[libvirt-users] [virtual interface] detach interface during boot succeed with no changes
by Yalan Zhang
Hi guys,
when I detach an interface from vm during boot (vm boot not finished), it
always fail. I'm not sure if there is an existing bug. I have
confirmed with someone that for disk, there is similar behavior, if
this is also acceptable?
# virsh destroy rhel7.2; virsh start rhel7.2 ;sleep 2; virsh
detach-interface rhel7.2 network 52:54:00:98:c4:a0; sleep 2; virsh
dumpxml rhel7.2 |grep /interface -B9
Domain rhel7.2 destroyed
Domain rhel7.2 started
Interface detached successfully
<address type='pci' domain='0x0000' bus='0x00' slot='0x06'
function='0x0'/>
</controller>
<interface type='network'>
<mac address='52:54:00:98:c4:a0'/>
<source network='default' bridge='virbr0'/>
<target dev='vnet0'/>
<model type='rtl8139'/>
<alias name='net0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03'
function='0x0'/>
</interface>
When I detach after the vm boot, expand the sleep time to 10, it will succeed.
# virsh destroy rhel7.2; virsh start rhel7.2 ;sleep 10; virsh
detach-interface rhel7.2 network 52:54:00:98:c4:a0; sleep 2; virsh
dumpxml rhel7.2 |grep /interface -B9
Domain rhel7.2 destroyed
Domain rhel7.2 started
Interface detached successfully
-------
Best Regards,
Yalan Zhang
IRC: yalzhang
Internal phone: 8389413
2 years, 3 months
Set hostname of guest during installation time
by john doe
Hi,
I would like to set the hostname when installing a guest, with the below
command the hostname is not set to 'try06' in the guest:
virt-install --name=try06 --graphic none --pxe --network bridge=virbr0
How can I set the hostname of the guest during installation time?
I realy appriciate the support I'm getting in here, I'm fairly new to
libvirt.
--
John Doe
4 years, 1 month
guest-fsfreeze-freeze freezes all mounted block devices
by Marc Roos
I wondered if anyone here can confirm that
virsh qemu-agent-command domain '{"execute":"guest-fsfreeze-freeze"}'
Freezes all mounted block devices filesystems. So if I use 4 block
devices they are all frozen for snapshotting. Or just the root fs?
4 years, 4 months
[libvirt-users] Question about disabling UFO on guest
by Bao Nguyen
Hello everyone,
I would like to ask a question regarding to disable UFO of virtio vNIC in
my guest. I have read the document at https://libvirt.org/formatdomain.html
*host*
The csum, gso, tso4, tso6, ecn and ufo attributes with possible
values on and off can be used to turn off host offloading options. By
default, the supported offloads are enabled by QEMU. *Since 1.2.9 (QEMU
only)* The mrg_rxbuf attribute can be used to control mergeable rx buffers
on the host side. Possible values are on (default) and off. *Since 1.2.13
(QEMU only)*
*guest*
The csum, tso4, tso6, ecn and ufo attributes with possible
values on and off can be used to turn off guest offloading options. By
default, the supported offloads are enabl
ed by QEMU.
*Since 1.2.9 (QEMU only)*
Then I disabled UFO on my vNIC on guest as the following configuration
<devices>
<interface type='network'>
<source network='default'/>
<target dev='vnet1'/>
<model type='virtio'/>
<driver name='vhost' txmode='iothread' ioeventfd='on' event_idx='off'
queues='5' rx_queue_size='256' tx_queue_size='256'>
*<host gso='off' ufo='off' />*
*<guest ufo='off'/>*
</driver>
</interface>
</devices>
Then I reboot my node to get the change effect and it works. However, can I
disable the UFO without touching the host OS? or it always has to disable
on both host and guest like that?
Thanks,
Brs,
Natsu
4 years, 4 months
Could you please help with questions about the net failover feature
by Yalan Zhang
Hi laine,
I have leave some questions on IRC, but my VPN broken time after time.
Please ignore the questions on IRC.
In my understanding, the standby and primary hostdev interface may be in
different subnet.
I'm not sure whether it is correct. Could you please help to explain? Thank
you in advance.
For example, primary hostdev is connected to vf-pool with <pf='eth0'/>,
while the standby is connected to NAT network with " forward dev='eth0'".
The standby interface will get ip as 192.168.122.x, but after NAT, it will
be in the same subnet of the vf.
So after the VF is unplugged, the packet will still broadcast in the same
subnet, and the vm will get the packet as the standby share the same mac.
Right?
Thank you!
-------
Best Regards,
Yalan Zhang
IRC: yalzhang
4 years, 5 months
qemu hook: event for source host too
by Guy Godfroy
Hello, this is my first time posting on this mailing list.
I wanted to suggest a addition to the qemu hook. I will explain it
through my own use case.
I use a shared LVM storage as a volume pool between my nodes. I use
lvmlockd in sanlock mode to protect both LVM metadata corruption and
concurrent volume mounting.
When I run a VM on a node, I activate the desired LV with exclusive lock
(lvchange -aey). When I stop the VM, I deactivate the LV, effectively
releasing the exclusive lock (lvchange -an).
When I migrate a VM (both live and offline), the LV has to be activated
on both source and target nodes, so I have to use a shared lock
(lvchange -asy). That's why I need a hook event on the source host too
(as far as I know after my tests, the migration event is only triggered
on the target host).
Is such a feature a possibility?
Thanks for your attention.
Guy Godfroy
4 years, 6 months
Migrate to a bigger disk possible?
by Paul van der Vlis
Hello,
I have a qcow2 disk what needs to become increased.
I don't have space on the location where it is now to have it two time,
so I want to live-migrate it to another host.
On the other host I have to create a qcow2 disk before I can migrate.
What would happen when I would create there a bigger qcow2 disk then the
original one? Can I resize the filesystem after the migration?
With regards,
Paul van der Vlis
--
Paul van der Vlis Linux systeembeheer Groningen
https://www.vandervlis.nl/
4 years, 6 months
