- Devel - libvirt List Archives

[libvirt] new API to get list of *all* interfaces matching a MAC
by Laine Stump 25 Aug '09

25 Aug '09

(This probably seems like overanalysis of a simple problem. That's what I'm best at ;-) Due to oversight, the function virInterfaceLookupByMACString() can only return a single interface, but it's possible that a host may have more than one interface with the same MAC. Since the API had already been released by the time we realized this, the existing function will remain and a new one added that can return a list of interfaces. This new API will need to deal with the fact that the list length is effectively unbounded. I can see three ways of dealing with this, and want to learn which is preferred by others before spending time on the implementation. 1) The array containing the list is allocated by libvirt, freed by caller. int virInterfaceLookupAllByMACString(virConnectPtr conn, const char *mac, virInterfacePtr **matches); "matches" will point to an array of virInterfacePtr, and that array's length will be the return value. This array will be allocated by libvirt, but must be freed by the application when it's finished. Usage (ignoring errors, of course :-): virInterfacePtr *matches; int matchCt; matchCt = virInterfaceLookupAllByMACString(conn, "00:01:02:03:04:05", &matches); for (i = 0; i < matchCt; i++) { /* do something with an interface */ virInterfaceFree(matches[i]); } free(matches); 2) The array containing the list is allocated by the application, and its length sent to libvirt. Libvirt then returns the actual number of matches, which may be greater than the max length sent by the application, but only copies as many as the application asked for. If the application sends 0 as maxMatches and/or a NULL pointer instead of a pointer to an array, libvirt will return the actual length, but not the list itself. For example, if there are 3 interfaces matching, and maxMatches is set to 2, the function will still return 3, but only set two items in the matches array. int virInterfaceLookupAllByMACString(virConnectPtr conn, const char *mac, virInterfacePtr **matches, int maxMatches); This puts all the functionality needed in a single API function, but it will generally need to be called twice - once to learn the length, and the second (after allocating an array of appropriate size) to retrieve the list. virInterfacePtr *matches; int matchCtA, matchCtB; matchCtA = virInterfaceLookupAllByMACString(conn, "00:01:02:03:04:05", NULL, 0); matches = malloc (matchCt * sizeof(virInterfacePtr)); matchCtB = virInterfaceLookupAllByMACString(conn, "00:01:02:03:04:05", &matches, matchCt); for (i = 0; i < min(matchCtA, matchCtB); i++) { /* do something with an interface */ virInterfaceFree(matches[i]); } free(matches); 3) Again, the array containing the list is allocated by the application, but it learns the proper length to allocate by calling a different API function. The lookup function itself returns the number of interfaces delivered in the array, rather than the number of matches it *wanted* to put in the array. int virInterfaceCountAllByMACString(virConnectPtr conn, const char *mac); int virInterfaceLookupAllByMACString(virConnectPtr conn, const char *mac, virInterfacePtr **matches, int maxMatches); Usage: virInterfacePtr *matches; int matchCt; matchCt = virInterfaceCountAllByMACString(conn, "00:01:02:03:04:05"); matches = malloc (matchCt * sizeof(virInterfacePtr)); matchCt = virInterfaceLookupAllByMACString(conn, "00:01:02:03:04:05", &matches, matchCt); for (i = 0; i < matchCt; i++) { /* do something with an interface */ virInterfaceFree(matches[i]); } free(matches); ******* (3) is closest to behavior of other libvirt APIs, but requires more functions in the API, and could lead to situations where newly added interfaces aren't in the list (if a new interface is added between calling the Count function and the Lookup function) . (2) has a more compact API (one which matches the netcf API exactly), but has the same problems with potential bad counts. (1) seems like the cleanest API, but I don't know what others' opinions are on having libvirt allocate the array (since that's not how its done for other similar things, eg virConnectListInterface, virConnectListNetworks, etc), or maybe there's some limitation of the RPC I haven't considered that makes it unfeasible. Which should I implement?

