Planning the Infrastructure Implementation › IPv6 Support › Configuration Considerations in Context of IPv6 Support

Configuration Considerations in Context of IPv6 Support

In context of IPv6 support in CA IT Client Manager (CA ITCM), you should observe the following configuration notes and aspects.

• Configuration parameters (policy entries) in the DSM Explorer control the IPv6 and IPv4 connections, as follows:

  Define precedence of DNS lookups

  Defines the precedence of DNS queries when performing DNS queries directly, that is, not using common functions. In pre-Windows Vista operating environments, DNS is supported over IPv4 only.

  Default: ipv4,ipv6

  Define precedence of name resolution

  Defines the order of precedence of name resolution functions. In some environments, WINS and NETBIOS name resolution may be more reliable than DNS. In these cases, you can specify that NETBIOS resolution should be used in precedence to DNS lookups.

  If this parameter is set, the value of the Use NETBIOS short name fallback configuration parameter is ignored, and the name resolution will first query NETBIOS by stripping the FQDN to a short name before falling back to try DNS and other methods. If a short-name lookup due to this policy has already been performed, the short name fallback will be skipped, if enabled. This parameter is supported only on CA ITCM systems that support NETBIOS lookups.

  Note: This parameter is not currently used.

  Default: dns,netbios

  Define precedence of resolved addresses

  Defines the precedence of the IP address family (IPv6 or IPv4), when multiple IP address families are used.

  When resolving addresses, this centrally managed parameter specifies what precedence should be applied to each address family. The default is to order IPv4 addresses before IPv6 addresses to maintain maximum interoperability.

  Default: ipv4,ipv6

  Enable IPv4 resolution

  Enables support for IPv4 address resolution. This parameter is only a placeholder in the current version of the software, and therefore end nodes will ignore the setting and always support IPv4 resolution.

  Default: True

  Enable IPv6 resolution

  Enables support for IPv6 address resolution, allowing IPv6 addresses to be returned. If disabled (False), the resolver removes any IPv6 addresses from the name resolution results.

  Note: This parameter is honored by end nodes, as opposed to the mirror IPv4 control.

  Default: True

  Use database for name resolution fallback

  Specifies a fall back to an IP address stored either on a manager's MDB database or a server's database when a live name cannot be resolved through address location services (DNS) or NETBIOS.

  Note: The default fallback option should be left as is in most cases and only changed if requested by CA technical support personnel.

  Valid values are as follows:

  1 = All fallback modes enabled

  2 = Use server database fallback

  4 = Use MDB fallback

  Default: 1

  Use NETBIOS short name fallback

  Indicates whether NETBIOS short names are used as a fallback if the fully-qualified name (FQN) lookup fails.

  Default: True

  Note: These configuration parameters are located in the Configuration Policy/Default Computer Policy/DSM/Common Components/Networking/General pane. For more detailed information, see the General Policy Group (Networking) topic in the Configuration Policy section of the DSM Explorer Help.

• If CA ITCM is installed on an IPv4 only computer, and at a later date, IPv6 is enabled, the computer should be rebooted and the CAF service restarted.
• If your network supports IPv6 only (that is, IPv4 routing has been disabled or stopped) or is predominantly using IPv6 connections, we recommend that you change the value of the "Define precedence of resolved addresses" configuration parameter to ipv6,ipv4. This setting will improve the performance of communications between the different computers in the enterprise or domain.
• If you have a manager with a remote MDB and only IPv6 routing between manager and remote MDB, opening the DSM Explorer for the first time is very slow, because the configuration parameter "Define precedence of resolved addresses" is initially set to ipv4,ipv6 by default. In this case, the name resolves first to an IPv4 address, the database connection fails after a timeout, then the IPv6 address is tried, which succeeds. The configuration policy can be changed only after the DSM Explorer opens.
• If there are a significant numbers of Windows 2003 and Windows XP computers in your network, the configuration parameter "Define precedence of DNS lookups" should be left as ipv4,ipv6, because on these platforms DNS messages are sent only over IPv4 connections.

DNS Name Resolution for Computers Hosting DSM Components

All the computers hosting the DSM components such as, enterprise manager, domain manager, scalability server, and agents must support both forward and reverse DNS lookup. Verify that the communication between the DSM components works correctly.

Assigning a Hostname to Loopback IP

CA ITCM requires that the hostname is resolvable at all times for internal and external communications. The interactive installer contains an option, Assigned hostname to the loopback IP, which allows for the former option to be set.

For unattended installation, set the write_hostname entry to True in the networking or DNS section of autoinst.xml, as follows:

<networking>
  <dns>
    <dhcp_hostname config:type="boolean" >false</dhcp_hostname>
    <dhcp_resolv config:type="boolean" >true</dhcp_resolv>
    <hostname>$HostName$</hostname>
    <write_hostname config:type=boolean>true</write_hostname>
  </dns>
</networking>

You can find the autoinst.xml file at the following location:

DSM_Install_Folder\server\SDBS\var\managedpc\images\IMAGE_NAME\IMAGE_NAME\suse