCSI LVM
Miscellaneous: SELinux Secrets Debug Readline
paphio:~/libvirt/tools ->
* tools/virsh.c: add -V option
* tools/virsh.pod: document the extension
Now that the virsh parsing has been revamped, we can
implement qemu-monitor-command. This is basically the same
as it was in previous iterations, but has now been tested to
work both with the plain text monitor and the QMP monitor.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
* tools/virsh.c: add missing option from the CLI to allows setting
up the NIC model type when attaching an interface
* tools/virsh.pod: extend documentation
* AUTHORS: add Osier Yang to the list
* tools/virsh.c (cmdSetvcpus): Add new flags. Let invalid
commands through to driver, to ease testing of hypervisor argument
validation.
(cmdMaxvcpus, cmdVcpucount): New commands.
(commands): Add new commands.
* tools/virsh.pod (setvcpus, vcpucount, maxvcpus): Document new
behavior.
* docs/formatdomain.html.in: Add memtune element details, added min_guarantee
* src/libvirt.c: Update virDomainGetMemoryParameters api description, make
it more clear that the user first needs to call the api to get the number
of parameters supported and then call again to get the values.
* tools/virsh.pod: Add usage of new command memtune in virsh manpage
Old virsh command parsing mashes all the args back into a string and
miss the quotes, this patches fix it. It is also needed for introducing
qemu-monitor-command which is very useful.
This patches uses the new vshCommandParser abstraction and adds
vshCommandArgvParse() for arguments vector, so we don't need
to mash arguments vector into a command sting.
And the usage was changed:
old:
virsh [options] [commands]
new:
virsh [options]... [<command_string>]
virsh [options]... <command> [args...]
So we still support commands like:
"define D.xml; dumpxml D" was parsed as a commands-string.
and support commands like:
we will not mash them into a string, we use new argv parser for it.
But we don't support the command like:
"define D.xml; dumpxml" was parsed as a command-name, but we have no such command-name.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
This patch removes the individual author names from the libvirtd and virsh
man pages, instead referring to the main AUTHORS file distributed with
libvirt. This approach is needed, as we can't guarantee unicode support
across all versions of pod2man used with libvirt.
Additionally, this patch includes the libvirtd man page in the spec file
used with "make rpm". Without this patch "make rpm" is broken.
This patch adds a new --details option to the virsh vol-list
command, making its output more useful when many luns are
present.
Addresses BZ # 605543
https://bugzilla.redhat.com/show_bug.cgi?id=605543
This patch adds a new --details option to the virsh pool-list
command, making its output more useful to people who use virsh
for significant lengths of time.
Addresses BZ # 605543
https://bugzilla.redhat.com/show_bug.cgi?id=605543
http://bugzilla.redhat.com/601143, part 1 - document existing
behavior. Ever since Mar 2010 (commit ced154cb), the use of
'attach-disk' or 'attach-device' to change cdrom/floppy media has been
documented but deprecated, but the replacement to use 'update-device'
was not documented.
* tools/virsh.c (cmdAttachInterface, cmdAttachDisk): Fix bad error
message.
* tools/virsh.pod (attach-device, attach-disk): Refer to
update-device for cdrom and floppy behavior.
(update-device): Add documentation.
Presently the vol-key command only supports being provided with
a volume path.
This patch adds support for providing it with a pool and volume
identifier pair as well.
virsh # vol-key --pool <pool-name-or-uuid> <vol-name-or-path>
Make 'start --paused' mirror 'create --paused'.
* tools/virsh.c (cmdStart): Use new virDomainCreateWithFlags API
when needed.
* tools/virsh.pod (start): Document --paused.
This patch adds two new parameters to the vol-create-as command:
--backing-vol <volume-name-or-key-or-path>
--backing-vol-format <format-of-backing-vol>
virsh # vol-create-as guest_images_lvm snapvol1 5G --backing-vol \
rhel6vm1lun1
Vol snapvol1 created
virsh # vol-create-as image_dir qcow2snap2 5G --format qcow2 \
--backing-vol imagevol1.qcow2 \
--backing-vol-format qcow2
Vol qcow2snap2 created
Additionally, the virsh man page update fixes incorrect snapshot
parameters that were included in my prior bulk volume command patch.
This is just a trivial patch to virsh.pod (from git master). It adds the
following pieces to the virsh man page:
+ Shows the --inactive and --all optional parameters for the list
command.
Closes Bugzilla #575512, reported by Renich Bon Ciric
https://bugzilla.redhat.com/show_bug.cgi?id=575512
+ Corrects the existing description of the list command, to now say
that only running domains are listed if no domains are specified.
The man page up until this point has said all domains are listed if
no domains are specified, which is incorrect.
+ Adds the "shut off" state to the list of states for the list
command.
+ Adds a missing =back around line 755, that pod2man was complaining
was missing.
With Eric Blake's spelling corrections applied.
Unfortunately after the 0.8.0 release, but here's a beginning of the
documentation of the nwfilter functionality.
Document several missing commands. There's more work that could be
done, but incremental improvements is better than no patch at all.
* tools/virsh.pod (autostart, connect): Improve grammar.
(create): Improve example.
(domjobabort, domjobinfo, domxml-from-native, domxml-to-native):
Document.
(storage pool commands): New section.
Call me lazy: some shells use exit (e.g. sh), others use quit (e.g. ftp),
but I never remember which. So it's faster to write a patch to make
virsh take both than it is to take a 50-50 guess, and get it wrong
in half of my attempts.
* tools/virsh.c (commands): Add 'exit'.
* tools/virsh.pod: Document it.
Common Unix practice is to prefer VISUAL over EDITOR, particularly if
the editor of choice spawns a new window. Thus, it is also common to
see settings like EDITOR='emacs -nw', with the expectation that the
shell will parse this as an argument to 'emacs' and not try to invoke
a file containing a space.
If a user puts junk in EDITOR, they deserve what they get (much more
than virsh will misbehave); furthermore, sudo scrubs EDITOR by
default. So the blind use of metacharacters in EDITOR should not be
considered too much of a security issue.
* tools/virsh.c (editFile): Prefer VISUAL over EDITOR. Don't
reject shell metacharacters in EDITOR.
* tools/virsh.pod (edit, net-edit, ENVIRONMENT): Document VISUAL.
Fixes https://bugzilla.redhat.com/show_bug.cgi?id=487738.