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.
To create a zone file with the information about your zone:
1. Choose New Zone File from the File menu. A Zone Information dialog box appears, with an untitled host list window
for the zone file underneath it.
Important: When you first see the Zone Information dialog box, its text boxes contain "templates" of the information you need to enter. You can follow the style of the template when you provide the information for your own zone. In the instructions that follow, verify the template information is selected for a particular text box, then type your own zone's information (the template text should be completely deleted or replaced).
2. In the Zone Information dialog box, type the domain name of your zone in the Domain Name box.
The domain name should be the name you've registered, as explained earlier in the section "Registering Your Domain."
3. Type the DNS name of your server computer in the Primary Server box.
Note: Verify you type a DNS name, which is different from the name you might have chosen for your computer, for Macintosh file sharing.
4. Type the name of a secondary server, for the zone, in the Secondary Server box.
A secondary server keeps a copy of your zone's information; a secondary server is useful for spreading the name-service load across multiple machines, and for ensuring that a zone has name service even if the primary server fails.
Note: MacDNS does not function as a secondary server: it only functions as the primary name server.
5. Type your email address in the Administrator box.
Your address will be useful to other administrators, who may need to contact you for help debugging problems that arise.
6. Type an amount in the Refresh Interval box, and choose a unit of time from the adjacent pop-up menu (or confirm the default value).
The Refresh Interval indicates how often a secondary server will query your MacDNS name server to see whether new information is available. If something has changed, the secondary server updates its information, updating is called a zone transfer.
- The recommended Refresh Interval is 8 hours.
7. Type an amount in the Retry Interval box, and choose a unit of time from the adjacent pop-up menu (or confirm the default value).
The Retry Interval represents the interval a secondary server will wait before reattempting to contact the MacDNS server, if the first attempt has failed.
- The recommended Retry Interval is 2 hours.
8. Type an amount in the Expire Interval box, and choose a unit of time from the adjacent pop-up menu (or confirm the default value).
The Expire Interval is the interval a secondary server will cache zone information it has already received, if the MacDNS server can't be reached to provide a zone transfer. The Expire Interval will set a time at which the zone data can no longer be regarded as up to date; after that point, the data is not considered useful, and it's better for the secondary server to provide no data than obsolete data. Once the Expire Interval limit is reached, the secondary server removes all data about your MacDNS server from its database.
- The recommended Expire Interval is 7 days.
9. Type an amount in the Minimum TTL box, and choose a unit of time in the adjacent pop-up box (or confirm the default value).
TTL represents time to live. The Minimum TTL is the minimum time to live for an entry in the MacDNS database.
- The recommended Minimum TTL is 1 day.
The following figure shows an example of a completed Zone Information dialog box:
Figure 1: Zone Information dialog box
Note: The values for the Refresh, Expire, and Minimum Intervals shows that the figure is the recommended settings for keeping your zone up to date without excessive network traffic.
10. Click OK.
After you click OK, the title of the host lists window changes to the name you entered, as the domain name, in the Zone Information dialog box. The name is preceded by a diamond until you save the zone file.
Important: To ensure you have a permanent record of the host information for your zone, be sure to save the zone file (choose Save from the File menu).
Configuring your parent server
The MacDNS server relies on other DNS servers, called parent servers, for answers to queries that it doesn't have in its own database. Generally, the MacDNS server should use the DNS server for your Internet service provider as its parent. You may also enter other servers to be alternate parents, which will be used if the first parent server isn't available.
MacDNS uses the DNS information that is configured in the MacTCP or TCP control panel to obtain a default list of parent servers. If that information has not been configured or is incorrect, you will have to configure the parent server(s) yourself.
To verify that your parent server information is correct, or to add alternate parent servers:
1. Choose Set Parent Servers from the Hosts menu.
A dialog box similar to the following one appears.
Figure 2: Parent Servers
2. Verify the default parent server information is correct; if it isn't, select the server name or the server IP address, and type the correct information.
3. If you want to add alternate parent servers, type the applicable information in the Server Name and the Server IP Address boxes.
4. Click OK.
Note: When you click OK, the new parent server information takes effect immediately; you don't need to restart the MacDNS application.
Adding hosts
To add information about a host computer:
1. Choose Add Permanent Host from the Hosts menu. The Host Information dialog box appears. The following figure shows a Host Information dialog box; note that most of the information has been entered according to the subsequent task steps in this section.
Figure 3: Host Information
2. Type the name of the host in the Host Name box. When the Host Information dialog box first appears, a "template" name
appears in the Host Name text box. The host name is the canonical or "real" name of the host. You assign this name permanently to the host. The host name must include the domain name; since the domain name is automatically included as part of the template, all you need to do is select "a-permanent-host" and type the first part of your host's name.
3. Type the IP address assigned to the host in the IP Address box.
4. Type an amount in the "Time to Live" box and choose a unit of time in the adjacent pop-up menu; or, confirm the default setting. The Time to Live indicates time that a remote DNS server can cache information about this host. The default is the minimum time-to-live value for the zone, which is usually a good choice.
5. (Optional) Type the name of aliases for this host in the Aliases text box. The names you type must be separated by commas. Each name must be a fully qualified domain name.
Note: You cannot use an alias name that does not include the domain name of the host. For example, you can use "www.company.com" for an alias of "sage.company.com", but you cannot use "www.provider.com", because "provider.com" is outside the "company.com" zone. To work around this restriction, you can create a new zone file for the "provider.com" domain and add "www.provider.com" as a permanent host. You can then assign the IP address of the "real" host machine (sage.company.com) to this host.
6. (Optional) 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 alternate hosts which mail may be sent to for ultimate delivery to this host (see the appendix for more details about mail exchangers).
The preference value indicates the mail exchanger's priority; the lower the number, the greater the preference. The value itself is not important, as long as the number for the mail exchanger that you want to be used first is lower than the values for any other mail exchangers you have 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 email.webewidgets.com, 20 Ur-mail.webewidgets.com
7. (Optional) Select the computer type for the host you're adding in the Hardware pop-up menu.
If you leave "None" selected, no computer type will be returned for host information queries from other DNS servers.
8. (Optional) Select the operating system for the host you're adding in the Software pop-up menu.
If you leave "None" selected, no operating system type will be returned for host information queries from other DNS servers.
9. Click OK.
Adding hosts that require a mail exchanger only
The MacDNS program allows you to choose hosts that need mail exchange service only and no other Internet services. If a host needs special handling of its mail delivery only, you don't need to assign an IP address, but you can assign a mail exchanger. Such hosts are called MX-only hosts.
An MX-only host is most commonly used when your domain name itself is not an actual host computer. You can use the domain name as the MX-only host name, then use the name of your local email host (and possibly your Internet service provider's email host, if you have made arrangements to do so) as the mail exchanger.
To assign a mail exchanger for an MX-only host:
1. From the Hosts menu, choose Add MX-Only Host.
The MX-Only Host Information dialog box appears.
2. Type the name of the host in the Host Name text box.
3. Type an entry in the "Time to Live" box and select a value from the adjacent pop-up menu; or confirm the default value.
The default time-to-live value is the minimum TTL for the zone, usually a good choice.
4. Type the numeric preferences and the names of hosts to act as mail exchangers in the "Mail Exchangers" text box.
Figure 4: MX-Only Host Information
Multiple entries should be separated by a comma. The lower the number you assign as a preference value, the greater the preference is for a host to act as a mail exchanger.
5. Click OK.