安装Oracle 11.2.0.4 的RAC，在Grid 安装时报错：
[INS-41112]Specified network interface doesnt maintain connectivity across cluster nodes
首先尝试在节点间ping 各个IP 地址没有问题。
因为使用安装程序做的SSH 验证，所以尝试测试ssh远程连接是否还需要确认：
[grid@vdb1 ~]$ ssh vdb1 date # 验证vdb1 ssh Thu Aug 7 15:20:44 CST 2014 [grid@vdb1 ~]$ ssh vdb2 date # 验证vdb2 ssh Thu Aug 7 15:20:49 CST 2014 [grid@vdb1 ~]$ ssh vdb1-priv date # 验证 vdb1-priv ssh The authenticity of host ‘vdb1-priv (172.168.1.18)‘ can‘t be established. RSA key fingerprint is 92:66:57:37:7b:fe:b0:05:5a:9b:ec:b5:3f:d1:07:8f. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added ‘vdb1-priv,172.168.1.18‘ (RSA) to the list of known hosts. Thu Aug 7 15:21:05 CST 2014 [grid@vdb1 ~]$ ssh vdb2-priv date # 验证 vdb2-priv ssh The authenticity of host ‘vdb2-priv (172.168.1.19)‘ can‘t be established. RSA key fingerprint is 92:66:57:37:7b:fe:b0:05:5a:9b:ec:b5:3f:d1:07:8f. Are you sure you want to continue connecting (yes/no)? yes Warning: Permanently added ‘vdb2-priv,172.168.1.19‘ (RSA) to the list of known hosts. Thu Aug 7 15:21:18 CST 2014
发现使用vdb1-priv和vdb2-priv时需要确认，在2个节点间互相确认后，该步骤任然未通过验证。
检查发现是没有关闭防火墙 ，关闭两个节点的防火墙后，该问题解决。
原文：http://www.cnblogs.com/mawanglin2008/p/3897284.html