Wazza s Snow Leopard Server QuickStart 2. Configuring DNS About this Document This document is the second in a series of documents describing the process of installing and configuring a Mac OS X 10.6 Server for use in a school environment. Other documents in this series are available at: servernotes.wazmac.com This document describes the initial DNS configuration of a newlyinstalled Mac OS X Snow Leopard Server. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 1
Other documents in this series Installing & setting up the Mac OS X Server Software Initial software Installation and config. Configuring DNS (This document) adjusting the default setup, checking zones, adding machines. Setting up Services - 1 Services overview Setting up Services - 2 AFP, Web & SMB (Windows) Setting up Services - 3 DHCP Setting up Services - 4 Open Directory Setting up Sharepoints - 1 Groups folder Home directories Setting up Users and Groups Setting up Sharepoints - 2 Imaging folder Group folder permissions Client Imaging - Creating a master image - Creating a NetBoot image - Configuring NetBoot - Preparing the Server - Deploying a master image Managing Preferences Connecting from Windows XP - WorkGroup Configuring Mac OS X Server as a Primary Domain Controller (PDC) Connecting OS X Clients to Open Directory Backing up your Server Configuring your Intranet Enabling Blogs and Wikis Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 2
1. DNS Configuration 1.1. Working on the server directly, or using ARD or Screen Sharing from a remote computer, check the network settings of the server in System Preferences > Network. If the server is to be the DNS server for the network, check that the DNS Server entry is the IP address of the server, and that the Search Domain entry is correct for your local network. 1.2. Working on the server directly, or using Server Admin Tools installed on a remote computer, open Server Admin. Server Admin Tools can be installed from the disk accompanying the server installation software, or downloaded from - support.apple.com/downloads. 1.3. If not already listed in the pane on the left, double-click on the entry in the Available Servers list to connect to the server. The server may be identified as either it s local network name, or it s fully qualified domain name, or an IP address. The services that you enabled in the previous setup procedure will be listed with a green button. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 3
1.4. On the left of the main Server Admin window, expand the server s services list and select the DNS service. 1.5. Click on the Zones icon at the top of the right pane of the Server Admin DNS window. 1.6. You will be warned that changing the settings may cause some services to be lost. Click on the OK button and continue. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 4
1.7. As we noted in the previous Installation & Setup document, the server installation process creates a default internal DNS setup on the server, so that basic services can function. We are going to create a new Primary Zone and a new Reverse Zone, then delete the default option that was setup by the installation process. 1.8. Click on the Zones button at the top of the window. 1.9. Click on the Add Zone button at the bottom of the right pane, then choose Add Primary Zone. 1.10. In the bottom half of the right window enter your local zone information - this is just the zone (or domain) name, and does not include the name of the actual server. eg - somewhereps.edu.au. Leave the Fully Qualified button ticked - and add a trailing. to the zone name. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 5
1.11. Click the + button to add a nameserver, in the bottom half of the window. The name of the server should be entered automatically. Click on the Save button. 1.12. Select the newly added Primary Zone. Click on the Add Record button, and choose to Add Machine. 1.13. In the bottom half of the window edit the information about the new machine - enter your server s name and IP address. Click your cursor in one of the blank fields to make sure that the information you enter sticks. Click on the Save button. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 6
1.14. The addition of the New Machine record in the new Primary Zone will have created another Reverse Zone in the top half of the window. 1.15. Now - we need to select the original Primary zone, and the original Reverse Zone (those entries that were configured automatically by the server). The original Reverse Zone will have a four-digit reverse IP address (possibly with the numbers of a DHCP distributed address.) The original Primary Zone will include the name of the server, rather than just the zone/domain name. 1.16. With the original entries selected, click on the Remove button to delete them. 1.17. That should leave you with only the name of the newly added Primary Zone and Reverse Zone. Click on the Save button. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 7
1.18. Click on the Stop DNS button at the bottom of the window. 1.19. You will be warned that stopping DNS may interrupt some services. 1.20. Click the Start DNS button to restart the DNS. Stopping and starting the DNS ensures that the current settings are loaded by the service. Note: If you receive a message at any stage of this process that no server exists at the chosen address, choose to Remove the server, then choose to Add a new server, using the IP address of the server. (Server Admin > Server menu.) I have found that using the server s IP address is more reliable in the event that DNS is playing up. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 8
