Oracle DB启动

Oracle DB启动，一共有三个阶段，分别为nomount，mount，open。

 

 

1、启动Oracle DB 实例：NOMOUNT

 

 

在创建数据库期间、重新创建控制文件期间，或执行某些备份和恢复方案期间，通常只在NOMOUNT模式下启动实例。

 

启动实例过程包括执行以下任务：

• 按以下顺序搜索$ORACLE_HOME/dbs中具有特定名称的文件：

1. 搜索spfile<SID>.ora。

2. 如果未找到spfile<SID>.ora，则搜索spfile.ora。

3. 如果未找到spfile.ora，则搜索init<SID>.ora。

这是包含实例初始化参数的文件。使用STARTUP指定PFILE参数可覆盖默认行为。

• 分配SGA

• 启动后台进程

• 打开alert_<SID>.log文件和跟踪文件

注：SID是用于标识实例的系统ID（例如ORCL）。

 

命令：

sys@TEST0924> startup nomount;

 

ORACLE instance started.

 

Total System Global Area 2505338880 bytes

Fixed Size 2230952 bytes

Variable Size 620758360 bytes

Database Buffers 1862270976 bytes

Redo Buffers 20078592 bytes

 

alert_test0924.log日志查看：

Wed Oct 02 16:33:04 2013

Adjusting the default value of parameter parallel_max_servers

from 320 to 135 due to the value of parameter processes (150)

Starting ORACLE instance (normal)

****************** Large Pages Information *****************

Total Shared Global Region in Large Pages = 0 KB (0%)

Large Pages used by this instance: 0 (0 KB)

Large Pages unused system wide = 0 (0 KB) (alloc incr 16 MB)

Large Pages configured system wide = 0 (0 KB)

Large Page size = 2048 KB

RECOMMENDATION:

Total Shared Global Region size is 2402 MB. For optimal performance,

prior to the next instance restart increase the number

of unused Large Pages by atleast 1201 2048 KB Large Pages (2402 MB)

system wide to get 100% of the Shared

Global Region allocated with Large pages

***********************************************************

LICENSE_MAX_SESSION = 0

LICENSE_SESSIONS_WARNING = 0

Picked latch-free SCN scheme 3

Using LOG_ARCHIVE_DEST_1 parameter default value as USE_DB_RECOVERY_FILE_DEST

Autotune of undo retention is turned on.

IMODE=BR

ILAT =27

LICENSE_MAX_USERS = 0

SYS auditing is disabled

Starting up:

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options.

ORACLE_HOME = /u01/app/oracle/product/11.2.0/dbhome_1

System name: Linux

Node name: rtest.localdomain

Release: 2.6.18-308.el5

Version: #1 SMP Fri Jan 27 17:17:51 EST 2012

Machine: x86_64

VM name: VMWare Version: 6

Using parameter settings in server-side spfile /u01/app/oracle/product/11.2.0/dbhome_1/dbs/spfiletest0924.ora

System parameters with non-default values:

processes = 150

shared_pool_size = 496M

sga_target = 2400M

control_files = "/u01/app/oracle/oradata/test0924/control01.ctl"

control_files = "/u01/app/oracle/fast_recovery_area/test0924/control02.ctl"

db_block_size = 8192

db_keep_cache_size = 48M

compatible = "11.2.0.0.0"

db_recovery_file_dest = "/u01/app/oracle/fast_recovery_area"

db_recovery_file_dest_size= 4122M

undo_tablespace = "UNDOTBS2"

remote_login_passwordfile= "EXCLUSIVE"

db_domain = ""

dispatchers = "(PROTOCOL=TCP) (SERVICE=test0924XDB)"

audit_file_dest = "/u01/app/oracle/admin/test0924/adump"

audit_trail = "DB"

db_name = "test0924"

open_cursors = 300

pga_aggregate_target = 798M

sec_max_failed_login_attempts= 2

diagnostic_dest = "/u01/app/oracle"

Wed Oct 02 16:33:04 2013

PMON started with pid=2, OS id=14904

Wed Oct 02 16:33:04 2013

PSP0 started with pid=3, OS id=14906

Wed Oct 02 16:33:05 2013

VKTM started with pid=4, OS id=14908 at elevated priority

VKTM running at (1)millisec precision with DBRM quantum (100)ms

Wed Oct 02 16:33:05 2013

GEN0 started with pid=5, OS id=14912

Wed Oct 02 16:33:05 2013

DIAG started with pid=6, OS id=14914

Wed Oct 02 16:33:05 2013

DBRM started with pid=7, OS id=14916

Wed Oct 02 16:33:05 2013

DIA0 started with pid=8, OS id=14918

Wed Oct 02 16:33:05 2013

MMAN started with pid=9, OS id=14920

Wed Oct 02 16:33:06 2013

DBW0 started with pid=10, OS id=14922

Wed Oct 02 16:33:06 2013

LGWR started with pid=11, OS id=14924

Wed Oct 02 16:33:06 2013

CKPT started with pid=12, OS id=14926

Wed Oct 02 16:33:06 2013

SMON started with pid=13, OS id=14928

Wed Oct 02 16:33:06 2013

RECO started with pid=14, OS id=14930

Wed Oct 02 16:33:06 2013

MMON started with pid=15, OS id=14932

Wed Oct 02 16:33:06 2013

MMNL started with pid=16, OS id=14934

starting up 1 dispatcher(s) for network address '(ADDRESS=(PARTIAL=YES)(PROTOCOL=TCP))'...

starting up 1 shared server(s) ...

