OCFS2 Integration with HP Serviceguard for Linux Administrator's Guide, First Edition, November 2008

A minimum of three network interface cards. However, it is preferable to use four or

more network interface cards.

—

— Shared storage device.

• Configuration Requirements

— At least one public network interface for clients to access the nodes. For availability,

this must be configured as a bonded network using an additional network card.

— Two network interface cards configured as a private network with Linux channel

bonding for OCFS2 data and Serviceguard Heartbeat.

Figure 2-1 is a sample configuration with 4 nodes and 3 LUNs. The number of nodes and LUNs

required will vary depending on your environment.

Figure 2-1 Configuration Scenario

To Public Network

Node 1 Node 4

Node 2 Node 3

Shared

Storage

LUN 1 LUN 1 LUN 1

eth0

eth2 eth2

eth1 eth1

eth0eth0 eth0

Figure 2-1 shows a four node cluster comprising Node 1, Node 2, Node 3 and Node 4 configured

to run both HP Serviceguard for Linux and OCFS2. Three LUNs are exposed from a shared

storage to all the four nodes through Fibre Channel links. Each of the nodes require at least three

network interface cards. OCFS2 requires a dedicated LAN for intra-cluster communication and

the high availability for that LAN is handled with Linux channel bonding.

Following is the manner in which the network is configured:

• eth2 — This is the public network interface through which clients will connect to the cluster

nodes.

• eth0 and eth1 (bond0) — These are a pair of channel bonded network interfaces used for

internal OCFS2 communication and HP Serviceguard heartbeat. OCFS2 does not support

independent redundant network connections. As a workaround, multiple network interfaces

can be bonded using Linux channel bonding and presented to OCFS2 as a single interface.

HP Serviceguard must be configured to send heartbeat only on this bonded interface. Multiple

individual heartbeat networks for HP Serviceguard is not supported in this integrated

environment as Serviceguard needs to see the same heartbeat failure that is seen by OCFS2.

This bonding is the only way to achieve heartbeat redundancy.

14 Integrating OCFS2 with HP Serviceguard for Linux