From 1251b881646ea754fc074626925d77a0d0e359ec Mon Sep 17 00:00:00 2001 From: Guofang Date: Thu, 1 Oct 2026 00:47:00 +0800 Subject: [PATCH] Disable QEMU's default NIC in the Debian and Fedora launchers A [netdev] in a -readconfig file does not stop QEMU from adding its default NIC, so the guests had a second user-mode network without the SSH port forward. Both NICs got 10.0.2.15 over DHCP, and SSH only worked on boots where the forwarded NIC won the race for the default route. Removing the default NIC shifts the other PCI devices down one slot, so existing VMs may need their UEFI variable store reset to boot again. Co-Authored-By: Claude Opus 5.5 --- run-debian13.py | 3 +++ run-fedora44.py | 3 +++ 2 files changed, 6 insertions(+) diff --git a/run-debian13.py b/run-debian13.py index 85d7ed1..b44eb11 100755 --- a/run-debian13.py +++ b/run-debian13.py @@ -265,6 +265,9 @@ qemu_args = [ "-readconfig", str(qemu_arch_config), # "max" is the host CPU under KVM/HVF and the fullest model under TCG. "-cpu", "max", + # The config file's [netdev] does not stop QEMU from adding its default + # NIC, a second user network without the SSH port forward. + "-nic", "none", "-display", display_backend, ] diff --git a/run-fedora44.py b/run-fedora44.py index cd5049f..c461685 100755 --- a/run-fedora44.py +++ b/run-fedora44.py @@ -267,6 +267,9 @@ qemu_args = [ "-readconfig", str(qemu_arch_config), # "max" is the host CPU under KVM/HVF and the fullest model under TCG. "-cpu", "max", + # The config file's [netdev] does not stop QEMU from adding its default + # NIC, a second user network without the SSH port forward. + "-nic", "none", "-display", display_backend, ]