RAC 某节点不可用时，对应VIP是否可用

实验环境：RHEL 6.5 + GI 11.2.0.4 + Oracle 11.2.0.4
验证：RAC 某节点不可用时，其对应VIP是否可用？是否可用于连接数据库？

[grid@jyrac2 ~]$ more /etc/hosts127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4::1 localhost localhost.localdomain localhost6 localhost6.localdomain6#public ip192.168.56.150jyrac1192.168.56.152jyrac2#private ip10.10.10.11jyrac1-priv10.10.10.12jyrac2-priv#virtual ip192.168.56.151jyrac1-vip192.168.56.153jyrac2-vip#scan ip192.168.56.160jyrac-scan

1.节点宕机，对应节点VIP漂移到另一个节点
2.节点宕机后，另一个节点的网络信息
3.可ping通宕机节点VIP，但无对应监听
4.知识点总结

1.节点宕机，对应节点VIP漂移到另一个节点

模拟主机jyrac1宕机，随之该节点的VIP资源failed over。
此时在主机jyrac2查询对应的资源信息如下：

[grid@jyrac2 ~]$ crsctl stat res -t--------------------------------------------------------------------------------NAME TARGETSTATESERVER STATE_DETAILS --------------------------------------------------------------------------------Local Resources--------------------------------------------------------------------------------ora.DATA1.dg ONLINEONLINE jyrac2 ora.FRA1.dg ONLINEONLINE jyrac2 ora.LISTENER.lsnr ONLINEONLINE jyrac2 ora.OCR1.dg ONLINEONLINE jyrac2 ora.asm ONLINEONLINE jyrac2 Started ora.gsd OFFLINE OFFLINEjyrac2 ora.net1.network ONLINEONLINE jyrac2 ora.ons ONLINEONLINE jyrac2 ora.registry.acfs ONLINEONLINE jyrac2 --------------------------------------------------------------------------------Cluster Resources--------------------------------------------------------------------------------ora.LISTENER_SCAN1.lsnr1ONLINEONLINE jyrac2 ora.cvu1ONLINEONLINE jyrac2 ora.jyrac1.vip1ONLINEINTERMEDIATE jyrac2 FAILED OVER ora.jyrac2.vip1ONLINEONLINE jyrac2 ora.jyzhao.db1ONLINEOFFLINE Instance Shutdown 2ONLINEONLINE jyrac2 Openora.oc4j1ONLINEONLINE jyrac2 ora.scan1.vip1ONLINEONLINE jyrac2

2.节点宕机后，另一个节点的网络信息

查看在主机jyrac2网络信息：

[grid@jyrac2 ~]$ ifconfig -aeth2Link encap:EthernetHWaddr 08:00:27:1A:5A:7Ainet addr:192.168.56.152Bcast:192.168.56.255Mask:255.255.255.0inet6 addr: fe80::a00:27ff:fe1a:5a7a/64 Scope:LinkUP BROADCAST RUNNING MULTICASTMTU:1500Metric:1RX packets:3955 errors:0 dropped:0 overruns:0 frame:0TX packets:8277 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:1000 RX bytes:510869 （498.8 KiB）TX bytes:692985 （676.7 KiB）eth2:1Link encap:EthernetHWaddr 08:00:27:1A:5A:7Ainet addr:192.168.56.153Bcast:192.168.56.255Mask:255.255.255.0UP BROADCAST RUNNING MULTICASTMTU:1500Metric:1eth2:2Link encap:EthernetHWaddr 08:00:27:1A:5A:7Ainet addr:192.168.56.151Bcast:192.168.56.255Mask:255.255.255.0UP BROADCAST RUNNING MULTICASTMTU:1500Metric:1eth2:3Link encap:EthernetHWaddr 08:00:27:1A:5A:7Ainet addr:192.168.56.160Bcast:192.168.56.255Mask:255.255.255.0UP BROADCAST RUNNING MULTICASTMTU:1500Metric:1eth3Link encap:EthernetHWaddr 08:00:27:7C:CD:9Finet addr:10.10.10.12Bcast:10.10.10.255Mask:255.255.255.0inet6 addr: fe80::a00:27ff:fe7c:cd9f/64 Scope:LinkUP BROADCAST RUNNING MULTICASTMTU:1500Metric:1RX packets:116635 errors:0 dropped:0 overruns:0 frame:0TX packets:103705 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:1000 RX bytes:81979594 （78.1 MiB）TX bytes:63727783 （60.7 MiB）eth3:1Link encap:EthernetHWaddr 08:00:27:7C:CD:9Finet addr:169.254.198.12Bcast:169.254.255.255Mask:255.255.0.0UP BROADCAST RUNNING MULTICASTMTU:1500Metric:1loLink encap:Local Loopbackinet addr:127.0.0.1Mask:255.0.0.0inet6 addr: ::1/128 Scope:HostUP LOOPBACK RUNNINGMTU:16436Metric:1RX packets:145545 errors:0 dropped:0 overruns:0 frame:0TX packets:145545 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:0 RX bytes:130875345 （124.8 MiB）TX bytes:130875345 （124.8 MiB）

3.可ping通宕机节点VIP，但无对应监听

发现能ping通故障节点VIP，但并没有对应的监听程序。
ping可以通，如下：

[root@jyrac2 ~]# ping 192.168.56.151PING 192.168.56.151 （192.168.56.151） 56（84） bytes of data.64 bytes from 192.168.56.151: icmp_seq=1 ttl=64 time=0.023 ms64 bytes from 192.168.56.151: icmp_seq=2 ttl=64 time=0.036 ms64 bytes from 192.168.56.151: icmp_seq=3 ttl=64 time=0.051 ms64 bytes from 192.168.56.151: icmp_seq=4 ttl=64 time=0.069 ms^C--- 192.168.56.151 ping statistics ---4 packets transmitted, 4 received, 0% packet loss, time 3229msrtt min/avg/max/mdev = 0.023/0.044/0.069/0.019 ms

