March 2010 - Devel - libvirt List Archives

[libvirt] [RFC]: Snapshot API
by Chris Lalancette 24 Mar '10

24 Mar '10

Hello, As some of you know, I've been working on a new snapshot API. This API is heavily based on DanB's earlier API proposed here: https://www.redhat.com/archives/libvir-list/2010-January/msg00626.html I've made some modifications to make it more libvirt-ish, and to add a couple of features I think it lacked. The full documentation is below. Any comments are appreciated. /* NOTE: struct _virDomainSnapshot is a private structure, ala * struct _virDomain. */ typedef struct _virDomainSnapshot virDomainSnapshot; /* Take a snapshot of the current VM state */ virDomainSnapshotPtr virDomainSnapshotCreateXML(virDomainPtr domain, const char *xmlDesc, unsigned int flags); /* Dump the XML of a snapshot */ /* NOTE: see below for proposed XML */ char *virDomainSnapshotGetXMLDesc(virDomainSnapshotPtr snapshot, unsigned int flags); /* Return the number of snapshots for this domain */ int virDomainSnapshotNum(virDomainPtr domain, unsigned int flags); /* Get the names of all snapshots for this domain */ int virDomainListSnapshotNames(virDomainPtr domain, char **names, int nameslen, unsigned int flags); /* Get a handle to a named snapshot */ virDomainSnapshotPtr virDomainSnapshotLookupByName(virDomainPtr domain, const char *name, unsigned int flags); /* Set this snapshot as the current one for a domain, to be * used next time domain is started */ int virDomainSnapshotActivate(virDomainSnapshotPtr snapshot, unsigned int flags); /* Deactivate a snapshot - with no flags, the snapshot is not used anymore, * but also not removed. With a MERGE flag, it merges the snapshot into * the base image. With a DISCARD flag, it deletes the snapshot. MERGE * and DISCARD are mutually-exclusive. Note that this operation can * generally only happen when the domain is shut down, though this is * hypervisor-specific */ typedef enum { VIR_DOMAIN_SNAPSHOT_DEACTIVATE_MERGE, VIR_DOMAIN_SNAPSHOT_DEACTIVATE_DISCARD, } virDomainSnapshotDeactivate; int virDomainSnapshotDeactivate(virDomainSnapshotPtr snapshot, unsigned int flags); int virDomainSnapshotFree(virDomainSnapshotPtr snapshot); NOTE: During snapshot creation, *none* of the fields are required. That is, you can call virDomainSnapshotCreateXML() with an XML of "<domainsnapshot/>". In this case, the individual driver will make up a <name> for you, the <creationdate> will be set to the current time+date, <description> will be empty, <state> will be "off", <compression> will be empty, and <parent> will be empty. If you do want to specify some fields during virDomainSnapshotCreateXML(), note that the only ones that are settable are <name>, <description>, <compression>, and <parent>; the rest are ignored, and filled in by the driver when the snapshot is actually created. NOTE: <parent> is used to create "trees" of snapshots, and may or may not be supported by individual hypervisor implementations. If <parent> is specified and the underlying hypervisor does not support it, an error will be thrown. NOTE: <compression> is used to compress snapshots, and may or may not be supported by individual hypervisor implementations. If <compression> is specified and the underlying hypervisor does not support it, an error will be thrown. <domainsnapshot> <name>XYZ</name> <creationdate>...</creationdate> <description> ....blah.... </description> <state>RUNNING</state> <domain> <uuid>XXXXX-XXXX-XXXX-XXXX-XXXXXXXXX</uuid> </domain> <compression>gzip</compression> <parent> <name>ABC</name> </parent> </domainsnapshot> The virsh commands will be: virsh snapshot-create [--compress] <dom> <xmlfile> virsh snapshot-list <dom> virsh snapshot-dumpxml <dom> <name> virsh snapshot-activate <dom> <snapshotname> virsh snapshot-deactivate <dom> <snapshotname> [--merge|--delete] -- Chris Lalancette

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[libvirt] Unable to open virt-manager
by Doron Fediuck 24 Mar '10

24 Mar '10

Hi, I'm trying to work remotely on a server with F12, using vnc. When I start virt-manager, I do not get the authentication popup, and instead I get this message: Unable to open connection to hypervisor URI 'qemu:///system': authentication failed Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/connection.py", line 872, in _try_open None], flags) File "/usr/lib64/python2.6/site-packages/libvirt.py", line 102, in openAuth if ret is None:raise libvirtError('virConnectOpenAuth() failed') libvirtError: authentication failed RPM versions: libvirt-0.7.1-15.fc12.x86_64 libvirt-client-0.7.1-15.fc12.x86_64 python-virtinst-0.500.1-2.fc12.noarch virt-viewer-0.2.0-1.fc12.x86_64 virt-manager-0.8.2-1.fc12.noarch virt-ctrl-1.0.1-4.fc12.x86_64 libvirt-python-0.7.1-15.fc12.x86_64 Any idea what causes the popup to fail ?

