Volume Number: 14 (1998)
Issue Number: 3
Column Tag: Tips & Tidbits

Tips & Tidbits

by Steve Sisak

In order to run TCP/IP applications (clients and servers) without being connected to a network, a Mac still needs to be setup as if it were on a network. There are some special requirements in doing this for an unnetworked machine.

Ethernet cannot be used unless you are connected to a hub or another Ethernet device (if you are, you don't need the following method). So, you will instead have to use AppleTalk over LocalTalk (whether or not you're actually connected to a LocalTalk network). This method uses MacIP which is a way of using TCP/IP within AppleTalk.

• AppleTalk must be on. You will want it to be using LocalTalk (use the AppleTalk control panel in OpenTransport, or the old Network control panel in other systems).
• Depending on which you're using, the MacTCP or OpenTransport TCP/IP control panel has to be configured to connect using AppleTalk/MacIP.
• Set your TCP connection to AppleTalk (MacIP) or LocalTalk.
• Configure your local address to be obtained manually.
• Set your IP Address to 192.0.1.2 (class C).
• Leave the Domain Name Server fields blank (unless you are running a Domain Name Server on your mac, in which case set the fields to point to your local machine).
• Any Routing/Gateway fields should be left blank (or set to 0.0.0.0 if they must be filled in).
• In OpenTransport, click the "Select Zone..." button in the "TCP/IP" control panel and set it to "Current AppleTalk zone".
• Subnet mask and any other fields are irrelevant, so should be left at their defaults (255.255.255.0).
• MacTCP usually requires a reboot after configuration changes, OpenTransport accepts these changes on the fly.
• You will have to address server software you run on your local machine by the IP address you assigned in the TCP/IP configuration (192.0.1.2). For example, a web server would be addressed using the url "http://192.0.1.2/" from your client software.
• If you want to use domain names instead of IP addresses, you will need to configure domain names in your TCP "hosts" file. This file is found in your "System Folder". Instructions for setting up the hosts file are contained in the default "hosts" file supplied with MacTCP or OpenTransport.

Grant Neufeld,
grant@kagi.com