Prerequisites for xHA - BlueCat Address Manager - 8.3.2

Address Manager Administration Guide

prodname
BlueCat Address Manager
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8.3.2
Before you create an xHA pair in Address Manager, make sure you have completed the following prerequisites:
  • You must have at least two connected and managed DNS/DHCP Servers in the configuration running software version 8.1.1 or greater.
  • DNS/DHCP Servers must be either two physical appliances or two virtual machines. Mixed xHA pairs of appliance and VM are NOT supported.
  • Both DNS/DHCP Servers must be at the same software version before creating an xHA pair.
  • Both DNS/DHCP Servers must be of the same profile, such as two DNS/DHCP Server 60 or two DNS/DHCP Server 100 profiles. For details on adding servers, refer to Adding DNS/DHCP Servers to Address Manager.
  • Both DNS/DHCP Servers must be of the same architecture, That is, two 64-bit servers, or two 32-bit servers (such as two XMB2 appliances).
    Attention: Cross-architecture xHA pairs, such as one 64-bit node and one 32-bit node, are NOT supported.
  • In order to create an xHA pair with the Active node on which the dedicated management interface enabled, the dedicated management interface on the Passive node must be enabled.
  • The Active and Passive nodes must be on the same network.
  • xHA with IPv4 only: no IPv6 addresses must be present on either the Active or Passive nodes.
  • xHA with IPv4 and IPv6: both the Active and Passive Nodes must be configured with only one IPv6 address. Configuring multiple IPv6 addresses may prevent successful creation of xHA.
  • The servers for the xHA pair must not be associated with a deployment schedule. For information on viewing the servers in a deployment schedule, refer to Deployment schedules.
  • The server intended for the passive role must not be associated with a deployment role. For instructions on how to view the deployment roles assigned to a server, refer to Viewing Deployment Roles.
  • Remove any old certificates and create identical time settings on both servers.
  • Attention: To avoid split-brain scenarios (where both servers are active or passive at the same time), the use of xHA Backbone Communication is mandatory.
    • When configuring the xHA Backbone for DNS/DHCP Server xHA, it is important that the IPv4 addresses of the xHA interfaces (eth1) are not on the same subnet as the Service interface (eth0) and non-routable IP’s. For DNS/DHCP Servers with dedicated management enabled, the IPv4 addresses of the xHA interface must be on a difference subnet as the Management interface (by default, eth2).
    • If you are currently using the xHA/eth1 ports for another purpose, you can reset and then reconfigure them for xHA communication, but you cannot use the eth1 ports for xHA communication and for their previous purpose.
    • If you are upgrading from an earlier version of DNS/DHCP Server software, you must delete each eth1 port to reset it. Previous versions of DNS/DHCP Server software did not support eth1, and eth1 is not reset automatically.
    • Make sure to configure the IPv4 address of the xHA interface (eth1) on a different subnet than any other interface. This is the recommended best practice for direct xHA Backbone connections and connections over switches or wide area networks (WAN).
Attention:
  • If you are currently using the xHA/eth1 ports for another purpose, you can reset and then reconfigure them for xHA communication, but you cannot use the eth1 ports for xHA communication and for their previous purpose.
  • If you are running an xHA pair with xHA Backbone communication configured over switches or WAN, make sure to configure the IPv4 address of eth1 on a different subnet than eth0 and eth2.
  • If you are upgrading from a previous version of DNS/DHCP Server software, you must delete each eth1 port to reset it. Previous versions of DNS/DHCP Server software did not support eth1, and eth1 is not reset automatically.
  • Do not try to configure half-duplex communication. If you try to configure half-duplex, DNS/DHCP Server prevents you from saving the setting and an error message appears. For more information about duplex settings contact https://care.bluecatnetworks.com.
  • To be sure of reliable xHA service, use NTP to control the time on both servers.
  • You cannot use xHA with Anycast; they are mutually exclusive.
  • You must set the Server Identifier DHCP service option if serving DHCP from xHA pairs configured with VLAN interfaces. For details, refer to DHCP with VLAN and xHA.