Welcome Overview Up and Running Technical Assistance Support Links Site Map     updated: 4/10/98 Terrie Beloin

MacDNS Up & Running page 2 of 3 Information Required for Setup Installation Configuring the MacDNS server Configuring clients Using other MacDNS features Configuring the MacDNS Server Verify TCP/IP connectivity Make sure MacTCP or TCP/IP is properly configured, as described in the Installation instructions. Test a Web Browser from the machine, to confirm that it is configured properly, communicating over the network, and that your server is able to resolve domain names by communicating with the parent name server (second entry in your TCP/IP control panel's "Name Servers" field). If you're not connected to an ISP yet, or for whatever reason have no other name service available, use a ping utility of some kind (such as MacTCP Watcher, freeware available on the Internet) to ping other IP devices on your LAN. Create a Zone File The part of the Internet domain name space for which your MacDNS server contains information is called its zone of authority. You need to provide your MacDNS software with details about your particular zone. Select New Zone File... from the File Menu. Define basic zone information in the Zone Information window. In this window modify only the Domain Name, Primary Server and Administrator fields. Leave the Secondary Server entry blank until the server is fully configured.   For example: Leave the refresh interval, the retry interval, the expire interval and the Minimum Time-to-Live (TTL)* value at the recommended defaults (these fields are described in the MacDNS administrator's guide and the DNS Primer included in this module). When done, Click OK, and SAVE. *Optional tip: If desired, change the time-to-live (TTL) value here (the minimum value which will apply to all hosts in this zone), and in your host records, to a very short period of time (a number of seconds) until you can verify the MacDNS configuration. The TTL value indicates how long host information may be cached by other name servers; if information is entered incorrectly (for example, if you transpose two numbers in entering a host's IP address), corrections won't be seen by other name servers until their cached information expires and they query the MacDNS server again. Once you've verified configuration for your hosts, you can increase the TTL values again. At this point you should get a blank Zone Window (it will be titled with the domain name). Once you create hosts for your domain, they will appear in this window, also referred to as the Hosts List Window.   The first entry to make is a Permanent Host entry for the computer MacDNS is running on. Select Add Permanent Host... from the Hosts Menu.         Set the machine name to the same as the Primary Server name from the Zone Information window, ex: asip.acme.com Enter the machine's IP address. Enter any Aliases for this machine (ex. www.acme.com and ftp.acme.com) (Optional) If this host is your mail server, or a primary server at your site to which mail might be directed, then type mail exchanger information in the Mail Exchangers text box; each entry you type must consist of a numeric preference value, followed by a space, then the name of the host that will either process or forward mail for the host that you are adding. The mail exchangers are hosts to which mail may be sent for ultimate delivery to the mail server itself (see the DNS Primer section on Mail Exchangers for an example of how this would work.) The preference value indicates the mail exchanger’s priority; the lower the number, the greater the preference. The value itself isn’t important, as long as the number for the mail exchanger that you want to be used first is lower than than the values for any other mail exchangers you’ve entered. Multiple entries must be separated by a comma. The following example indicates the correct format for an entry that includes two mail exchangers: 10 mail.acme.com, 20 mail.myISP.com Note that when entering mail exchangers, you must use the name of the permanent host, not its aliases. (See also the appendix of the MacDNS Administrator's guide for more details about mail exchangers). (Optional) Configure Hardware and Software type. Our sample permanent host would look like this: We would use the same procedure for setting up our second permanent host, the mail server: Notice that mail.acme.com still requires a Mail Exchanger pointing back to itself. When mail is being sent to teb@mail.acme.com, the DNS server will need to ask of mail.acme.com, essentially "who does your mail?". The response is given from the Mail Exchanger fields. So the information would pass that mail.acme.com handles its own mail, i.e., it is a mail server itself. Most people want their mail to be addressable to them at their domain name, for simplicity. For example, I want people at Acme to have an email address of user@acme.com. But "acme.com" is only my domain, it's not the name of a particular host. So next, we need to create MX only Host that is the same name as the domain name, and enter the same Mail Exchanger preferences used above. Select Add MX-Only Host... from the Hosts menu, and enter the information, as displayed below. Now, when mail is addressed to teb@acme.com, the DNS queries will ask who handles mail for acme.com? It will receive a reply of "mail.acme.com" and "mail.myISP.com". It will then ask for the mail exchangers of mail.acme.com, and will then try to send the mail to mail.acme.com. If for some reason mail.acme.com is not responding, the mail will go to the second preference, which is a mail server at my ISP's, with whom I've made arrangements for mail forwarding. That mail server will continue to attempt to forward the mail to mail.acme.com. Now use the Look Up Host function in the Window Menu to verify that the entries in this zone are functioning correctly. Note that these lookups are being done within the application itself; they are not queries being sent to the name server listed in the TCP/IP control panel. Note that CNAME stands for Canonical Name, or "alias." Once you've verified that lookups are successful, select Set Parent Servers from the Hosts menu to configure the Parent Servers. This will allow lookups outside the zone(s) for which this machine is authoritative; in this case, any name outside of the acme.com domain. In our example (and in many cases), a name server at the ISP is used. Whenever our MacDNS server gets a lookup request for a name that is not in the "acme.com" domain, it will send the request to the parent server to resolve. It will then cache the address for a period of time (the TTL, or time to live value), in case its requested again. Once again use Look Up Host to verify that MacDNS is now able to lookup other entries. (ex. www.apple.com or www.ibm.com). In order to verify that users on the Internet will access this DNS server use the "whois mydomain.com" command to check InterNIC delegation. This can be done using a web interface to Whois (try http://rs.internic.net/cgi-bin/whois). If the domain name is found, information will be returned showing the name of the site that has that domain name registered, contact information, and IP addresses for the name server--in this case, your MacDNS server--that has authority over that domain. Once everything checks out you can go back to the Zone Information window and enter the name of the secondary server (if any). The secondary server will receive and import data from this server, and can act as a backup to this server. (As mentioned earlier, MacDNS does not support importing data, so to use it as a secondary server, the zone files would need to be moved from the primary to secondary, and opened at the secondary with the "Open Zone File..." command under the "File" menu.) Basic configuration is complete. If you want to add another zone, to handle another domain, simply repeat the process from the beginning. Otherwise, move on to configuring the local clients to use MacDNS as their primary name server.   Configuring Clients Using Open Transport If using the TCP/IP control panel on clients, you'll configure it so that the MacDNS machine is the first name server in the list, followed by the ISP's name server, and after that, whatever other name servers you may have (for example, your ISP's secondary name servers). Remember that , with Open Transport, queries are sent to the name servers in the order given. Using Classic Networking (MacTCP) If using MacTCP (part of "Classic Networking"), the configuration would be somewhat different. MacTCP allows you to associate a domain with a particular name server. The MacTCP configuration would look something like this: acme.com 192.10.10.2 . 192.10.10.2 . 192.10.20.2 . 192.10.20.3 In this example, queries about a host in the "acme.com" domain would be sent to 192.10.10.2 (our local MacDNS server). All other queries (the "." represents the top level, or essentially "any domain name") would first be sent to 192.10.10.2, again, our local MacDNS server, who may have the data cached, and if not, who will send the query to the parent mail server at our ISP: 192.10.20.2 If for some reason our local MacDNS server is not responding (for example, if its temporarily down for maintenance), then all queries will go to our ISP's mail server at 192.10.20.2 And, just in case that name server is also down for some reason, we can try the ISP's secondary mail server at 192.10.20.3. <back to top> [ Welcome | Overview | Up&Running | Tech Assist | Support | Links | | SiteMap |