QEMU error: Could not set up host forwarding rule 'udp:127.0.0.1:664-:664'

[Tommy-git2033]

Hi, Guys:
i am following the guide: [https://github.com/openbmc/docs/blob/master/development/dev-environment.md]

Normally, i often run the first one, but today i want to use "devtool deploy-target" to deploy my modifications to the running machine(this machine i runed it on QEMU),
i run the second one :
./qemu-system-arm -m 256 -machine romulus-bmc -nographic -drive file=./tmp/deploy/images/romulus/obmc-phosphor-image-romulus.static.mtd,format=raw,if=mtd -net nic -net user,hostfwd=:127.0.0.1:22-:22,hostfwd=:127.0.0.1:443-:443,hostfwd=tcp:127.0.0.1:80-:80,hostfwd=tcp:127.0.0.1:2200-:2200,hostfwd=udp:127.0.0.1:623-:623,hostfwd=udp:127.0.0.1:664-:664,hostname=qemu
but i get the error return:
`qemu-system-arm: Could not set up host forwarding rule 'udp:127.0.0.1:664-:664'

anyone could help me?

[geissonator]

On most systems, you can't take the actual ports, which is why the directions encourage you to use a virtual port when starting QEMU. i.e. make it hostfwd=udp:127.0.0.1:6664-:664 and then use the 6664 port for your 664 traffic to your QEMU session. Or if you want, try running with sudo.