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[libvirt] error: failed to connect to hypervisor (openvz)
by AL.Gabteni 25 Aug '09

25 Aug '09

Hi im trying to use libvirt with openvz since 2 days but without luck ,i allways get error: failed to connect to hypervisor (openvz) ; the test connection is working , any help will be appreciated . Regards

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[libvirt] Small patch for ruby-libvirt to add api wrapping for DomainAttachDevice and DomainDetachDevice
by Jacob Leaver 25 Aug '09

25 Aug '09

--- ext/libvirt/_libvirt.c.orig 2009-01-19 18:24:22.000000000 -0800 +++ ext/libvirt/_libvirt.c 2009-01-19 18:24:39.000000000 -0800 @@ -728,6 +728,21 @@ gen_call_void(virDomainSave, conn(s), domain_get(s), StringValueCStr(to)); } +/* + * Call +virDomainAttachDevice+[http://www.libvirt.org/html/libvirt-libvirt.html#virDomainAttachDevice] + */ +VALUE libvirt_dom_attach_device_xml(VALUE s, VALUE xml) { + virDomainPtr dom = domain_get(s); + return virDomainAttachDevice(dom, StringValueCStr(xml)); +} + +/* + * Call +virDomainDetachDevice+[http://www.libvirt.org/html/libvirt-libvirt.html#virDomainDetachDevice] + */ +VALUE libvirt_dom_detach_device_xml(VALUE s, VALUE xml) { + virDomainPtr dom = domain_get(s); + return virDomainDetachDevice(dom, StringValueCStr(xml)); +} /* * Call +virDomainCoreDump+[http://www.libvirt.org/html/libvirt-libvirt.html#virDomainCoreDump] @@ -1921,7 +1936,8 @@ rb_define_method(c_domain, "autostart", libvirt_dom_autostart, 0); rb_define_method(c_domain, "autostart=", libvirt_dom_autostart_set, 1); rb_define_method(c_domain, "free", libvirt_dom_free, 0); - + rb_define_method(c_domain, "attach_device", libvirt_dom_attach_device_xml, 1); + rb_define_method(c_domain, "detach_device", libvirt_dom_detach_device_xml, 1); /* * Class Libvirt::Domain::Info */

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[libvirt] OS Eject & Removable Media
by Jacob Leaver 25 Aug '09

25 Aug '09

Greetings all, First, I'd like to thank everyone that's working on the libvirt project, it's certainly making my life a better place. Second, (there's always a second, eh?) I am using libvirtd 0.6.4 and KVM qemu-kvm-0.10.5, and when a guest OS ejects media, libvirtd doesn't seem to pick up the change. Looking through the API, I don't see a provision to probe for a list of block devices, so although qemu and kvm know about media changes, I don't think there's a way for libvirtd to know about them. I've scanned the list archives, and haven't really seen any discussion of this, but I'd be more than happy to be directed somewhere. Also, I have a couple of minor and hackish patches for the ruby bindings for attaching and removing devices, if someone's interested. Sincerely, Jacob Leaver

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[libvirt] network not autostarting
by Mariano Absatz 24 Aug '09

24 Aug '09

Hi, I'm using libvirt-bin 0.6.1 from the standard ubuntu repositories under ubuntu 9.04 (jaunty). I have, beside the default network, another one called "isolated" using the following description file: <network> <name>isolated</name> <uuid>51cffbcc-88f5-4edc-a81c-1765c1045691</uuid> <bridge name='virbr%d' stp='on' forwardDelay='0' /> <ip address='10.3.14.1' netmask='255.255.255.0'> <dhcp> <range start='10.3.14.128' end='10.3.14.254' /> </dhcp> </ip> </network> I have configured it with "net-autostart" and the symlink in the /etc/libvirt/qemu/networks/autostart/ autostart directory is just fine... however, it isn't starting automatically anymore (and it used to start up before)... Any hints on what to look up and where? TIA. -- Mariano Absatz - "El Baby" el.baby(a)gmail.com www.clueless.com.ar -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- _ | / \ | \ / ASCII RIBBON CAMPAIGN | X AGAINST HTML MAIL | / \ www.asciiribbon.org | | | -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- * TagZilla 0.066 * http://tagzilla.mozdev.org

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[libvirt] Communicating with libvirt from windows
by anuj rampal 24 Aug '09

