Domain Name Server (DNS) environment
Multi-Homed CommCell® Computers
WINS or other Non-DNS Environment
All CommCell® computers (i.e., CommServe, MediaAgent, and Client computers) must be connected via a network configured with TCP/IP protocol. To ensure each computer can resolve the names of other CommCell computer members and therefore communicate, we offer the following guidelines.
A DNS environment provides a centralized means of resolving computer names with their corresponding IP addresses. Refer to your operating system documentation for information on how to establish and manage DNS.
A multi-homed computer is one that has two or more network interface cards (NICs). To ensure proper name/IP address resolution within the CommCell computer, it is necessary to uniquely name each NIC in the DNS. For example, assume there is a computer whose computer name is amber and fully qualified host names are amber1.company.com and amber2.company.com respectively. This computer has two NICs with the following IP addresses:
To ensure that both interfaces can be resolved, define unique names within DNS, such as:
If a computer name resolves to multiple IP addresses, the software will automatically use the first IP address resolved. However, if that first IP address becomes unreachable, the software will not be able to reach the computer using the other IP addresses in the list. In such scenarios, it is recommended that a hosts file be created with all the computer's reachable IP addresses included. |
If your network does not have DNS lookup or some other name resolution facility, the CommServe® manager will provide the names and IP addresses of all the members in the CommCell® group. The fully qualified computer name and IP address of the CommServe manager is stored in the hosts file of each CommCell member. The hosts file in the CommServe computer, in turn, stores the fully qualified computer name and IP addresses of all the members in the CommCell, thereby providing the lookup facility to all the members in the CommCell group. Depending on the operating system on your computer, the hosts file is located in one of the following directories:
During installation of each CommCell member, the install program attempts to resolve the name of the CommServe manager to an IP address. If the resolution fails, the installation prompts you to enter the IP address of the CommServe computer.
Proper name/IP address resolution is essential to reliable network communications. |
Prior to performing any installation, ensure that the hostname and the fully qualified domain name are reachable from the CommCell network, and the IP Addresses/Host Names are resolved correctly using the DNS System.
Computers in a network use the Domain Name System to determine the IP address associated with a host/domain name. This process is also known as forward DNS resolution. Reverse DNS lookup is the inverse process, the resolution of an IP address to its designated host/domain name. For a proper network communication, the IP Address to Host Name resolution and Host Name to IP address resolutions are essential.
If reverse DNS lookup is not enabled on a client computer, it will not be able to communicate with the remote computer by using the host name.
Use the following steps to perform a reverse lookup on an IP address:
nslookup <remote_computer_ip_address>
Example:
C:\administrator.idclab\nslookup 172.xxx.xxx.244
Server: ingpdc01.gp.cv.company.com
Address: 172.16.xxx.xxx
Name: faraday.gp.cv.company.com
Address: 172.xxx.xxx.244
In the above example, the first section specifies the server and the IP address of that server that provided you with the domain name, and the second section shows the host name associated with the IP address that you typed with nslookup command.
If the DNS service is not running on the setup, the above command returns one of the following error messages:
No Response from Server
Timed Out
No Records
Server Failure
Use the following steps to enable Reverse DNS lookup on a client computer:
In case the DNS is not configured or not supported, then the client computer will not be able to perform IP/Name resolution and will not be able to communicate with the remote computers by using the host names. You can overcome this temporarily by adding the IP addresses and the fully qualified domain names in the host file of the client computer. It is not recommended to add Hosts file entries as these create communications control points that may impact other server operations and are difficult to maintain and manage. These should be used only as temporary solutions until the larger network or DNS issues can be resolved. You can use the following steps to add entries to the host file of the client computer with Windows operating system:
Example:
172.32.xxx.xxx dbwin1.idclab.loc dbwin1
172.14.xxx.xxx dbwin2.idclab.loc dbwin2
Similarly, to enable reverse lookup on a remote computer, repeat step 1 through step 3 for adding IP address of the client computer in the hosts file of the remote computer.
For more information, see: http://technet.microsoft.com/en-us/library/cc780585(WS.10).aspx
For a Unix computer, the entries should be added in the host file located under etc folder.
CommCell® computers can operate on the following Internet Protocol (IP) versions:
The CommServe® computer requires IPv4 to obtain permanent licenses. However, the CommServe® computer can have both IPv4 and IPv6 enabled using multiple NIC cards. If the client computers in the CommCell® use the IPv6 protocol, the CommServe and MediaAgent must also use the IPv6 protocol.
To enable CommCell® functionality for Windows computers on an IPv6 network, you must use the following registry keys:
Note that this key only provides IPv6 support for the duration of the software installation.
To enable CommCell functionality for Unix computers on an IPv6 network, you must perform the following:
-display-interface-family [nPreferredIPFamily]
For example, if you wish to apply both IPv4 and IPv6 support, you would add the following to the cvpkgadd command:
-display-interface-family 0
Note that this key only provides IPv6 support for the duration of the software installation.
-Djava.net.preferIPv6Addresses=true
For example:
"C:\Program Files\Java\jre1.6.0\bin\javaw.exe" -jar cv.jar cranberry 8401 -oemid=1 -Djava.net.preferIPv6Addresses=true
Note that this configuration is supported for the CommCell Console as a stand-alone application only. If you are running the CommCell Console as a remote web-based application, you will always obtain an IPv4 address.
/tmp/cvpkgadd_unlock_ipaddress
Therefore, it is recommended that the services handling stub file restores are running before accessing offline stub files on a Celerra file server from a Windows computer with IPv6 enabled.
IPv6 is not supported for the following:
Additionally, consider the following: