Qemu 9.2.x & Ubuntu 24.04 Network Issue
Description of problem:
After successfully starting, I cannot access the Internet with the virtual machine. I can connect to the VM via SSH and execute various commands. We want a simple NAT network..

We built the Qemu distribution ourselves with the following command:

./configure --target-list=x86_64-softmmu --disable-install-blobs --enable-strip --enable-user --enable-system --enable-linux-user --disable-xen --enable-modules --enable-module-upgrades --enable-linux-aio --enable-fdt --enable-gnutls --enable-libiscsi --enable-libssh --enable-vnc --enable-kvm --enable-vhost-user
make -j 12
sudo make install

Check Libvirt:
$systemctl status libvirtd - active

after the VM was successfully started, the IP 10.2.15 was set to ens3 altname enp0s3 assign.

A ping to 8.8.8.8 can not be resolved.
Additional information:
We can rule out an image problem because this image runs without problems on the Windows Mac guest system and an Internet connection is possible.