24 Aug '09

Hi, I have KVM running on one of my machine and I can controle the geues OS using the virt-manager and Virsh tools. Now what I want to do is talk to libvirt from my windows machine. I tried to compile libvirt for windows but couldnt get any success with that. Is there a way by which i can talk to libvirt without this client..?? As in can i talk to libvirt over TCP sockets using xml (something like that)...?? Thanks a lot in advance. Regards Anuj

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[libvirt] [PATCH] Ignores EOPNOTSUPP when attempting to access an image on an NFS share.
by Darryl L. Pierce 21 Aug '09

21 Aug '09

rhbz#517157 Signed-off-by: Darryl L. Pierce <dpierce(a)redhat.com> --- src/security_selinux.c | 23 ++++++++++++++++------- 1 files changed, 16 insertions(+), 7 deletions(-) diff --git a/src/security_selinux.c b/src/security_selinux.c index 0db9f49..f1e3f17 100644 --- a/src/security_selinux.c +++ b/src/security_selinux.c @@ -323,6 +323,8 @@ SELinuxSetFilecon(virConnectPtr conn, const char *path, char *tcon) VIR_INFO("Setting SELinux context on '%s' to '%s'", path, tcon); if (setfilecon(path, tcon) < 0) { + int setfilecon_errno = errno; + if (getfilecon(path, &econ) >= 0) { if (STREQ(tcon, econ)) { freecon(econ); @@ -331,14 +333,21 @@ SELinuxSetFilecon(virConnectPtr conn, const char *path, char *tcon) } freecon(econ); } - virSecurityReportError(conn, VIR_ERR_ERROR, - _("%s: unable to set security context " - "'\%s\' on %s: %s."), __func__, - tcon, - path, - virStrerror(errno, ebuf, sizeof ebuf)); - if (security_getenforce() == 1) + + /* if the error complaint is related to an image hosted on + * an nfs mount, then ignore it. + * rhbz 517157 + */ + if (setfilecon_errno != EOPNOTSUPP) { + virSecurityReportError(conn, VIR_ERR_ERROR, + _("%s: unable to set security context " + "'\%s\' on %s: %s."), __func__, + tcon, + path, + virStrerror(errno, ebuf, sizeof ebuf)); + if (security_getenforce() == 1) return -1; + } } return 0; } -- 1.6.2.5

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[libvirt] [PATCH] spec file: add URL to Source tag
by Mark McLoughlin 21 Aug '09

21 Aug '09

See https://fedoraproject.org/wiki/Packaging:SourceURL --- libvirt.spec.in | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/libvirt.spec.in b/libvirt.spec.in index dad97ec..00c394c 100644 --- a/libvirt.spec.in +++ b/libvirt.spec.in @@ -81,7 +81,7 @@ Version: @VERSION@ Release: 1%{?dist}%{?extra_release} License: LGPLv2+ Group: Development/Libraries -Source: libvirt-%{version}.tar.gz +Source: http://libvirt.org/sources/libvirt-%{version}.tar.gz BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-root URL: http://libvirt.org/ BuildRequires: python-devel -- 1.6.2.5

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[libvirt] error: failed to connect to the hypervisor
by Dominik Klein 21 Aug '09

21 Aug '09

Hi I am running kvm-78 with libvirt 0.6.1 and see the following error from time to time when my linux-ha cluster tries to run "virsh domstate" to figure out a virtual machine's state: error: failed to connect to the hypervisor In syslog, I see: libvirtd: 23:39:11.357: error : Failed to set close-on-exec file descriptor flag Due to this error, the cluster assumes the machine is not running okay and reboots it in order to fix things. This happened twice in 2 months with 10 machines being queried like that each minute (read: not too well reproducable) What is this and how could I work around it or is this fixed in newer versions and so worth an upgrade? Regards Dominik

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[libvirt] Migration fail
by Christian Hennig 20 Aug '09

20 Aug '09

hi, i am trying to migrate a VM from my local system "pc38" to a remote on "pc36": virsh # list --all Id Name State ---------------------------------- - scalaris1 shut off virsh # migrate scalaris1 qemu+ssh://csr-user@pc36/system error: monitor socket did not show up.: No such file or directory What is the monitor socket? Both system are ubuntu server 9.04 : christian@pc38:~$ virsh --version Connecting to uri: qemu:///system 0.6.1 christian@pc38:~$ Thx for help! Christian

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