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ORA-12170:TNS:连接超时解决一例

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Jun 07, 2016 pm 05:24 PM

前几天在机房连接数据库服务器时，报了rdquo;ORA-12170:TNS:连接超时rdquo;。这个错误费了我两天的时间才把问题解决掉，现在总

前几天在机房连接数据库服务器时，报了”ORA-12170:TNS:连接超时”。这个错误费了我两天的时间才把问题解决掉，现在总结下，希望大家少走些弯路

从错误的信息上看，是肯定是本地的客户端和服务器没有连接好，两个机器的Oracle直接不能通信。这个问题就多了，现总结一下：

一tns的配置文件不对

这个问题是最基本的，这是连接的基础。这个我建议直接从服务器上拷贝，就不会出错了。我见过的就是因为服务器名后有空格，导致了服务器无法解析。

二服务器的防火墙开了

防火墙会组织tns直接的连接，验证可以把服务器的防火墙关了试试看。

三路由的配置问题

这是我今天想说的，也是花了我两天的时间弄明白的地方。对于那些既要用外网上网收发邮件，又要用内网连接服务器的用户，这点尤其重要。

我在机房时，用无线连接外网做上网用，用有线连接内网做连接数据库用。正常情况下，是不能同时实现外网和内网的同时访问的，必须先把路由表的信息设置下，使外网和内网的网关不在同一个子网掩码上。可以在控制台下用 route print 查看本地的路由信息。

大家可能没有看没明白，我举例说明。下面这张图是我连不上服务器时的路由信息，重点是前面的两行，可以明显的看到我的外网的网关（192.168.1.1）和内网的网关（132.77.124.129）在同一网络掩码（0.0.0.0）内，这样路由就无法解析了。

ORA-12170:TNS:连接超时解决一例

这时可以把外网的无线网络断掉，这样内网就可以连接上了。我正是看到了这点，才明白是网络的原因，不是tns的原因。接下来，，我就该看怎样实现内网和外网的同时访问了。

我用了以下的命令：

route delete 0.0.0.0

route add 0.0.0.0 mask 0.0.0.0 192.168.1.1

route add 132.77.0.0 mask 255.255.0.0 132.77.124.129

route add 132.78.0.0 mask 255.255.0.0 132.77.124.129

route add 10.193.0.0 mask 255.255.0.0 132.77.124.129

可以逐条的在控制台下输入，也可以做成bat文件的形式直接的手工执行。运行完后，我的路由信息如下图所示

ORA-12170:TNS:连接超时解决一例

同样可以明显的看到我的外网的网关（192.168.1.1）和内网的网关（132.77.124.129）不在同一个网络掩码内了，这样路由就可以解析了。

总结一下，出现这个问题不要慌，要一步步的去找问题的原因。

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