./runcluvfy.sh stage -pre crsinst -n db1,db2 -verbose grid执行检查，发现存在组播无法通讯的情况，日志如下：
Checking subnet "192.168.0.0" for multicast communication with multicast group "230.0.1.0"...PRVG-11134 : Interface "192.168.0.14" on node "db2" is not able to communicate with interface "192.168.0.13" on node "db1"PRVG-11134 : Interface "192.168.0.13" on node "db1" is not able to communicate with interface "192.168.0.14" on node "db2"Checking subnet "192.168.0.0" for multicast communication with multicast group "224.0.0.251"...PRVG-11134 : Interface "192.168.0.14" on node "db2" is not able to communicate with interface "192.168.0.13" on node "db1"PRVG-11134 : Interface "192.168.0.13" on node "db1" is not able to communicate with interface "192.168.0.14" on node "db2"
oracle提供了一个测试的脚本工具mcasttest.pl
和华为云平台运维人员沟通后发现私有网卡的安全组配置为现在点对点ip的方式。所以导致组播地址无法通讯，修改安全组策略为不限制后再次进行测试组播可以正常通讯。
同时分享一个组播的测试工具参考mos文档《Grid Infrastructure Startup During Patching, Install or Upgrade May Fail Due to Multicasting Requirement (Doc ID 1212703.1) 》
如何使用mcasttest，前提节点间需要配置免密登陆：
信任关系配置如下grid免密登录/u01/soft/grid/sshsetup/sshUserSetup.sh -user grid -hosts "db1 db2" -noPromptPasshrase -confirm -advancedoracle免密等/u01/soft/database/sshsetup/sshUserSetup.sh -user oracle -hosts "db1 db2" -noPromptPasshrase -confirm -advanced
mcasttest测试：# gunzip mcasttest.tgz # tar xvf mcasttest.tar # perl mcasttest.pl -n <node1>,<node2>,<node_n...> -i <interface1>,<interface2><interface_n...>The example below tests multicast for a two node cluster (<node1> and <node2>), in which two network interfaces (eth1 and eth2) are to be used for the private interconnect:-n 节点名称-i 网卡名称
测试案例：测试私有网络的组播通讯情况/u01/soft/mcasttest> perl mcasttest.pl -n db1,db2 -i eth1########### Setup for node db1 ##########Checking node access 'db1'Checking node login 'db1'Checking/Creating Directory /tmp/mcasttest for binary on node 'db1'Distributing mcast2 binary to node 'db1'########### Setup for node db2 ##########Checking node access 'db2'Checking node login 'db2'Checking/Creating Directory /tmp/mcasttest for binary on node 'db2'Distributing mcast2 binary to node 'db2'########### testing Multicast on all nodes ##########Test for Multicast address 230.0.1.0Dec 11 10:31:06 | Multicast Succeeded for eth1 using address 230.0.1.0:42000Test for Multicast address 224.0.0.251Dec 11 10:31:07 | Multicast Succeeded for eth1 using address 224.0.0.251:42001grid@db1:/u01/soft/mcasttest>
Note: Multicast based communication only needs to be successful on either the 230.0.1.0 address or the 224.0.0.251 address. A successful multicast communication on both addresses is not required. 另外通讯在230和224任意网络上面都可以，不需要全部能通。