没有监听，通过此VIP自然连接不上，如下：

[root@jyrac2 ~]# sqlplus system/oracle@192.168.56.151/jyzhaoSQL*Plus: Release 11.2.0.4.0 Production on Thu Nov 3 16:58:31 2016Copyright （c） 1982, 2013, Oracle.All rights reserved.ERROR:ORA-12541: TNS:no listenerEnter user-name: #查看监听，确认的确只有scan ip和节点2的ip和vip被监听；节点1的vip的确是没有被监听。[root@jyrac2 ~]# ps -ef|grep tnsroot15 20 09:05 ？00:00:00 [netns]grid2845 10 09:07 ？00:00:00 /opt/app/11.2.0/grid/bin/tnslsnr LISTENER -inheritgrid6867 10 09:34 ？00:00:00 /opt/app/11.2.0/grid/bin/tnslsnr LISTENER_SCAN1 -inheritroot 13951 109530 17:17 pts/000:00:00 grep tns[root@jyrac2 ~]# su - grid[grid@jyrac2 ~]$ lsnrctl status LISTENERLSNRCTL for Linux: Version 11.2.0.4.0 - Production on 03-NOV-2016 17:18:09Copyright （c） 1991, 2013, Oracle.All rights reserved.Connecting to （DESCRIPTION=（ADDRESS=（PROTOCOL=IPC）（KEY=LISTENER）））STATUS of the LISTENER------------------------Alias LISTENERVersion TNSLSNR for Linux: Version 11.2.0.4.0 - ProductionStart Date03-NOV-2016 09:07:20Uptime0 days 8 hr. 10 min. 49 secTrace Level offSecurityON: Local OS AuthenticationSNMPOFFListener Parameter File /opt/app/11.2.0/grid/network/admin/listener.oraListener Log File /opt/app/grid/diag/tnslsnr/jyrac2/listener/alert/log.xmlListening Endpoints Summary...（DESCRIPTION=（ADDRESS=（PROTOCOL=ipc）（KEY=LISTENER）））（DESCRIPTION=（ADDRESS=（PROTOCOL=tcp）（HOST=192.168.56.152）（PORT=1521）））（DESCRIPTION=（ADDRESS=（PROTOCOL=tcp）（HOST=192.168.56.153）（PORT=1521）））Services Summary...Service "+ASM" has 1 instance（s）.Instance "+ASM2", status READY, has 1 handler（s） for this service...Service "jyzhao" has 1 instance（s）.Instance "jyzhao2", status READY, has 1 handler（s） for this service...Service "jyzhaoXDB" has 1 instance（s）.Instance "jyzhao2", status READY, has 1 handler（s） for this service...The command completed successfully[grid@jyrac2 ~]$ lsnrctl status LISTENER_SCAN1LSNRCTL for Linux: Version 11.2.0.4.0 - Production on 03-NOV-2016 17:18:18Copyright （c） 1991, 2013, Oracle.All rights reserved.Connecting to （DESCRIPTION=（ADDRESS=（PROTOCOL=IPC）（KEY=LISTENER_SCAN1）））STATUS of the LISTENER------------------------Alias LISTENER_SCAN1Version TNSLSNR for Linux: Version 11.2.0.4.0 - ProductionStart Date03-NOV-2016 09:34:20Uptime0 days 7 hr. 43 min. 58 secTrace Level offSecurityON: Local OS AuthenticationSNMPOFFListener Parameter File /opt/app/11.2.0/grid/network/admin/listener.oraListener Log File /opt/app/11.2.0/grid/log/diag/tnslsnr/jyrac2/listener_scan1/alert/log.xmlListening Endpoints Summary...（DESCRIPTION=（ADDRESS=（PROTOCOL=ipc）（KEY=LISTENER_SCAN1）））（DESCRIPTION=（ADDRESS=（PROTOCOL=tcp）（HOST=192.168.56.160）（PORT=1521）））Services Summary...Service "jyzhao" has 1 instance（s）.Instance "jyzhao2", status READY, has 1 handler（s） for this service...Service "jyzhaoXDB" has 1 instance（s）.Instance "jyzhao2", status READY, has 1 handler（s） for this service...The command completed successfully[grid@jyrac2 ~]$

4.知识点总结

回到本文开头提出的问题：
RAC 某节点不可用时，其对应VIP是否可用？是否可用于连接数据库？
答：RAC 某节点不可用时，其对应VIP可ping通。但由于没有监听，所以不可用于连接数据库。最后思考下，VIP既然failover漂移后可以ping通，但却没有对应的监听程序导致节点故障时不能再用此节点的vip连接数据库，那么VIP设置的意义何在呢？
从网络上搜索一些资料也可以得知：
VIP 是在出现故障的时候保证不用等待底层的TCP/IP 协议来诊断断开连接，而使用RAC级别来诊断，这样会很快。
简单举例子来说，就是节点1故障后，其VIP会漂移到节点2；但是由于节点2并没有对节点1这个VIP地址进行监听，这样客户端就能迅速知道节点1故障，从而切换到节点2；另外，需要注意的是，如果要实现failover，那么tnsnames.ora中要有相应的配置。关于RAC的tnsnames.ora配置具体可参见Oracle RAC客户端tnsnames.ora相关配置及测试更多Oracle相关信息见Oracle 专题页面 http://www.linuxidc.com/topicnews.aspx？tid=12本文永久更新链接地址