Oracle cannot start tnslistener service cannot start

1 Cause analysis

There are two situations , situation A： It's the end of the installation oracle after , For the first time , appear tnslistener The service failed to start ; situation B：Oracle It can always be used , But suddenly one day , Because loading and unloading other software or computer operation , That led to tnslistener The service failed to start .

situation A, Mostly for tnsnames.ora File configuration error , Need to add a paragraph , Detailed method reference ：

tnsnames.ora The contents are as follows

ORCL = 
   (DESCRIPTION = 
     (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.105)(PORT = 1521)) 
     (CONNECT_DATA = 
       (SERVER = DEDICATED) 
       (SERVICE_NAME = orcl.168.0.105) 
     ) 
   ) 
listener.ora The contents are as follows  
LISTENER = 
   (DESCRIPTION_LIST = 
     (DESCRIPTION = 
       (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521)) 
     ) 
     (DESCRIPTION = 
  
       (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.105)(PORT = 1521)) 
     ) 
   ) 

situation B, Mostly because the configuration of environment variables has changed , At this time, you need to recheck the environment variables .

Normal environment variables only need to set these two , stay path in

No need to set ORACLE_HOME and TNS_ADMIN, Set up ORACLE_HOME and TNS_ADMIN It can lead to ORA-12541 Error of .

1、ORACLE_HOME A variable's value E:\Oracle\product\11.2.0\dbhome_1
explain ： The variable value here is installed by yourself Oracle Database installation path , In the path you will find project Then find... In turn dbhome_1, Then copy the path to the environment variable value .
2、TNS_ADMIN Variable name TNS_ADMIN A variable's value E:\Oracle\product\11.2.0\dbhome_1\NETWORK\ADMIN
explain ： Careful friends may see TNS_ADMIN The variable value of is in ORACLE_HOME Another two-level file is found under the variable value path of .

• Other situations , You can refer to the collation of netizens ：https://blog.csdn.net/qiruiduni/article/details/44016325

The origin of writing this article

2020 year 10 month 6 Japan , One day of national day , I continue to work on the station , Found that the national day a few days because of loading and unloading ARCGIS、Python Environment and other related software , Lead to Oracle Can't start . At first, I thought it was ok , Just look for the reason , But after half an hour of searching , It is not found that the reasons described by netizens , I will rethink what I did to the computer before . So I thought of the problem that may be caused by environmental variables . therefore , I'm right again Oracle Relevant environment variables of have been checked , Find out Oracle_home There are too many configurations （ As for why not , Maybe it's because my hands are too cheap ）.