<html> <head> <meta content="text/html; charset=utf-8" http-equiv="Content-Type"> </head> <body bgcolor="#FFFFFF" text="#000000"> <div class="moz-cite-prefix">On 08/25/2016 05:42 AM, Vasiliy Tolstov wrote: </div> <blockquote cite="mid:CACaajQv9d8Zqbn_Bg9TBh+ZSGyAgtXHLeU+YUBzteWPZEk1bLQ@mail.gmail.com" type="cite"> 25 Авг 2016 г. 12:34 пользователь Vasiliy Tolstov <<a moz-do-not-send="true" href="mailto:v.tolstov@selfip.ru">v.tolstov@selfip.ru</a>> написал: > > 25 Авг 2016 г. 8:58 пользователь "Laine Stump" <<a moz-do-not-send="true" href="mailto:laine@laine.org">laine@laine.org</a>> написал: > > > > The linkstate setting of an <interface> is only meant to change the > > online status reported to the guest system by the emulated network > > device driver in qemu, > I need to set host side status of interface. Without this live migration with dinamic routing software (ospf with quagga or bird) bring packet drops. Because on dest interface in up state and kernel try to forward packets to it, but guest CPU is not running. </blockquote> That shouldn't be a problem, since the IPInfo isn't added to the tap device until immediately before the guest CPU is started on the destination (that's the purpose of qemuInterfaceStartDevice()). <blockquote cite="mid:CACaajQv9d8Zqbn_Bg9TBh+ZSGyAgtXHLeU+YUBzteWPZEk1bLQ@mail.gmail.com" type="cite"> Also host side status needed for easy blackhole traffic to guest ip. </blockquote> Is this something you need to do while the guest is already running? If not, then I think we don't need anything extra. <blockquote cite="mid:CACaajQv9d8Zqbn_Bg9TBh+ZSGyAgtXHLeU+YUBzteWPZEk1bLQ@mail.gmail.com" type="cite"> May be create inside the source link state attribute for host side link status? So it consistent with ip and route elements? </blockquote> If necessary, that might be the right solution, although I still think it's better to not set the tap device offline, in case it's connected to a bridge - we wouldn't want to trigger an STP forward delay. Maybe just delete (and later re-add) the IPInfo would be less disruptive? (Or it might be *more* disruptive, we'd have to try both). <blockquote cite="mid:CACaajQv9d8Zqbn_Bg9TBh+ZSGyAgtXHLeU+YUBzteWPZEk1bLQ@mail.gmail.com" type="cite"> > > > but when support for auto-creating tap devices > > for <interface type='ethernet'> was added in commit 9717d6, a chunk of > > code was also added to qemuDomainChangeNetLinkState() that sets the > > online status of the tap device (i.e. the *host* side of the > > interface) for type='ethernet'. This was never done for tap devices > > used in type='bridge' or type='network' interfaces, nor was it done in > > the past for tap devices created by external scripts for > > type='ethernet', so we shouldn't be doing it now. > > > > This patch removes the bit of code in qemuDomainChangeNetLinkState() > > that modifies online status of the tap device. > > --- > > src/qemu/qemu_hotplug.c | 15 --------------- > > 1 file changed, 15 deletions(-) > > > > diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c > > index 00e4a75..5300bc1 100644 > > --- a/src/qemu/qemu_hotplug.c > > +++ b/src/qemu/qemu_hotplug.c > > @@ -2324,21 +2324,6 @@ int qemuDomainChangeNetLinkState(virQEMUDriverPtr driver, > > if (ret < 0) > > goto cleanup; > > > > - if (virDomainNetGetActualType(dev) == VIR_DOMAIN_NET_TYPE_ETHERNET) { > > - switch (linkstate) { > > - case VIR_DOMAIN_NET_INTERFACE_LINK_STATE_UP: > > - case VIR_DOMAIN_NET_INTERFACE_LINK_STATE_DEFAULT: > > - if ((ret = virNetDevSetOnline(dev->ifname, true)) < 0) > > - goto cleanup; > > - break; > > - > > - case VIR_DOMAIN_NET_INTERFACE_LINK_STATE_DOWN: > > - if ((ret = virNetDevSetOnline(dev->ifname, false)) < 0) > > - goto cleanup; > > - break; > > - } > > - } > > - > > /* modify the device configuration */ > > dev->linkstate = linkstate; > > > > -- > > 2.7.4 > > </blockquote> </body> </html>