If DNS is in use in your network, the Windows workstation you use to install ZfS components to servers throughout your network must have access to a DNS name server. In addition, the servers where you install ZfS components must have valid entries in DNS.
If you have a NATed (Network Address Translation) environment, a recipient may or may not be able to reply (depending on the routes available back to the sender), because Internet routers will drop packets having destinations of 10.x.x.x, 172.16.x.x, or 192.168.x.x.
IMPORTANT: DNS names are not required for installing ZfS in a NetWare-only environment. However, if there is even one Windows, Linux, or Solaris server in your network environment, DNS is required for installing ZfS.
If you are not already familiar with DNS, review the following terminology:
fully qualified domain name (FQDN): A server name that includes a list of all domains in the path from the local domain to the root; for example, server47.provo.novell.com.
forward lookup: Resolves an FQDN into its IP address.
reverse lookup: Resolves an IP address into its FQDN.
ping: The NetWare, Windows, or UNIX* command that accesses DNS to test whether a specified FQDN or IP address can be resolved. Refer to your operating system documentation for additional information about this command.
Do not use an underscore (_) character in the DNS name of a server. Because underscore characters are not supported in the DNS RFC, DNS name servers cannot resolve names that include underscores. Some ZfS components do not work if there is an underscore character in the DNS name of a server.
However, NetWare supports FQDNs with underscore characters if the IP-to-FQDN resolution is listed in the SYS:\ETC\HOSTS file. Reverse resolution does not occur correctly unless the IP and its corresponding FQDN are listed in the HOSTS file.
When you insert the -HOSTS switch (required for multi-homed machines) into the TED.NCF file, all host names or IP addresses resolving to an FQDN with underscore characters must be listed in the SYS:\ETC\HOSTS file.
The following sections help you test your system for DNS functionality and help you resolve any problems that you discover during testing:
In order to access DNS, a workstation must be enabled for DNS name resolution and be configured to locate a valid DNS name server.
From the workstation, ping the servers where you want to install ZfS components. Specify the servers' DNS host names, not their IP addresses. If the servers do not respond to the ping command, the workstation might not be configured for DNS. Continue with Enabling a Windows Workstation for DNS Name Resolution .
In order for a workstation to perform DNS name resolution, DNS must be selected in the Protocol Component Settings list on the Novell Client Protocol Preferences properties tab.
For example, on Windows NT:
In the Control Panel, double-click Network > click Services.
Select Novell Client for Windows NT > click Properties.
Click Protocol Preferences > make sure that DNS is checked in the Protocol Component Settings box.
A workstation cannot perform DNS name resolution successfully unless it has access to a DNS name server specified on the Internet Protocol (TCP/IP) DNS properties tab.
For example, on Windows 2000:
In the Control Panel, double-click Network and Dial-up Connections.
Double-click Local Area Network > click Properties.
Select Internet Protocol (TCP/IP) in the components list > click Properties.
On the General tab, you can choose to let the workstation obtain the DNS name server IP address automatically, or you can specify one or more DNS name server IP addresses manually. For additional DNS configuration options, click Advanced > DNS.
Select Novell Client for Windows 2000 in the components list > click Properties.
Click Protocol Preferences > make sure that DNS is listed in the Protocol Component Settings box.
Review the following sections to make sure that a NetWare server is configured properly for DNS:
From the NetWare server console, ping that server's own FQDN. For example:
ping nwserver47.provo.novell.com
If the ping returns an IP address, forward lookup is functioning. If there is no response from the NetWare server, see Configuring a NetWare Server for DNS .
From a Windows workstation, ping the NetWare server's IP address. For example:
ping -a 123.45.67.89
If the ping returns a DNS host name, reverse lookup is functioning. If there is no response from the NetWare server, see Configuring a NetWare Server for DNS .
On the NetWare server, check the SYS:\ETC\RESOLV.CFG file to make sure the information it contains is correct.
For more information about DNS on NetWare, see DNS/DHCP Services.
Review the following sections to make sure that a Windows server is configured properly for DNS:
On the Windows server, ping that server's own IP address. For example:
ping -a 123.45.67.90
If the ping is successful, the domain is configured correctly for that server. If there is no response from the Windows server, see Configuring a Windows Server for DNS .
On Windows server A, ping the FQDN of Windows server B. For example:
ping winserver5.provo.novell.com
If the ping returns an IP address, forward lookup is functioning. If there is no response from the Windows server, see Configuring a Windows Server for DNS .
On Windows server B, ping the IP address of Windows server B. For example:
ping -a 123.45.67.91
or
nslookup 123.45.67.91
If the ping returns a DNS host name, reverse lookup is functioning. If there is no response from the Windows server, see Configuring a Windows Server for DNS .
Make sure that the Windows server's DNS short name is exactly the same as the server name. Also make sure that the Windows server has a DNS suffix.
To check the server name and DNS suffix:
Right-click My Computer > click Properties > Network Identification.
The Full Computer Name field displays the server name (for example, winserver5), followed by its DNS suffix (for example, provo.novell.com) if one has already been provided.
If the server name does not match the server's DNS short name:
If the Full Computer Name field does not include a DNS suffix:
Reboot the Windows server to put the new server name information into effect.
Check the \WINNT\SYSTEM32\DRIVERS\ETC\HOSTS file to make sure that the information listed in it is correct. For example, you must have a "localhost" entry pointing to 127.0.0.1, which the facilitator requires for communicating with ZWS.
For more information about DNS on Windows, refer to Windows online help about using the DNS administrative tool.
Review the following sections to make sure that a Windows server is configured properly for DNS:
From the UNIX server, ping that server's own FQDN. For example:
ping unxserver25.provo.novell.com
If the ping returns an IP address, forward lookup is functioning. If there is no response from the UNIX server, see Configuring a UNIX Server for DNS .
From a Windows workstation, ping the UNIX server's IP address. For example:
ping -a 123.45.67.100
Or from the UNIX server, use:
nslookup 123.45.67.100
If the ping returns a DNS host name, reverse lookup is functioning. If there is no response from the UNIX server, see Configuring a UNIX Server for DNS .
On the UNIX server, make sure that the /etc/hosts file has the correct IP address and FQDN for itself. Make sure that the loopback address line (127.0.0.1) reads localhost.localdomain, not the server's FQDN.
For more information about DNS on UNIX, refer to your UNIX operating system documentation.