Install guide

The public network is the pathway used by the application tier to access the database. The failure
scenario is the loss of an entire node, so although bonding does provide protection in the event of the
public interface failure, this is not as likely. Bonded public interfaces complicate application tier network
configuration and failover sequencing. This network is not bonded in our example.
The hostnames of the server nodes are identified by the public address. All other network interfaces are
private, but they still may need addresses assigned by network operations.
RAC/GFS Considerations
Oracle Clusterware (CRS) creates it’s own set of Virtual IPs (VIP) on the public interface. T his
mechanism makes it possible for CRS on another node to provide continued access to the failed
node’s specific public address. Bonded public interfaces, in the presence of CRS VIPs, are not
recommended. See Oracle SQL*Net Configuration in both the HA and RAC/GFS Chapters.
3.3.2. Red Hat Cluster Suite Network
The Red Hat Cluster Suite network is used by CMAN to monitor and manage the health of the cluster.
This network is critical to the proper functioning of the cluster and is the pathway that is bonded most
often.
RAC/GFS Considerations
RAC requires GFS clustered file systems, which utilize the Distributed Lock Manager (DLM) to
provide access to GFS. The Oracle Global Cache Services (GCS) is often configured to use this
pathway as well. There is a risk of overloading this network, but that is very workload dependent.
An advanced administrator may also choose to use Infiniband and Reliable Data Sockets (RDS)
to implement GCS.
The network is private, and only ever used by cluster members. T he dual-ported e1000 NIC is used for
the Red Hat Cluster Suite hearbeat service or Oracle RAC Clusterware services.
The file /etc/modprobe.conf contains all four interfaces, and the two ports of the e1000 will be
bonded together. The options for bond0 set the bond for failover (not load balance), and the sampling
interval is 100ms. Once the file modprobe.conf file is modified, either remove and reload the e1000
kernel module, or the modification will take effect at the next reboot.
alias eth0 tg3
alias eth1 tg3
alias eth2 e1000
alias eth3 e1000
alias bond0 bonding
options bond0 m ode=1 m iimon=100
The configuration of the bond requires three network-scripts files: One for bond0, and then the
corresponding interface files have to be set as well, as shown in the following example.
Red Hat Enterprise Linux 5 Configuration Example - Oracle HA on Cluster Suite
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