Database Reference
In-Depth Information
FC storage controllers. On the software side, we need to configure multipathing software to group the multiple I/O paths
together so that one I/O path can fail over I/O traffic to another surviving path in case one of the paths should fail.
This ensures that at least one I/O path is always available to the disks in the storage.
Figure
1-2
shows a example of configurating two redundant storage network connections to a SAN storage.
Depending on the storage network protocols, the storage can be linked with servers using either the FC or iSCSI
network. To achieve high I/O bandwidth of the storage connections, some high-speed storage network solutions,
such as 16GbE FC and 10gBe iSCSI, have been adapted for the storage network. The detailed configuration of shared
storage is discussed in Chapter 5.
Private Network Switch1
Private Network Switch2
LAN/WAN
Server 2
Server 4 (leaf node)
Server 1
Server 3
(hub node)
Storage Network
Private Interconnect
Public Network
Two Storage
Switches
Two Storage
Controllers
Shared SAN Storage
Figure 1-2.
Oracle RAC hardware architecture
The network configuration for an Oracle RAC configuration includes the public network for users or
applications to connect to the database, and the private interconnect network for connecting the RAC nodes in the
cluster. Figure
1-2
illustrates these two networks in a two-node RAC database. The private interconnect network is
accessible only to the nodes in the cluster. This private interconnect network carries the most important heartbeat
communication among the RAC nodes in the cluster. The network is also used by the data block transfer between the
RAC instances.
A redundant private interconnect configuration is highly recommended for a production cluster database
environment: it should comprise at least two network interface cards (NICs) that are connected to two dedicated
physical switches for the private interconnect network. These two switches should not be connected to any other
network, including the public network. The physical network cards can be bound into a single logical network using
OS network bonding utilities such as Linux Bonding or Microsoft NIC Teaming for HA and load balancing.
