Redundant Interconnect with Highly Available IP (HAIP) 简介
从11.2.0.2开始，Oracle 的集群软件Grid Infrastructure(GI)中新增了Redundant Interconnect with Highly Available IP(HAIP)，以实现集群私网的高可用性和负载均衡。
在11.2.0.2之前，私网的冗余一般是通过在OS上做网卡绑（如bonding, EtherChannel等）实现的，有了HAIP之后，无需使用网卡绑定就可以实现私网网卡的冗余。
在安装GI的过程中，可以定义多个私网网卡来实现私网的冗余，如图：
安装后，HAIP地址自动设置为169.254.*.*,这个地址不可以手动设置。HAIP 最少为１个，最多为４个(1块网卡，1个HAIP;2块网卡，2个HAIP; 3块及以上，4个HAIP), 均匀的分布在私网的网卡上。
案例：
1. 查看HAIP资源状态
$ crsctl stat res -t -init
NAME
TARGET STATE SERVER STATE_DETAILS Cluster Resources
-------------------------------------------------------------------------------------------------
ora.cluster_interconnect.haip
ONLINE ONLINE node2
2.查看HAIP地址和分布情况。
#ifconfig -a
eth1 Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:192.168.254.32 Bcast:192.168.254.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe4b:b766/ Scope:Link
UP BROADCAST RUNNING MULTICAST MTU: Metric:
......
eth1: Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:169.254.31.199 Bcast:169.254.127.255 Mask:255.255.128.0 <=====HAIP address one.
UP BROADCAST RUNNING MULTICAST MTU: Metric:
Interrupt: Base address:0x1800
eth2 Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:192.168.254.33 Bcast:192.168.254.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe4b:b770/ Scope:Link
UP BROADCAST RUNNING MULTICAST MTU: Metric:
......
eth2: Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:169.254.185.222 Bcast:169.254.255.255 Mask:255.255.128.0 <=====HAIP address two.
UP BROADCAST RUNNING MULTICAST MTU: Metric:
Interrupt: Base address:0x1880
haip均匀的分布在两个私网网卡上。
3. 断掉网卡eth1之后
eth2 Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:192.168.254.33 Bcast:192.168.254.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe4b:b770/ Scope:Link
UP BROADCAST RUNNING MULTICAST MTU: Metric:
RX packets: errors: dropped: overruns: frame:
TX packets: errors: dropped: overruns: carrier:
collisions: txqueuelen:
RX bytes: (1.4 MiB) TX bytes: (2.7 MiB)
Interrupt: Base address:0x1880
eth2: Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:169.254.185.222 Bcast:169.254.255.255 Mask:255.255.128.0 <=====HAIP address two.
UP BROADCAST RUNNING MULTICAST MTU: Metric:
Interrupt: Base address:0x1880
eth2: Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:169.254.31.199 Bcast:169.254.127.255 Mask:255.255.128.0 <=====HAIP address one. 网卡一eth1的HAIP漂移到eth2上
UP BROADCAST RUNNING MULTICAST MTU: Metric:
Interrupt: Base address:0x1880
HAIP one 漂移到了网卡eth2上。
4. 网卡eth1恢复之后。
eth1 Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:192.168.254.32 Bcast:192.168.254.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe4b:b766/ Scope:Link
UP BROADCAST RUNNING MULTICAST MTU: Metric:
......
eth1: Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:169.254.31.199 Bcast:169.254.127.255 Mask:255.255.128.0 <=====HAIP address one. HAIP又回来了
UP BROADCAST RUNNING MULTICAST MTU: Metric:
Interrupt: Base address:0x1800
eth2 Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:192.168.254.33 Bcast:192.168.254.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe4b:b770/ Scope:Link
UP BROADCAST RUNNING MULTICAST MTU: Metric:
......
eth2: Link encap:Ethernet HWaddr :0C::4B:B7:
inet addr:169.254.185.222 Bcast:169.254.255.255 Mask:255.255.128.0 <=====HAIP address two.
UP BROADCAST RUNNING MULTICAST MTU: Metric:
Interrupt: Base address:0x1880
HAIP one 回到了网卡eth1上。
注意：HAIP地址失败不会对ocssd产生影响，也就是说HAIP失败，不会导致节点重启。
HAIP 对数据库和ASM的影响
数据库和ASM实例使用这个HAIP作为cluster interconnect,以下是alert.log的片段。
Cluster communication is configured to use the following interface(s) for this instance
169.254.31.199
169.254.185.222
cluster interconnect IPC version:Oracle UDP/IP (generic)
IPC Vendor proto
Oracle数据库和ASM实例可以通过HAIP来实现私网通讯的高可用性和负载均衡。私网的流量会在这些私网网卡上实现负载均衡，
如果某个网卡出现了故障，它上面的HAIP会自动切换到别的可用的私网网卡上，从而不影响私网的通讯。
注意：HAIP 是不允许被手动停止或禁用的，除非是由于某些版本或者平台不支持。
关于HAIP的更多介绍，请参考My Oracle Support Note 文档1210883.1.
以上文章整理自：