PowerHA SystemMirror and virtual Ethernet

The PCI Hot Plug utility in PowerHA SystemMirror is not applicable to interfaces on a virtual Ethernet. This utility only handles physical interface cards. Because virtual Ethernet uses virtual I/O adapters, you cannot use the utility.

The following list contains additional considerations for PowerHA SystemMirror with virtual Ethernet:

• If VIOS has multiple physical interfaces defined on the same network, or if there are two or more PowerHA SystemMirror nodes using VIOS in the same frame, PowerHA SystemMirror will not be informed of (and therefore will not react to) single physical interface failures. This does not limit the availability of the entire cluster because VIOS routes traffic around the failure. VIOS support is analogous to EtherChannel in this regard. Use methods that are not based on VIOS to provide notification of individual physical interface failures.
• If VIOS has only a single physical interface on a network, then PowerHA SystemMirror detects a failure of that physical interface. However, the failure will isolate the node from the network.
  Note: In VIOS 2.2.0.11, or later, you can use storage area network (SAN) communication between logical partitions by establishing a virtual local area network through a virtual Ethernet adapter on each VIOS client. You can set up SAN communication through VIOS for both NPIV and vSCSI environments.
• In a VIOS environment, failure of the physical network adapter and network components outside the virtualized network might not be detected reliably. To detect external network failures, you must configure the netmon.cf file with one or more addresses outside of the virtualized network.

Troubleshooting virtual Ethernet connections

To troubleshoot virtual Ethernet interfaces defined to PowerHA SystemMirror and to detect an interface failure, treat these interfaces as interfaces defined on single adapter networks.

In particular, list the network interfaces that belong to a VLAN in the etc/cluster/ping_client_list or in the PING_CLIENT_LIST variable in the /usr/es/sbin/cluster/etc/clinfo.rc script and run the clinfo program. This way, whenever a cluster event occurs, the clinfo program monitors and detects a failure of the listed network interfaces. Due to the nature of VLAN, other mechanisms to detect the failure of network interfaces are not effective.