oracle MTS模式下防火墙如何开通
最近在搭建一台测试环境时,发现开通监听1521端口的防火墙后,远程 连接还是无法连接,只有允许ip不限制端口时就能正常连接到数据库。 原因如下: 首先这台数据库是MTS,也就是共享模式: SQL show parameter shared_servers;NAME TYPE VALUE----------------
最近在搭建一台测试环境时,发现开通监听1521端口的防火墙后,远程 连接还是无法连接,只有允许ip不限制端口时就能正常连接到数据库。
原因如下:
首先这台数据库是MTS,也就是共享模式:
SQL> show parameter shared_servers; NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ max_shared_servers integer shared_servers integer 1
共享模式的连接方式是客户端连接监听如1521后,会redirect到dispatcher,而dispatcher的端口是随机的。如果你只开通了1521,那是连接不了数据库的,你会发现telnet ip 1521通,但就是连接不上数据库。
在这种情况 下你可以用如下方法解决:
可以在客户端进行Dedicated模式连接,在tnsnames.ora中增加SERVER=DEDICATED配置:
test = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.97.1)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = test) ) )
然后固定dispatcher的端口
# vi initSID.ora *.dispatchers="(address=(protocol=tcp)(port=49316))(dispatchers=3)"
重启实例
可以这样查看dispatcher的端口,然后再开通防火墙:
SQL> select name,network from v$dispatcher; NAME ---- NETWORK -------------------------------------------------------------------------------- D000 (ADDRESS=(PROTOCOL=tcp)(HOST=auto_oracle.dmc.com)(PORT=49316))
配置防火墙允许访问49316端口。
这个时候需要开通两个端口,一个是1521和49316。
原文地址:oracle MTS模式下防火墙如何开通, 感谢原作者分享。

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