1General 2-------- 3 4virtio-console as the name implies is a console over virtio transport. Here is 5a simple head to head comparison of the virtio-console vs regular 8250 console: 6 78250 serial console: 8 9 - Requires CONFIG_SERIAL_8250=y and CONFIG_SERIAL_8250_CONSOLE=y kernel configs, 10which are enabled almost everywhere. 11 - Doesn't require guest-side changes. 12 - Compatible with older guests. 13 14virtio-console: 15 16 - Requires CONFIG_VIRTIO_CONSOLE=y (along with all other virtio dependencies), 17which got enabled only in recent kernels (but not all of them). 18 - Much faster. 19 - Consumes less processing resources. 20 - Requires guest-side changes. 21 22Enabling virtio-console 23------------------------ 24 25First, make sure guest kernel is built with CONFIG_VIRTIO_CONSOLE=y. Once this 26is done, the following has to be done inside guest image: 27 28 - Add the following line to /etc/inittab: 29 'hvc0:2345:respawn:/sbin/agetty -L 9600 hvc0' 30 - Add 'hvc0' to /etc/securetty (so you could actually log on) 31 - Start the guest with '--console virtio' 32 33Common errors 34-------------- 35 36Q: I don't see anything on the screen! 37A: Make sure CONFIG_VIRTIO_CONSOLE=y is enabled in the *guest* kernel, also 38make sure you've updated /etc/inittab 39 40Q: It won't accept my username/password, but I enter them correctly! 41A: You didn't add 'hvc0' to /etc/securetty 42