该文章借鉴了https://www.cnblogs.com/nichoc/p/6417505.html的示例
提示该异常说明了两个前提，第一是Oracle数据库是开启状态，第二是监听程序处于开启状态
解决步骤：
切换到Oracle用户
查看监听状态
lsnrctl status
READY说明为动态监听，UNKNOWN则为静态监听（该判断不够准确，具体要到/network/admin/目录下的listener.ora里查看，如果不存在该配置文件，或者未配置SID_LIST_[监听名]（ps：SID_LIST_LISTENER）则为动态监听）
（1） 当为READY（动态监听）
Oracle会监听所有启用实例，启用动态监听却提示(监听程序当前无法识别连接描述符中请求服务)异常说明该实例被关闭了，所以我们要做的就是开启我们需要访问的实例即可
切换实例用户：
export ORACLE_SID=tbzg（实例名）（不知道实例名去$ORACLE_HOME/dbs目录去查看）
连接服务：
启动服务：
Startup退出服务
exit查看当前有多少个已经启动的实例：
ps -ef|grep smon
发现tbzg已经启动
查看监听状态
问题解决
修改listener.ora和tnsnames.ora，重启oracle，监听，并注册
以
为例
<1>修改listener.ora
/network/admin/目录下，查看自己Oracle的安装目录
原：
改：
# listener.ora Network Configuration File: /data/oracle/product/11.2.0/db_1/network/admin/listener.ora# Generated by Oracle configuration tools.#LIST_LISTENER 为监听名字SID_LIST_LISTENER =(SID_LIST =(SID_DESC =(GLOBAL_DBNAME = orcl) ##listener.ora中GLOBAL_DBNAME的值 == tnsnames.ora中的SERVICE_NAME(ORACLE_HOME = /data/oracle/product/11.2.0/db_1)(SID_NAME = orcl) ##可通过env | grep ORACLE查看SID_NAME和$ORACLE_HOME的值，先切换到对应实例export ORACLE_SID=实例名))LISTENER = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.78.130)(PORT = 1521)))ADR_BASE_LISTENER = /data/oracle[监听名]和SID_LIST_[监听名]配置是成对出现
配置listener.ora中GLOBAL_DBNAME的值等于tnsnames.ora中的SERVICE_NAME
<2>修改tnsnames.ora
/network/admin/目录下，查看自己Oracle的安装目录
原：
改：
# tnsnames.ora Network Configuration File: /data/oracle/product/11.2.0/db_1/network/admin/tnsnames.ora# Generated by Oracle configuration tools.orcl = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.78.130)(PORT = 1521)) ) (CONNECT_DATA = (SID = orcl) ) )<3>重启监听更新注册
lsnrctl stop #先关闭监听服务lsnrctl start #开启监听服务console：
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 19-FEB-2017 21:24:22Copyright (c) 1991, 2009, Oracle. All rights reserved.Starting /data/oracle/product/11.2.0/db_1/自由的灯泡/tnslsnr: please wait...TNSLSNR for Linux: Version 11.2.0.1.0 - ProductionSystem parameter file is /data/oracle/product/11.2.0/db_1/network/admin/listener.oraLog messages written to /data/oracle/diag/tnslsnr/localhost/listener/alert/log.xmlListening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.78.130)(PORT=1521)))Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.78.130)(PORT=1521)))STATUS of the LISTENER------------------------Alias LISTENERVersion TNSLSNR for Linux: Version 11.2.0.1.0 - ProductionStart Date 19-FEB-2017 21:24:22Uptime 0 days 0 hr. 0 min. 0 secTrace Level offSecurity ON: Local OS AuthenticationSNMP OFFListener Parameter File /data/oracle/product/11.2.0/db_1/network/admin/listener.oraListener Log File /data/oracle/diag/tnslsnr/localhost/listener/alert/log.xmlListening Endpoints Summary... (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.78.130)(PORT=1521)))Services Summary...Service "orcl" has 1 instance(s). Instance "orcl", status UNKNOWN, has 1 handler(s) for this service...The command completed successfully[oracle@localhost ~]$注意看启动端口时候生效
sqlplus / as sysdba #登入shutdown immediate #立即关闭数据库服务startup #开启数据库服务alter system register; #注册 quit #登出lsnrctl status #查看监听状态console：
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 19-FEB-2017 21:37:20Copyright (c) 1991, 2009, Oracle. All rights reserved.Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.78.130)(PORT=1521)))STATUS of the LISTENER------------------------Alias LISTENERVersion TNSLSNR for Linux: Version 11.2.0.1.0 - ProductionStart Date 19-FEB-2017 21:24:22Uptime 0 days 0 hr. 12 min. 57 secTrace Level offSecurity ON: Local OS AuthenticationSNMP OFFListener Parameter File /data/oracle/product/11.2.0/db_1/network/admin/listener.oraListener Log File /data/oracle/diag/tnslsnr/localhost/listener/alert/log.xmlListening Endpoints Summary... (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.78.130)(PORT=1521)))Services Summary...Service "orcl" has 1 instance(s). Instance "orcl", status UNKNOWN, has 1 handler(s) for this service...The command completed successfully[oracle@localhost ~]$再次用plsql访问成功