libvirtd[num]: Failed to open file '/sys/class/net/veth7a03557/operstate': No such file or directory

I want to install virt-manager and kvm, I done it but when I write

It shows me error below sudo systemctl status libvirtd.service

jūn 11 12:04:25 intelli5 libvirtd[916]: Failed to open file '/sys/class/net/veth7a03557/operstate': No such file or directory
jūn 11 12:04:25 intelli5 libvirtd[916]: unable to read: /sys/class/net/veth7a03557/operstate: No such file or directory
jūn 11 12:04:43 intelli5 libvirtd[916]: Failed to open file '/sys/class/net/veth4342446/operstate': No such file or directory
jūn 11 12:04:43 intelli5 libvirtd[916]: unable to read: /sys/class/net/veth4342446/operstate: No such file or directory
jūn 11 12:05:27 intelli5 libvirtd[916]: Failed to open file '/sys/class/net/veth09791a3/operstate': No such file or directory
jūn 11 12:05:27 intelli5 libvirtd[916]: unable to read: /sys/class/net/veth09791a3/operstate: No such file or directory
jūn 11 12:05:44 intelli5 libvirtd[916]: Failed to open file '/sys/class/net/veth86ee9f3/operstate': No such file or directory
jūn 11 12:05:44 intelli5 libvirtd[916]: unable to read: /sys/class/net/veth86ee9f3/operstate: No such file or directory
jūn 11 12:06:29 intelli5 libvirtd[916]: Failed to open file '/sys/class/net/veth101ebe9/operstate': No such file or directory

However, status is Active: active (running)

How can I fix these errors?

first of all these (gladly) are usually non fatal errors. There is some detail in this bug and it seems to mostly come from adding+renaming devices (which most network backends do automatically these days).

There are fixes available:

> 72d99b094b Avoid unnecessary error messages handling udev events
> abbd3a3184 node_device_udev: handle move events

Those are in libvirt v6.3.0 and thereby in Ubuntu 20.10 and later. Since this is a non critical issue it doesn't really qualify for an SRU. So if they annoy you really hard you could consider an upgrade or alternatively think about using server-backports.