ORACLE_BASE from environment = /u01/app/oracle

 

 

2、启动Oracle DB 实例：MOUNT

 

 

 

数据库装载过程包括执行以下任务：

• 将数据库与以前启动的实例关联

• 定位并打开参数文件中指定的控制文件

• 通过读取控制文件来获取数据文件和联机重做日志文件的名称和状态（但是，此时不会执行检查来验证是否存在数据文件和联机重做日志文件）。

 

要执行特定的维护操作，则启动实例，然后装载数据库，但不打开该数据库。

例如，在执行以下任务期间必须装载数据库，但不得打开数据库：

• 重命名数据文件（打开数据库时可重命名脱机表空间的数据文件）。

• 启用和禁用联机重做日志文件归档选项

• 执行完整的数据库恢复

 

注：即使发出了OPEN请求，数据库仍可能处于MOUNT模式下。这是因为可能需要以某种方式恢复数据库。如果在MOUNT状态下执行恢复，将打开重做日志进行读取，并打开数据文件读取需要恢复的块，以及在恢复期间根据需要写入块。

 

 

命令：

ys@TEST0924> alter database mount;

 

Database altered.

 

alert_test0924.log日志查看：

ed Oct 02 16:34:21 2013

alter database mount

Wed Oct 02 16:34:25 2013

Successful mount of redo thread 1, with mount id 2721621517

Database mounted in Exclusive Mode

Lost write protection disabled

Completed: alter database mount

 

 

3、启动Oracle DB 实例：OPEN

 

 

 

数据库操作正常意味着实例已启动、数据库已装载且已打开。在数据库操作正常时，任何有效用户都可连接到数据库，而且可执行典型数据访问操作。

打开数据库过程包括执行以下任务：

• 打开数据文件

• 打开联机重做日志文件

如果尝试打开数据库时任一数据文件或联机重做日志文件不存在，则Oracle 服务器返回错误。

 

在最后这个阶段，Oracle 服务器会验证是否可以打开所有数据文件和联机重做日志文件，还会检查数据库的一致性。如有必要，系统监视器(SMON) 后台进程将启动实例恢复。可以在受限模式下启动数据库实例，以便只让有管理权限的用户使用该实例。要在受限模式下启动实例，可在“Advanced Startup Options（高级启动选项）”页上选择“Restrict access to database（限制对数据库的访问）”选项。

或者在启动Open模式时，添加restrict关键字：startup restrict，

设置或取消受限状态：alter system enabledisable restricted session;

 

命令：

sys@TEST0924> alter database open;

 

Database altered.

 

 

alert_test0924.log日志查看：

 

 

Wed Oct 02 16:35:45 2013

alter database open

Wed Oct 02 16:35:45 2013

LGWR: STARTING ARCH PROCESSES

Wed Oct 02 16:35:45 2013

ARC0 started with pid=20, OS id=15283

ARC0: Archival started

LGWR: STARTING ARCH PROCESSES COMPLETE

ARC0: STARTING ARCH PROCESSES

Wed Oct 02 16:35:46 2013

ARC1 started with pid=21, OS id=15296

Wed Oct 02 16:35:46 2013

ARC2 started with pid=22, OS id=15298

Wed Oct 02 16:35:46 2013

ARC3 started with pid=23, OS id=15300

ARC1: Archival started

ARC2: Archival started

ARC2: Becoming the 'no FAL' ARCH

ARC2: Becoming the 'no SRL' ARCH

ARC1: Becoming the heartbeat ARCH

Thread 1 opened at log sequence 55

Current log# 1 seq# 55 mem# 0: /u01/app/oracle/oradata/test0924/redo01.log

Successful open of redo thread 1

MTTR advisory is disabled because FAST_START_MTTR_TARGET is not set

Wed Oct 02 16:35:46 2013

SMON: enabling cache recovery

[14939] Successfully onlined Undo Tablespace 5.

Undo initialization finished serial:0 start:627239824 end:627239864 diff:40 (0 seconds)

Verifying file header compatibility for 11g tablespace encryption..

Verifying 11g file header compatibility for tablespace encryption completed

SMON: enabling tx recovery

Database Characterset is AL32UTF8

No Resource Manager plan active

Starting background process FBDA

Wed Oct 02 16:35:47 2013

FBDA started with pid=24, OS id=15302

replication_dependency_tracking turned off (no async multimaster replication found)

Starting background process QMNC

Wed Oct 02 16:35:47 2013

QMNC started with pid=25, OS id=15304

Completed: alter database open

Wed Oct 02 16:35:47 2013

db_recovery_file_dest_size of 4122 MB is 48.29% used. This is a

user-specified limit on the amount of space that will be used by this

database for recovery-related files, and does not reflect the amount of

space available in the underlying filesystem or ASM diskgroup.

Wed Oct 02 16:35:47 2013

Starting background process CJQ0

Wed Oct 02 16:35:47 2013

CJQ0 started with pid=26, OS id=15318

ARC3: Archival started

ARC0: STARTING ARCH PROCESSES COMPLETE

 

4、启动选项：示例

 

此幻灯片显示用于启动数据库的SQL*Plus 语法。

1.startup：启动实例，将数据库文件与该实例关联，然后装载并打开数据库。

2alter database nomount：启动实例，但不装载数据库。

3.alter database mount：装载处于NOMOUNT状态的数据库。

4alter database open ：打开处于MOUNT状态的数据库。