- Devel - libvirt List Archives

Re: [Libvir] Request for additional entry points
by Bret McMillan 27 Apr '06

27 Apr '06

On Thu, 2006-04-13 at 12:00 -0400, libvir-list-request(a)redhat.com wrote: > We've discussed this before and I think the most compelling argument for > passive domain support in libvirt (and even at a lower level such as > Xend) is the following scenario: > > Let's say a user creates a virtual FC6 virtual machine that she is going > to use to test her apps under Gnome (she's a KDE user). The machine > isn't always there b/c she rarely needs it. She created it with some > nifty KDE tool that has yet to be written. > > Of course, she finds out about this neat applet that you can use to > managing running domains. If there isn't a common way of accessing > passive domains then she won't see the FC6 VM. > > Now, I don't think that *all* domains should have to have passive > equivalents (which is a requirement in the CIM provider today) because > of some of the scenarios you outlined. However, I think not attempting > to have a common API for passive domains is going to creative a mess as > we get a larger number of management tools. I think we're confusing the notion of what a passive domain is with what config files happen to be sitting on / exposed to the dom0 machine. I could very easily look at having an rdbms store the info about the passive domain, hand that down to the dom0 via rpc, and directly call the createLinux call. To me, that's still a passive domain, even though it's configs haven't touched disk yet. I guess I'm also struggling to understand why you'd toss this into xenstore... it just seems this is a higher level concept that needs to be tracked in too specific a way by management systems. --Bret

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[Libvir] Perl API for using libvirt
by Daniel P. Berrange 26 Apr '06

26 Apr '06

Hi Folks, I had a couple of hours spare, so I put together a set of Perl bindings for libvirt. I'm currently calling the module Sys::Virt which seems to be the most appropriate location in the CPAN namespace, but I'm open to suggestions if people think that sucks. I've currently got near 100% coverage of the C APIs, but not exposed all the static constants yet. There are a couple of trivial example programs illustrating use of the API for extracting info about domains.=20 For now you can grab a snapshot of the source for the binding using=20 Mercurial from the URL: http://hg.berrange.com/libraries/sys-virt When I've tested it more completely I'll upload it to CPAN Regards, Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

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RE: [Libvir] Problems installing libvir
by Subrahmanian, Raj 25 Apr '06

25 Apr '06

Daniel, This was more of a hurried hack just changing all curses to ncurses :-) I know it's no excuse, but I was in a hurry to start linking to libvirt. I will work on a cleaner change to configure.in and forward it to you later today? Thanks Raj PS. Didn't Jim Fehlig mention that he has already fixed this? -----Original Message----- From: Daniel Veillard [mailto:veillard@redhat.com] Sent: Tuesday, April 25, 2006 4:06 AM To: Subrahmanian, Raj Cc: libvir-list(a)redhat.com Subject: Re: [Libvir] Problems installing libvir On Mon, Apr 24, 2006 at 09:25:45PM -0400, Subrahmanian, Raj wrote: > > ncurses vs. curses ? > Ohh, and I was looking right at it! > Sorry folks. > I hacked the configure file to look for ncurses and sure enough it > worked. Can you send the diff you made to configure.in so we can fix configure to work with both libraries ? Daniel -- Daniel Veillard | Red Hat http://redhat.com/ veillard(a)redhat.com | libxml GNOME XML XSLT toolkit http://xmlsoft.org/ http://veillard.com/ | Rpmfind RPM search engine http://rpmfind.net/

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RE: [Libvir] Problems installing libvir
by Subrahmanian, Raj 25 Apr '06

25 Apr '06

> ncurses vs. curses ? Ohh, and I was looking right at it! Sorry folks. I hacked the configure file to look for ncurses and sure enough it worked. Thanks for the help. Raj

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[Libvir] Re: [Xen-cim] LTC provider working on SLES/openwbem
by Jim Fehlig 25 Apr '06

25 Apr '06

Daniel Veillard wrote: >On Thu, Apr 20, 2006 at 04:24:28PM -0600, Jim Fehlig wrote: > > >>FYI, >> >>I have managed to get one of the LTC providers (Xen_ComputerSystem) >>working on SLES using openwbem cimom, the xm shim, and libvirt. The >>following changes were made: >> >>libvirt >>- changed xend_parse_sexp_desc() to not fail if kernel not found. sexp >>from xend does not contain kernel for domain 0. >> >> > > Makes sense, could you send that patch ? > > thanks, > >Daniel > > Attached. Jim

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[Libvir] Problems installing libvir
by Subrahmanian, Raj 25 Apr '06

