As was referred to during the installation process, IU's network is a "subnetted" network. The effect of this is that network traffic is restricted to each individual subnet of IU's network instead of traveling all over campus when communications can be restricted to just those points between the communicating devices. Each subnet at IU has a special device called a "router" which forwards network traffic that is not for a machine on this subnet but for another machine on another network. Usually, the default router at IUB has an IP number of the form 129.79.xxx.254 where "xxx" refers to the subnet number.
The Network Operations Center (NOC) at UCS, noc@indiana.edu , can tell you which router IP number is used on your particular subnet. Or call the UCS Support Center at 5-6789.
Once you know this information, you need only create a file called "/etc/defaultrouter" and place this router IP address in that file. A simple way to do this is simply to type..
echo 129.79.xxx.254 > /etc/defaultrouter...where xxx is the subnet number from the IP address.
Next, in order to have full DNS support on your workstation, you need to create the file /etc/resolv.conf. There are 4 ways to run DNS on your machine: Primary Nameserver, Secondary Nameserver, Cache-Mode Nameserver and Resolver-Mode. At IU, there are 3 Primary Nameservers and a few Secondary Nameservers. These machines provide the rest of the campus with the hostname to IP address lookup. You can not setup a primary or secondary nameserver without first talking to the Network Operations Center. You will probably never need to setup a primary or secondary nameserver. The other 2 ways are for workstations. Caching-mode namservice, gets the IP address/hostname match up and caches it. So the next time there is a request, the system does not need to go out across the network. This is a good idea for servers on your network. For most machine, resolver-mode nameserver is best. It is the simplest to setup and maintain. To setup resolver-mode nameservice, all you need is a file called /etc/resolv.conf. Please do the following:
{hostname}# cd /etc <Return> {hostname}# vi resolv.conf <Return>...and then inserting the lines...
domain ucs.indiana.edu search ucs.indiana.edu indiana.edu nameserver 198.88.18.1 nameserver 129.79.1.9...where each IP number corresponds to one of the nameservers on campus, and the domain used is the local domain for this machine, such as, math.indiana.edu.
This file is used by Solaris to help the system know where to look for information pertinent to its own functionality. When we first configured the system, we instructed the installation procedure to assume that the system would always look for pertinent information in its "/etc" files (By using Other in the Name Service Panel.) Well, for most information, this is exactly what we want to do. However, it would be impractical to keep information about all the other hosts on the network (whether at IU or on the worldwide Internet) -- primarily each host's IP address/hostname -- in the "/etc/hosts" file. Even if we did keep this information here, it would be a never ending job just to keep it up-to-date.
Instead, IU operates a several primary nameservers, that are then known by the next level in the Internet nameservers, whose function is to provide this information when your workstation requests it. This is handled by a service called DNS (for Domain Name System).
In order for your newly installed workstation to use DNS automatically, it is necessary to alter the file "/etc/nsswitch.conf" by changing the line below...
hosts: files...to read...
hosts: files dnsThis change can be made with any available file editor however, it is recommended that you become familiar with the editor called vi simply because it ships as the default editor with all versions of UNIX. Most other editors, such as "emacs" are available only as an add-on to your system.
Solaris 2.X ships with a version of the sendmail daemon installed that does not support mail exchange. You can install a new sendmail and corresponding /etc/sendmail.cf from the Unix Workstation Support Group's anonymous ftp server. Please refer to the Configuring and administrating mail topic for more information.