CODEWITHSUNDEEP
expressinstallationconnectionubuntu-18.04oracle18c
FreezeFrame
FreezeFrame

Reputation: 65

Installation of Oracle Express Ediion 18c on Ubuntu 18.04 Server - Connection problem

Installation
DB Version: Oracle 18c XE
on Ubuntu 18.04 Server running inside Virtual Machine Manager

Problem
After Installation of Oracle XE 18c I log on as user oracle and start the listener 

lsnrctl start

When I try to connect there are the following problems:

A. Using: 

sqlplus / as sysdba

=> 

ERROR:
ORA-12547: TNS:lost contact

B. Using:

sqlplus oracle@ubu-srv as sysdba

=> 

ORA-12514: TNS:listener does not currently know of service requested in connect descriptor

Check Listener:

lsnrctl status

=> 

LSNRCTL for Linux: Version 18.0.0.0.0 - Production on 28-MAR-2020 22:05:40  
Copyright (c) 1991, 2018, Oracle.  All rights reserved.  
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=ubu-srv)(PORT=1521)))

STATUS of the LISTENER

Alias                     LISTENER  
Version                   TNSLSNR for Linux: Version 18.0.0.0.0 - Production  
Start Date                28-MAR-2020 21:28:33  
Uptime                    0 days 0 hr. 37 min. 6 sec  
Trace Level               off  
Security                  ON: Local OS Authentication  
SNMP                      OFF  
Default Service           XE  
Listener Parameter File   /opt/oracle/product/18c/dbhomeXE/network/admin/listener.ora  
Listener Log File         /opt/oracle/diag/tnslsnr/ubu-srv/listener/alert/log.xml  
Listening Endpoints Summary...  
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=ubu-srv)(PORT=1521)))  
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))  
The listener supports no services  
The command completed successfully

Content of listener.ora: 

  # listener.ora Network Configuration File: /opt/oracle/product/18c/dbhomeXE/network/admin/listener.ora  
  # Generated by Oracle configuration tools.  

DEFAULT_SERVICE_LISTENER = XE  

LISTENER =  
  (DESCRIPTION_LIST =  
    (DESCRIPTION =  
      (ADDRESS = (PROTOCOL = TCP)(HOST = ubu-srv)(PORT = 1521))  
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))  
    )  
  )

Content of tnsnames.ora: 

  # tnsnames.ora Network Configuration File: /opt/oracle/product/18c/dbhomeXE/network/admin/tnsnames.ora  
  # Generated by Oracle configuration tools.  

LISTENER_XE =  
  (ADDRESS = (PROTOCOL = TCP)(HOST = ubu-srv)(PORT = 1521))

Upvotes: 2

Views: 1401

Answers (1)

pmdba
pmdba

Reputation: 7043

It doesn't appear that the database is running, or if it is that it has registered with the network listener. If the database was running, you should see several services listed when you run "lsnrctl status", like this:

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=dbhost.example.com)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 18.0.0.0.0 - Production
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Default Service           XE
Listener Parameter File   /opt/oracle/product/18c/dbhomeXE/network/admin/listener.ora
Listener Log File         /opt/oracle/diag/tnslsnr/dbhost/listener/alert/log.xml
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=dbhost.example.com)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=dbhost.example.com)(PORT=5500))(Security=(my_wallet_directory=/opt/oracle/admin/XE/xdb_wallet))(Presentation=HTTP)(Session=RAW))
Services Summary...
Service "77f81bd10c818208e053410cc40aef5a" has 1 instance(s).
  Instance "XE", status READY, has 1 handler(s) for this service...
Service "XE" has 1 instance(s).
  Instance "XE", status READY, has 1 handler(s) for this service...
Service "XEXDB" has 1 instance(s).
  Instance "XE", status READY, has 1 handler(s) for this service...
Service "xepdb1" has 1 instance(s).
  Instance "XE", status READY, has 1 handler(s) for this service...
The command completed successfully

You shouldn't need the listener running at all for your Option A, connecting from the same host, but you will need to set the ORACLE_SID environment variable to match the SID of the database (Container or Pluggable DB) that you want to connect to. To connect to the container DB, as to manually start all database services, you would do this:

export ORACLE_SID=XE
sqlplus / as sysdba

For option B, connecting over the network, your connect string also appears malformed; it should usually include a service name (minimum) in addition to the hostname. See here for examples: https://docs.oracle.com/en/database/oracle/oracle-database/18/sqpug/starting-SQL-Plus.html#GUID-A33231E7-9180-4544-A055-411209FD0363

sqlplus username@[//]host[:port][/service_name]
sqlplus pdb_admin@ubu-srv:1521/xepdb1

That said, Oracle isn't certified with Ubuntu Linux, so results are not guaranteed. You should be running this on CentOS, Red Hat, or Oracle Linux. The full list of supported Linux versions is here: https://docs.oracle.com/en/database/oracle/oracle-database/18/ladbi/operating-system-checklist-for-oracle-database-installation-on-linux.html#GUID-E5C0A90E-7750-45D9-A8BC-C7319ED934F0

Upvotes: 2

Related Questions