Hi, 2 weeks ago I had some problems with X on Solaris 10. I decided to reinstall the system today.

The problem I have now is with networking.

I've changed the configuration of my computers. They are connected through a router, with each computer having a unique ip.
The computer running solaris should have:
I guess it should be in /etc/networks but in which form?

thanks

btw, what's the solaris equivalent of linux's ifup/ifdown and the name of the first NIC?

In LQ there's plenty of information about IP services configuration.
There's no /etc/networks file in solaris, I suggest you read Sun documentation, man pages and read LQ threads, too. The files you're looking for are:

TCP/IP configuration in Solaris is done in the following files:
/etc/hostname.{interface} <- there should be one for every NIC you want the system to plumb (associate a device to it) during solaris boot
/etc/nodename
/etc/defaultdomain
/etc/defaultrouter (optional)
hosts database
netmasks database (optional)

That's very good documentation in Sun Microsystems's "System Administration Guide: IP services" that you can download at docs.sun.com.

Hope this helps.

thanks, I'll read it

A couple of files to complement cristosomo_enrico's answer:

/etc/resolv.conf contains dns client configuration
/etc/nsswitch.conf tell the system to use dns (or other) for name resolving