can be connected directly via SECURECRT or Telnet
Start listening command: Lsnrctl start
After successful boot: Sqlplus/nolog enter
Conn/as SYSDBA Enter
Startup return
SELECT * from User_tables; Enter
Results, OK start monitoring and service success
Attached error due to no service:
A workaround for ORA-01034 and ORA-27101
1 See if Oracle 's monitoring and Oracle's services are all started. To start Oracle snooping:
CMD in the command-line window, enter Lsnrctl start, and press ENTER to start monitoring.
2 to see what ORACLE's SID is called, such as when creating a database , the instance is called "abc", then manually set the Oralce sid,cmd Command window, set ORACLE_SID=ABC
3 re-enter Sqlplus/nolog, return
Re-enter Conn/as sysdba;
4 re-enter startup, enter. This step is to start the Oracle service. If startup is notified that it has been started, you can enter shutdown immediate first, and then enter startup after the shutdown is finished.
5 After a few seconds, and so on, the command can be connected. At this time, you can enter "select * from User_tables;" Test to see if there are any query results.
6 The causes of ORA-01034 and ORA-27101 are manifold: Oracle's current service is not available, shared memory realm does not exist, because Oracle does not boot or does not start properly, Shared memory is not assigned to the current instance. Therefore, start the database by setting the instance name and then using the operating system authentication method. In this way, the database starts normally, and the ORA-01034 and ORA-27101 are not reported as two boot exceptions.
-------------------------------------------------------------------------------------------
A ORA-27101 error was encountered on the test library today, and is returned as follows when connecting to DB via the client:
[Email protected] admin]$ sqlplussystem/[email protected]
Sql*plus:release 11.1.0.6.0-production on Tue 10 11:05:04 2010
Copyright (c) 1982, Oracle. All rights reserved.
ERROR:
Ora-01034:oracle Not available
Ora-27101:shared Memory realm does not exist
linux-x86_64 error:2: No such file or directory
Process id:0
Session id:0 Serial number:0
For the first impression of this issue, you may feel that there is not enough memory space to create a shared memory segment
1. First check the kernel parameter settings and the Alert.log file
Fs.file-max = 6553600
Kernel.shmall = 2097152
Kernel.shmmax = 2147483648
Kernel.shmmni = 4096
Kernel.sem = 250 32000 100 128
Net.ipv4.ip_local_port_range = 9000 65500
Net.core.rmem_default = 4194304
Net.core.rmem_max = 4194304
Net.core.wmem_default = 262144
Net.core.wmem_max = 1048576
No problem after viewing, the host has enough memory and the database is already in the boot state:
Sql> select Open_mode from V$database;
Open_mode
----------
READ WRITE
2. After the error is found, continue to enter the user name and password can login
Enter User-name:system
Enter Password:
Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.6.0-64bit Production
With the partitioning, OLAP, Data Mining and Real application testing options
Sql>
3. View Sqlnet.log Logs
[Email protected] log]$ pwd
/u01/app/product/11.1.0/db_1/network/log
[email protected] log]$ cat Sqlnet.log
Directory does not exist for Read/write [/u01/app/product/11.1.0/db_1/log] [/u01/app/product/11.1.0/db_1/log/diag/ Clients]
***********************************************************************
Fatal NI Connect error 12541, connecting to:
(Description= (address= (protocol=tcp) (host=10.201.1.134) (port=1521)) (Connect_data= (Service_name=oracle8) (CID= ( [email protected]) (Host=localhost) (user=oracle))))
VERSION Information:
TNS for Linux:version 11.1.0.6.0-production
TCP/IP NT Protocol Adapter for Linux:version 11.1.0.6.0-production
time:05-aug-2010 18:30:51
Tracing not turned on.
Tns error struct:
NS Main ERR code:12541
Tns-12541:tns:no Listener
NS Secondary Err code:12560
NT Main ERR code:511
Tns-00511:no Listener
NT Secondary Err code:111
NT OS Err code:0
***********************************************************************
Tip: Listener not found ...
4. Check that the listener is configured correctly
[Email protected] alert]$ Cat/u01/app/product/11.1.0/db_1/network/admin/listener.ora
# Listener.ora Network Configuration File:/u01/app/product/11.1.0/db_1//network/admin/listener.ora
# Generated by Oracle configuration tools.
Sid_list_listener =
(Sid_list =
(Sid_desc =
(Oracle_home =/u01/app/product/11.1.0/db_1)
(Sid_name = siebtest)
)
)
LISTENER =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP) (HOST = 10.201.1.134) (PORT = 1521))
)
[Email protected] ~]$ tnsping test
Used parameter files:
/u01/app/product/11.1.0/db_1/network/admin/sqlnet.ora
Used TNSNames Adapter to resolve the alias
Attempting to contact (DESCRIPTION = (Address_list = (ADDRESS = (PROTOCOL = TCP) (HOST = 10.201.1.134) (PORT = 1521)) (CONN Ect_data = (service_name = siebtest)))
OK (0 msec)
Listener Configuration No problem ...
5. Because the instance is already in the boot state, this time consider the issue of instance registration
Sql> Show Parameter Local_listener
NAME Typevalue
------------------------------------ ----------- ------------------------------
Local_listener string
Found Local_listener no value .....
6. Setting the Local_listener parameter
Sql> alter system set local_listener= ' (ADDRESS = (protocol=tcp) (host=10.201.1.134) (port=1521) (sid=siebtest)) ';
System altered.
Sql> alter system register;
System altered.
7. Successful re-landing
[Email protected] alert]$ sqlplussystem/[email protected]
Sql*plus:release 11.1.0.6.0-production on Tue 10 12:51:11 2010
Copyright (c) 1982, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.6.0-64bit Production
With the partitioning, OLAP, Data Mining and Real application testing options
Sql>
Summarize:
If Local_listener is lost, the automatic instance registration fails, and the DB instance does not recognize listener when the listener connection
DB instance, due to listener not registered, resulting in ora-27101:shared memory realm does not exist.
Linux starts Oracle monitoring and service