How to set static IP under OpenBSD ?

[bsd007]

How to set static IP under OpenBSD ?

$ ifconfig                                                                 
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 32768
        index 3 priority 0 llprio 3
        groups: lo
        inet6 ::1 prefixlen 128
        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3
        inet 127.0.0.1 netmask 0xff000000
re0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        lladdr 60:45:cb:87:53:a5
        index 1 priority 0 llprio 3
        groups: egress
        media: Ethernet autoselect (100baseTX full-duplex,rxpause,txpause)
        status: active
        inet 192.168.0.100 netmask 0xffffff00 broadcast 192.168.0.255
enc0: flags=0<>
        index 2 priority 0 llprio 3
        groups: enc
        status: active
pflog0: flags=141<UP,RUNNING,PROMISC> mtu 33136
        index 4 priority 0 llprio 3
        groups: pflog
udav0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> mtu 1500
        lladdr 00:e0:4c:53:44:58
        index 5 priority 0 llprio 3
        media: Ethernet none

I want to set static IP on udav0 namely IP Address, subnet mask, default gateway and dns servers.

[jggimi]

FAQ 6 (http://www.openbsd.org/faq/faq6.html) gives an overview of networking configuration. Briefly:

• IP address and netmask are set via ifconfig(8) command, and are provisioned permanently via a hostname.if(5) file. You would name this file /etc/hostname.udav0.
• A default static route is set in the mygate(5) file. This won't be applicable to your environment, as you use DHCP with the re(4) NIC. Individual routes are set with the route(8) command, added to the hostname.if(4) file for provisioning on boot. Please see the hostname.if(5) man page for an example of adding a route() command.
• Domain name resolution is system-wide, not by individual NIC. It is set via the resolv.conf(5) file. This file is replaced every time your re(4) NIC obtains a new lease from the local DHCP server, so editing the file directly will not be helpful. You can supersede settings, such as the address(es) of domain name servers, by creating a dhclient.conf(5) file, or you can create a resolv.conf.tail(5) file which will be appended to /etc/resolv.conf each time a new DHCP lease is obtained.

Please note: Your re(4) and udav(4) NICs cannot be used on the same IP network at the same time. To use both at the same time, they must be on different networks. There are two exceptions to this rule: carp(4) and trunk(4) are designed to share a single IP address over multiple NICs.

Additionally, with two different ISPs and two NICs on different networks, you might want to explore Equal Cost Multipath Routing, as described in the FAQ chapter mentioned above.