Questions[virt-manager](server)

OS is Debian 10, vagrant provider is libvirt.

vagrant global-status is supposed to provide information on all vms on a system, but I can see shutoff and running vms in virt-manager that are not listed by vagrant global-status. I have only used libvirt for Vagrant so I know Vagrant is the culprit.

How do I determine the associated directory/Vagrantfile for each of these vms?

I think this command would do the trick:

find / -name Vagrantfile -exec echo {} \; -exec bash -c 'cd "$(dirname {})" && vagrant status | grep -E shutoff\|running' \; 2>/dev/null

But it seems absurd that something like this would be necessary, and would take a very long time on a large filesystem.

How exactly can I determine the directory for the associated Vagrantfile for each vm? There must be an easier way besides exhaustively searching the filesystem.

I'm having frequent network connectivity failures under the QEMU/KVM/virt-manager stack on openSUSE Leap 15.1. I have a single VM running a software firewall, which is losing connectivity every few days, taking down internet connectivity as a result. I am at a loss as to how to troubleshoot this as there is no evidence of hardware faults and nothing helpful in either dmesg or journalctl to go on.

The host has two physical NICs, one of which is physically connected to my ISP's CPE (modem) and is logically connected to the firewall VM via macvtap. The other physical NIC connects to my internal network and is logically connected to the host and the firewall VM via a bridge. The bridge provides Internet connectivity to the host.

Normally, this configuration works fine. However, on a seemingly random basis, either the bridge or the macvtap link stops transferring data to the VM. I have not lost both links at the same time; only one link fails at once so far. The host does not lose internal connectivity over the bridge nor does running ethtool on the host show show loss of physical link.

Restarting the firewall inside the VM does not restore connectivity. I have to "power off" and restart the VM through virt-manager to make the VM's network links work again.

As far as I can tell, something in the qemu-kvm-etc stack simply stops delivering packets to the VM.

The only relevant report in journalctl is when NetworkManager detects the loss of Internet connectivity (i.e. "NetworkManager state is now CONNECTED_SITE") due to the firewall VM losing connectivity but there is nothing leading up to this entry.

I have noticed that VM connectivity failures are sometimes proceeded by the host end of the bridge losing IPv6 support. For whatever reason, the bridge interface spontaneously loses all of its IPv6 addresses (including link local) despite IPv6 being enabled. When this happens, the bridge also stops passing IPv6 traffic to the VM even though IPv4 continues to work for a little while.

Any suggestions on how to approach this?

I have a hypervisor which uses kvm and virt-manager to handle the virtual machines.

The hypervisor has 6GByte of memory.

If I add a new virtual machine I don't know how much memory is still free.

At least the virt-manager dialog does not show it:

Is there a tool which helps me to find a matching maximum value?

Example:

• 6 GB total host memory
• 2 GB given to host "host-one"
• ? GB for host "host-two".

Above is only a simple example. On our real servers we have much more virtual-hosts.

I am afraid to give too much memory to the virtual-hosts. This results in heavy performance impact if the hypervisor has too few. If I would give "host-two" 4GB, then the hypervisor would be "on fire", since it has "no air to breath".

Is there a tool which can help me to decide how much memory is available?

I use this command:

virt-install -r 1024 --vcpus=2 --accelerate --nographics -n test -f test.img --cdrom /iso/CentOS.iso

but I doesn't show the text based install:

boot: linux text
Loading vmlinuz.................................
Loading initrd.img..............................................................
................................................................................
...................................
Ready.ÿ

It hangs at Ready.ÿ

any ideas?

Thanks

I'm having a bit of trouble connecting to my virtual machine host, which is an Ubuntu server running KVM/Libvirt. I can connect to the server using an Ubuntu client and I can connect via virsh on a Fedora 16 client. Unfortunately, connecting via virt-manager fails with the error: "unable to open a connection to the libvirt management daemon".