Ok, setting up back to back machines should be simple, right? So mostly so, but sometimes I do everything right and some f-ing ethernet cable is busted and has me questioning which file i forgot to change. So here you go:

• edit /etc/nsswitch.conf to have 'hosts' and 'ipnodes' look for 'files' before DNS/NIS/etc.
• make up some fake IP addresses and hostnames - say 10.x.x.y (client-b2b) and 10.x.x.y+1 (server-b2b), add those to /etc/hosts and /etc/inet/ipnodes on both the client and server
• add a line to /etc/netmasks (with the above fake IPs, '10.x.x.0 255.255.255.0' would work)
• create a /etc/hostname.[interface name][interface number] -- for me, i'm using a v20z and it has a dual port internal bge interface, so i create /etc/hostname.bge1 (since /etc/hostname.bge0 already exists), and fill it with the b2b machine name ("server-b2b" or "client-b2b" in this example)
• Hook up your cable, Reboot both machines

Now let's check the client:

Note, that if bge1 isn't 'RUNNING' then something is probably wrong.

Now, let's make sure it worked:

Woo wee! and yes the 10.x.x.y, a.b.c.d, and ether addresses are all totally bogus.