25 Apr '06

All, I am trying to install libvir on my SUSE box. The .configure command halts with the following message. ibxml2 xml2-config ... yes ('') checking for initscr in -lcurses... no configure: error: curses library not found But, I have installed curses, and cdk. linux:~/xen/libvirt-0.1.0 # whereis curses curses: /usr/include/curses.h /usr/include/curses What am I missing out here? thanks Raj

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[Libvir] FC5 bug with kernel/initrd paths
by Daniel Hiltgen 21 Apr '06

21 Apr '06

I just started experimenting with libvirt on FC5 and ran into something that doesn't seem quite right. I've created a VM using the xenguest-install.py script. I've tried grabbing the XML from virsh using dumpxml, but the kernel and initrd paths are invalid. Specifically: ... <os> <type>linux</type> <kernel>/var/lib/xen/vmlinuz.276riA</kernel> <initrd>/var/lib/xen/initrd.z1bslj</initrd> <cmdline>ro root=/dev/VolGroup00/LogVol00 rhgb quiet</cmdline> </os> ... (I see the same bogus paths in xm list --long) If I shut down the VM and attempt to power it back on using the API and this XML definition, it fails with: libvir: Xen Daemon error : POST operation failed: No such domain guest1i Failed to get devices for domain guest1 error: Failed to create domain If I boot up the VM, and copy the kernel and initrd image out of it's /boot partition onto the main filesystem, and tweak the XML to point to those paths, I can boot the system through libvirt, but the files are automatically deleted after I boot. Also, every time I boot using xm create, I get a different bogus kernel/initrd path. Is this expected behavior, or is there a bug/mismatch between libvirt and the underlying Xen modules in FC5? Thanks, Daniel

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[Libvir] Add a timestamp to virDomainInfo ?
by Daniel P. Berrange 19 Apr '06

19 Apr '06

The primary use of the virDomainInfo data is in calculating resource utilization over time. The CPU runtime data, however, is represented as a counter, so to calulate utilization requires some transformations. Basically subtract the CPU runtime value for time X, from the value at time Y, and divide the result by Y-X. Obviously this requires us to know the times X & Y. Currently the virDomainInfo structure does not contain this information though, so apps have to call something like gettimeofday() before virDomainGetInfo(), to record the timestamp of each virDomainInfo record. The problem is that this is a pretty poor approximation - particularly if libvirt is talking via XenD, a non-trivial period of time can pass between the call to gettimeofday() and the values for virDomainInfo actually sampled. Thus I would like to suggest that the virtDomainInfo structure be expanded to add an extra data field of type 'struct timeval' to record a high resolution timestamp. Now currently this wouldn't help accuracy all that much, since libvirt would still be filling this in much the same way as the app did. It does however, open the door to having Xen itself provide an accurate timestamp back to libvirt, which would in turn benefit apps without requiring further code change. Regards, Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

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[Libvir] libvirt.org is down
by Daniel Veillard 18 Apr '06

18 Apr '06

I will try to get it restarted tomorrow morning, sorry for the annoyance. Daniel -- Daniel Veillard | Red Hat http://redhat.com/ veillard(a)redhat.com | libxml GNOME XML XSLT toolkit http://xmlsoft.org/ http://veillard.com/ | Rpmfind RPM search engine http://rpmfind.net/

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[Libvir] Request for additional entry points
by Jim Fehlig 13 Apr '06

13 Apr '06

As discussed on the xen-cim call on 3/31, the Xen CIM provider needs some additional entry points in libvirt. I would like to open a discussion about adding the following entry points to libvirt. virDomainSetConfig(virConnectPtr conn, const char *xmlDesc) Stores the domU config data in xenstore. The domU is not running yet but enumerating domains would return the config for the domain as well as any running domains. This would support the notion of a defined but inactive virtual machine. Daniel noted that the config could be cached in libvirt, preventing (to some degree) modifying the config out-of-band prior to activating the domain. Note that the current virConnectListDomains() implies enumerating only running domains since a list of domain IDs is returned. Perhaps virConnectListDomains() will have to be expanded to include defined domains or another entry point to enumerate defined domains. Related would be activating a defined domain. Would clients get the domain config (via virDomainGetXMLDesc()) and subsequently pass it to virDomainCreateLinux() or another entry point to create a defined domain? virDomainDeleteConfig(virConnectPtr conn, const char *name) Removed domU config from xenstore (or cache). DomU no longer "exists". What if domain is active upon invocation? virDomainSetCurrentMemory(virDomainPtr domain, unsigned long memory) Adjust the current memory usage for a domain. virDomainReboot(virDomainPtr domain) Reboot the domain. virDomainMigrate(virDomainPtr domain, const char *host) ?? Not sure what can of worms might be opened by this one :-). Thoughts? BTW, I can certainly help with the effort if an agreement is reached on adding this functionality. Regards, Jim

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