Tuning the Cluster Interconnect - Expert Oracle RAC Performance Diagnostics and Tuning - page 469

Linear Scalability of Private Interconnect
As mentioned earlier in this chapter, in Oracle Database 11g Release 2 (11.2.0.2), Oracle has enhanced the private
interconnect configuration and now allows multiple IPs to be configured as private interconnects.
This is compared to the traditional method of providing redundancy to the NIC configurations using bonding/pairing
and so forth where only one NIC is used at any given time. The new HAIP feature provides load balancing and close
to linear scalability to the network component, as additional private networks are added to the configuration.
The following output illustrates where a single private NIC is configured on the cluster; the output also illustrates
that Oracle stores this information in the GPnP profile instead of the OCR (as done in the previous releases of Oracle):
Script:MVRACPDnTap_verifyic.sql
SELECT addr,
indx,
inst_id,
pub_ksxpia,
picked_ksxpia,
name_ksxpia,
ip_ksxpia
FROM x$ksxpia;
Impl
ADDR Indx Public Type Name IP Address
---------------- ------ ---------- ---------- ---------- ---------------
00002B8010E5AA10 0 N GPnP eth23:1 169.254.240.242
SELECT inst_id,
name,
ip_address,
is_public
FROM gv$cluster_interconnects
ORDER BY inst_id;
Instance Name IP Address IS_PUBLIC Source
-------- ---------- --------------- --------- --------------------
1 eth23:1 169.254.240.242 NO
2 eth23:1 169.254.170.5 NO
Figure 14-9 illustrates the traffic across a single interconnect configured in a RAC cluster, with an average load of
114/028 kbits/sec, averaging about 1,800 packets/sec. This is pretty much the kind of load average expectancy when
NIC bonding or pairing is configured for high availability of the interconnect. In this case of bonding (illustrated in
Table 14-4 ), irrespective of the number of NICs that are bonded together at any given point in time, only one NIC is
really being used.