2. Checking the server s host name When you change the zone information above, using Server Admin s GUI, the information that you enter is written to some under-the-hood config files. To check that the new information that you have entered has been correctly updated in these config files it is worth checking using the Terminal application. 2.1. Open Terminal in the Application > Utilities folder. (If it is not already there, drag it to the Dock). 2.2. Type the following command: sudo changeip -checkhostname 2.3. Press the Return key on your keyboard, and you will be asked to enter your Root password. This is most likely the same as your admin password (unless you have changed it!) 2.4. Press the Return key again to see the results of your hostname check. 2.5. Hopefully you will see the success entry. If not, you may need to start over with your server install. It is that critical. And re-installing at this stage is probably faster than troubleshooting! Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 9
3. Adding DNS Forwarders In DNS terms, your server only knows about itself, because that s the only info we have entered in the DNS admin records. So that you server can resolve the addresses of other domains for which it may receive requests from web browsers on your local network, we need to tell it to forward these requests to a parent DNS server. The parent servers are usually the DNS servers of your ISP or educational organisation. 3.1. Click on the Settings button at the top of DNS window in Server Admin. 3.2. Add the relevant primary and secondary Forwarder IP Addresses. (These addresses may have already been added automatically from another local server, if one is available.) If you have made any changes to the Forwarder IP Addresses, click on the Save button, then Stop and Start the DNS. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 10
4. Network Settings Now that the server is supplying a Domain Name Service, we need to check that it is configured to use these settings. 4.1. Working directly on the server, or via Screen Sharing or Apple Remote Desktop, launch the server s System Preferences and click on the Network preference. 4.2. Check that the DNS Server address is the IP address of the server and the Search Domain is the loca domain name. This information should have been entered when originally configuring the server. (If this information is not correct the DNS configuration process above may have been producing some inconsistent results.) 4.3. If required, click on the Advanced button, then on the Proxies button, and enter the proxy server information for your network s Internet access. 4.4. Click on the Apply button. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 11
5. Checking Your DNS Setup It is critical to the operation of your server that DNS is functioning correctly. Before proceeding with any further configuration we must check that DNS is working correctly, resolving forward and reverse lookups, both locally and through any parent DNS servers. 5.1. Open the Network Utility. The Network Utility is in the Applications > Utilities folder. If you do not have a Hard Disk icon appearing on your server s desktop, go to Finder > Preferences, and choose to show Hard Disks on the desktop. 5.2. Drag the Network Utility icon to the Dock for easy access in the future. 5.3. Click on the Lookup tab and enter the IP address of your Mac OS X Server. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 12
5.4. Click on the Lookup button. You should see a response that resolves the IP address to fully qualified domain name of your server... eg. server6.somewhereps.edu.au 5.5. Now enter the fully qualified domain name (FQDN) of the domain server and click the Lookup button. You should see a response that resolves to the FQDN to IP address of the server. 5.6. Success with the above indicates that the server can recognise and resolve DNS information about itself (forward and reverse lookups). Now we need to check to see if it can handle information about other servers, by passing (or forwarding) the information on to another DNS server. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 13
5.7. Enter the name of a known server on the internet (eg www.abc.net.au) You should see a response that resolves the IP address of the remote server. This resolution is made by the DNS server that you nominated as your forwarder. 5.8. If your server responds correctly to the above lookups, your DNS is configured and operating correctly. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 14
6. Other Machine-specific Additions to DNS There are likely to be a number of other local computers that you would like your DNS server to recognise, without forwarding the request to another DNS server. You can add these individually, as below: 6.1. Select the Primary Zone entry, and choose Add Machine (A) from the Add Record menu. 6.2. Select the newly-added machine entry and edit the information relating to that machine in the lower pane of the window. 6.3. Click in a blank field elsewhere in the window, and the entries at the top of the window will be updated. 6.4. Click on the Save button, then Stop and Start the DNS to enable the new information that you have entered. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 15
6.5. Software Update Check that you have internet connectivity and run Software Update. The next document in this series provides details of setting up additional services on your server. Wazza s QuickStart - OSX Server 10.6-2: Configure DNS 16