This weekend I\u2019ve been fiddling with<\/p>\n
QEMU<\/a>. I\u2019ve installed\u00a0OpenBSD<\/a>\u00a0on a single image and wanted to have two instances of it communicating via network. Installing the system was easy, but the networking setup was quite a pain. See how I did that\u2026 To make QEMU instances communicate with each other I needed to plug them to a \u201cnetwork\u201d. That\u2019s why I\u2019ve created a bridge to which Virtual Instances would connect to. <\/p>\n I\u2019ve used the following script: <\/p>\n Then I just needed to start Qemu with this command line:<\/p>\n\r\n#!\/bin\/bash \r\n# 1st, release all DHCP address and remove all IP address associated\r\n# with the original eth0\r\n#\/sbin\/dhcpcd -k\r\nkill
pidof dhclient<\/code>\r\n\/sbin\/ip addr flush eth0\r\n# then take the interface down so we can rename it\r\n\/sbin\/ip link set eth0 down\r\n# now rename the original eth0 to reth0 (Real ETH0)\r\nnameif reth0 00:24:81:43:61:5b\r\n# OK, bring the same interface (with new name though) back up\r\n\/sbin\/ip link set reth0 up\r\n# 2nd let's create a bridge called eth0 so other programs think they are\r\n# talking to the same old interface (actually they will talk to the\r\n# bridge which is a clone of the original eth0 - with name MAC addr)\r\n\/usr\/sbin\/brctl addbr eth0\r\n# then add both origianl eth0 and tap1 device to the bridge\r\n\/sbin\/brctl addif eth0 tap1\r\n\/usr\/sbin\/brctl addif eth0 reth0\r\necho \"showing bridge mac addresses\"\r\n\/usr\/sbin\/brctl showmacs eth0\r\n# 3rd, we need to bring the newly created bridge UP\r\n\/sbin\/ip link set eth0 up\r\n# 4th, renew the DHCP address if possible\r\n#\/sbin\/dhcpcd -n\r\ndhclient eth0\r\n\/sbin\/ip addr show\r\n<\/pre>\n\r\nsudo qemu openbsd-4.7.img -net tap -net nic,macaddr=52:54:00:12:34:57,model=ne2k_pci\r\n<\/pre>\n