Planning for IP address takeover on XD networks

Edit online

IP Address Takeover via IP aliases is the default method for IP label and address recovery in PowerHA® SystemMirror®, and it is enabled in GLVM for PowerHA SystemMirror Enterprise Edition by default.

XD_data networks with IP Address Takeover via IP aliases must have a service IP label that falls over between nodes in the cluster. Clients outside of the cluster can use this service IP label. This IP address is associated with the primary instance of a resource group, and can be moved via aliasing between nodes at the same site or across sites.

Since an IP address at one site may not be valid at the other site because of subnet issues, you can configure site-specific service IP labels to handle this situation.

Site-specific service IP labels are only activated when their resource group is online primary on the specified site. The service IP label can fall over to other nodes on the specified site. Except for the site-specific limitation, these service IP labels have all the same functions as regular service IP labels, except the ability to work with NFS cross-mounts between the sites.

For more information on configuring networks and IP labels, see Administering PowerHA SystemMirror.

Planning for XD_data Networks

An XD_data network type is used by geographically mirrored volume groups in a PowerHA SystemMirror cluster for transferring the data between the RPV devices. To plan for the XD_data networks, consider the following.
  • In GLVM for PowerHA SystemMirror Enterprise Edition, you can have up to four XD_data networks in the cluster.
  • Estimate the required network bandwidth for each XD_data network.
  • IP Address Takeover via IP aliases is enabled by default for XD_data networks.

    Plan to assign persistent node IP labels on each node that is part of the network.

    Include an alias service IP label for clients to access and decide whether to make this a site-specific service IP label.

    Note: If you do not want any IP Address Takeover, you must convert the network type to private.

Planning for the XD_ip Networks

An XD_ip network type is used for heartbeating between nodes and across sites. The XD_ip network has IP Address Takeover via IP aliases enabled by default. You must assign an alias IP service label on the network. You can decide whether to make this a site-specific service IP label.