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Re: [libvirt] [Qemu-devel] Re: Supporting hypervisor specific APIs in libvirt
by Avi Kivity 24 Mar '10

24 Mar '10

On 03/24/2010 02:30 PM, Paul Brook wrote: >> On 03/23/2010 09:24 PM, Anthony Liguori wrote: >> >>> We also provide an API for guest creation (the qemu command line). >>> >> As an aside, I'd like to see all command line options have qmp >> equivalents (most of them can be implemented with a 'set' command that >> writes qdev values). This allows a uniform way to control a guest, >> whether at startup or runtime. You start with a case, cold-plug a >> motherboard, cpus, memory, disk controllers, and power it on. >> > The main blocker to this is converting all the devices to qdev. "partial" > conversions are not sufficient. It's approximately the same problem as a > machine config file. If you have one then the other should be fairly trivial. > Agreed. > IMO the no_user flag is a bug, and should not exist. > Sorry, what's that? -- error compiling committee.c: too many arguments to function

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[libvirt] prematurely pushed my build/portability/clean-up patches
by Jim Meyering 24 Mar '10

24 Mar '10

Jim Meyering wrote: > Eric Blake wrote: >> On 03/23/2010 09:07 AM, Philipp Hahn wrote: >>> The conversion from seconds to milliseconds should only be done for >>> actual delays >= 0, not for the magic -1 value used for infinite >>> timeouts. >> >> ACK. > > Thanks. I pushed that. Whoops. While pushing that, I mistakenly also pushed my four unreviewed build/portability/clean-up patches. Sorry about that.

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[libvirt] [PATCH] poll(-0.001) does not sleep forever.
by Philipp Hahn 24 Mar '10

24 Mar '10

The conversion from seconds to milliseconds should only be done for actual delays >= 0, not for the magic -1 value used for infinite timeouts. Signed-off-by: Philipp Hahn <hahn(a)univention.de> --- examples/domain-events/events-python/event-test.py | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-)

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[libvirt] [PATCH] tests: Don't add extra padding if counter mod 40 is 0
by Matthias Bolte 23 Mar '10

23 Mar '10

--- tests/test-lib.sh | 10 ++++++---- tests/testutils.c | 2 +- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/tests/test-lib.sh b/tests/test-lib.sh index 43265f3..57fd438 100644 --- a/tests/test-lib.sh +++ b/tests/test-lib.sh @@ -55,10 +55,12 @@ test_final() if test "$verbose" = "0" ; then mod=`eval "expr $ $counter + 1 $ % 40"` - for i in `seq $mod 40` - do - echo -n " " - done + if test "$mod" != "0" -a "$mod" != "1" ; then + for i in `seq $mod 40` + do + echo -n " " + done + fi if test "$status" = "0" ; then printf " %-3d OK\n" $counter else diff --git a/tests/testutils.c b/tests/testutils.c index 8764673..99bd9df 100644 --- a/tests/testutils.c +++ b/tests/testutils.c @@ -531,7 +531,7 @@ cleanup: virResetLastError(); if (!virTestGetVerbose()) { int i; - for (i = (testCounter % 40) ; i < 40 ; i++) + for (i = (testCounter % 40) ; i > 0 && i < 40 ; i++) fprintf(stderr, " "); fprintf(stderr, " %-3d %s\n", testCounter, ret == 0 ? "OK" : "FAIL"); } -- 1.6.3.3

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[libvirt] [PATCH] Don't mix relative and absolute paths.
by Philipp Hahn 23 Mar '10

23 Mar '10

autoconf goes to great lengths to calculate a proper MKINSTALLDIRS path, so just export the variable for gettext, but don't overwrite it with a broken path: $(top_builddir) is a relative path, while $ac_aux_dir can be an absolute path. Signed-off-by: Philipp Hahn <hahn(a)univention.de> --- configure.ac | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)

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[libvirt] [PATCH 0/3] Refactor XML parsing code
by Jiri Denemark 23 Mar '10

23 Mar '10

Almost identical XML parsing code for either strings or files was copied 15 times. Since it was needed on two other places for parsing CPU XML strings with correct error reporting, I decided to factor the parsing code out to xml.c and used this one implementation in all other places. Jiri Denemark (3): Introduce XML parsing utility functions Use common XML parsing functions Fix error reporting when parsing CPU XML strings src/conf/domain_conf.c | 130 ++++++--------------------------------- src/conf/interface_conf.c | 93 ++++------------------------ src/conf/network_conf.c | 93 ++++------------------------ src/conf/node_device_conf.c | 60 +----------------- src/conf/secret_conf.c | 56 ++--------------- src/conf/storage_conf.c | 110 +++------------------------------- src/cpu/cpu.c | 11 ++- src/util/xml.c | 142 ++++++++++++++++++++++++++++++++++++++++++- src/util/xml.h | 19 ++++++ 9 files changed, 231 insertions(+), 483 deletions(-)

