$ doas fw_update
By default, there are only four tap interfaces. We need to create sufficient devices for all our virtual machines:
# cd /dev
# for i in $(jot 50 4 50); do sh MAKEDEV tap$i; done
We need to increase arpq because we may have so many virtual machines on the same switch:
# sysctl net.inet.ip.arpq.maxlen=1024
# echo "net.inet.ip.arpq.maxlen=1024" >> /etc/sysctl.conf
We will need to permit IPv4 and IPv6 forwarding for our virtual machines:
# sysctl net.inet.ip.forwarding=1
# echo "net.inet.ip.forwarding=1" >> /etc/sysctl.conf
# sysctl net.inet6.ip6.forwarding=1
# echo "net.inet6.ip6.forwarding=1" >> /etc/sysctl.conf
Next we must create /etc/hostname.bridge0:
add if0
where if0 is the interface device.
We edit /etc/vm.conf:
socket owner :vmdusers
switch "switch0" {
interface bridge0
}
vm "user123" {
owner user123
memory 512M
cdrom "/home/iso/install69.iso"
disk /home/user123/user123.qcow2
interface {
locked lladdr aa:bb:cc:dd:ee:01
switch "switch0"
}
}
WARNING: Do not use aa:bb:cc:dd:ee:xx. Make sure to choose your own random lladdr. However, make sure not to pick a broadcast MAC address. If the first octet of the address is an odd number (such as f1:xx:xx:xx:xx:xx or f3:xx:xx:xx:xx:xx), it will appear as a broadcast device and may be the cause of routing issues. Networking will no longer work as a result.
Next we will need to download our ISO for OpenBSD.
$ doas useradd -m -g =uid -c "iso" -d /home/iso -s /sbin/nologin iso
$ ftp https://cdn.openbsd.org/pub/OpenBSD/7.0/amd64/install70.iso
$ ftp https://cdn.openbsd.org/pub/OpenBSD/7.0/amd64/SHA256.sig
$ signify -C -p /etc/signify/openbsd-70-base.pub -x SHA256.sig install70.iso
Signature Verified
install70.iso: OK
$ doas mv install70.iso /home/iso/
$ doas mv SHA256.sig /home/iso/
$ doas chown -R iso:iso /home/iso/
If the signature does not verify, don't proceed.
We will want to enable and start vmd:
$ doas rcctl enable vmd
$ doas rcctl start vmd
We need to create a new group vmdusers for each of our users so they can access the serial console:
# groupadd vmdusers
# chown root:vmdusers /var/run/vmd.sock
For each virtual machine, we create a user and a disk image using install.pl:
$ ./install.pl
# vmctl create -s 20G user.qcow2
You will need to add this crontab entry for a user to prevent the networking from timing out:
For openbsd:
@reboot /usr/bin/tmux new -d 'while true; do /sbin/ping -i5 38.87.162.1; done' \;
If some users are using the wrong IPs, you can run tcpdump with the -e flag to show the lladdr of tcp packets.