hi, all: my xml define interface as following: <interface type='ethernet'> <mac address='00:04:00:41:03:11'/> <model type='e1000'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> when run the command: bash-4.1# virsh start root-vsys_v77 error: Failed to start domain root-vsys_v77 error: Unable to open /dev/net/tun, is tun module loaded?: No such file or directory is my xml define error ? how can create my vm with nic driver e1000 ? bash-4.1# libvirtd -v ,yum install libvirt 2020-01-02 10:00:49.261+0000: 8349: info : libvirt version: 4.5.0, package: 23.el7 (CentOS BuildSystem <http://bugs.centos.org>;, 2019-08-09-00:39:08, x86-02.bsys.centos.org) 2020-01-02 10:00:49.261+0000: 8349: info : hostname: NSG 2020-01-02 10:00:49.261+0000: 8349: warning : virGetHostnameImpl:719 : getaddrinfo failed for 'NSG': Name or service not known 2020-01-02 10:00:49.263+0000: 8349: info : libvirt version: 4.5.0, package: 23.el7 (CentOS BuildSystem <http://bugs.centos.org>;, 2019-08-09-00:39:08, x86-02.bsys.centos.org) 2020-01-02 10:00:49.263+0000: 8349: info : hostname: NSG 2020-01-02 10:00:49.263+0000: 8349: info : virObjectNew:248 : OBJECT_NEW: obj=0x5605a6104de0 classname=virAccessManager 2020-01-02 10:00:49.263+0000: 8349: info : virObjectNew:248 : OBJECT_NEW: obj=0x5605a60f54e0 classname=virAccessManager my emulator is qemu-3.0 ,i download qemu source code and compiled the emulator: bash-4.1# /usr/local/bin/qemu-system-x86_64 --version QEMU emulator version 3.0.0 Copyright (c) 2003-2017 Fabrice Bellard and the QEMU Project developers thanks !