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[libvirt] [RFC] events scripts support
by Daniel Veillard 23 Mar '10

23 Mar '10

We would like to introduce a way to configure system wide a script which would be called when some event happens. The script is a single executable set as a libvirtd option by the system administrator (assuming one runs the system libvirtd) or the user (assuming a user run libvirtd). The script could be invoked on daemon events, for example starting stopping, or reloading (SIGHUP), on domain events for example before a domain starts, or after its stops, and possibly on other kind of events detected by the daemon (storage or interface ...) My current thinking is to add the following two variables to libvirtd.conf: # Event scripts # An optional path to a script handling various kind of events like # domain start, domain end, pre and post migration, etc... # The events_script must be a path to the script or binary handling # the # events. # The events_set is a list of space separated name for the event type # the script should receive # # events_script="/etc/libvirt/events" # events_set="daemon domain" The script aruguments would be - the object kind: e.g. "domain" - the object name: e.g. the domain name - the event itself: e.g. "start" - sub event qualifier: e.g. "before" - an optional extra information for example in case of migration the destination or source So for example if the two variables as set as sugegsted, /etc/libvirt/events domain foo start before would be run by the daemon before the lunch of a domain which could have been initiated by the user when running "virsh foo start". The script exec return value is expected to be 0 unless indicating an error, in that case the libvirtd command would fail, for example if the command launched for "virsh foo start" failed with an error value the domain won't be started. This is a new kind of API in libvirt(d) so I'm submitting this for review. There could be some challenging issues, for example naming i.e. is the object "external" name like 'foo' the right thing to pass or should we also provide the uuid, making sure the arguments for the scripts and the behaviour is generic enough, and also how to handle potential recursion and avoid deadlock if the events script happen to use libvirt. I hope to have some initial patches by tomorrow, but I'm probably forgetting things, so feedback welcome ! Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel(a)veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/

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Re: [libvirt] FW: [PATCH 1/4] Addition of XenAPI support to libvirt
by Daniel Veillard 23 Mar '10

23 Mar '10

On Fri, Feb 19, 2010 at 11:33:36AM +0000, Sharadha Prabhakar (3P) wrote: > > thanks for the patch, just started to look at it. > > I assume that by libxenserver you mean the code to be added under src > in a following patch, right ? > > -> libxenserver is a library which provides APIs for performing various > Operations on the hypervisor. You can download it from > http://community.citrix.com/download/attachments/38633496/libxenserver-5.5.… > libxenserver folder should be in the same directory level of libvirt. Sorry that's not possible. Either the code is in libvirt, and in that case it doesn't have to be downloaded, but part of the patch submission (and managed on this list) , or it's a new external dependancy and it's availability must be checked by configure.ac. If we add a new dependancy, it must also be checked for Licence compatibility. So far we have always refused to use a third party library to access the hypervisor itself, libvirt(d) talking directly to the hypervisor components or launching it directly. For example we don't rely on the VMWare libraries to talk to ESX. > [...] > > +endif > > +#libvirt_driver_xenapi_la_LIBADD = $(XENAPI_LIBS) > > +libvirt_driver_xenapi_la_CFLAGS = $(XEN_CFLAGS) \ > > + $(shell xml2-config --cflags) \ > > + $(shell curl-config --cflags) > > +libvirt_driver_xenapi_la_LDFLAGS = -L@top_srcdir@/../libxenserver/ -lxenserver -g $(shell xml2-config --libs) \ > > + $(shell curl-config --libs) > > Hum, libxml2 is already fully detected in configure.ac, use the > LIBXML_* variables instead of trying to exec xml2-config. > > -> I've added the LIBXML_ flags in Makefile.am and posted the patch. okay, we will review this, but note that we start the feature freeze for 0.7.7 this week-end, so next week is more likely to be focused on bug fixes for already commited features. > Similary libcurl i looked at in configure.ac for ESX, this need > to be modified to be checked more generally and the LIBCURL_* > variables need to be used here too. > > -> I didn't quite understand the libcurl part you mentioned. I too noticed that ESX has > a piece of code in configure.ac to set the libcurl flags, do you want me to do add a similar > bit of code in configure.ac for XenAPI that defines LIBCURL flags and then add in my Makefile.am? the code to look for libcurl in configure.ac is currently only activated if esx support is on. It must be run if either esx or xen-api are selected, the ESX portion need to be modified accordingly, and your parts and Makefiles patches too. Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel(a)veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/

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