Oracle DBA面对全新工作环境应该了解什么
在这里 , 不谈那些大的方面 , 比如了解整个 IT 环境整体情况 , 假设你已经知道了这些 , 接下来需要面对的就是这些一个个活生生的 database 了 . 这里总结了一些一般的思路来面对一个全先的 database, 从而快速了解你面对的环境概要。 这也不是教科书 , 只是
在这里,不谈那些大的方面,比如了解整个IT环境整体情况,假设你已经知道了这些,接下来需要面对的就是这些一个个活生生的database了.这里总结了一些一般的思路来面对一个全先的database,从而快速了解你面对的环境概要。
这也不是教科书,只是一些心得和体会,对于这种问题,每个人的认识的角度是不一样的。
1、先要了解当前的Oracle 数据库的版本和平台和相关信息
这个很重要,忙乎了半天还知道你的数据库是哪个版本,跑在什么系统上,那岂不是很悲哀,所以我个人认为这是第一步需要了解的。下面的这些脚本可以帮助你获取你需要的相关信息。
<span> <span><span>SELECT</span></span> <span>*</span> <span><span>FROM</span></span> v$version;</span>
<span> <span><span>SELECT</span></span> <span>*</span> <span><span>FROM</span></span> dba_registry_database;</span>
<span> <span><span>SELECT</span></span> dbid<span>,</span> name<span>,</span> open_mode<span>,</span> database_role<span>,</span> platform_name <span><span>FROM</span></span> v$instance;</span>
<span> <span><span>SELECT</span></span> dbms_utility<span>.</span>port_string <span><span>FROM</span></span> dual;</span>
<span> <span><span>SET</span></span> serveroutput <span><span>ON</span></span></span>
<span> declare</span>
<span> ver VARCHAR2<span>(</span><span>100</span><span>)</span>;</span>
<span> compat VARCHAR2<span>(</span><span>100</span><span>)</span>;</span>
<span> begin</span>
<span> dbms_utility<span>.</span>db_version<span>(</span>ver<span>,</span> compat<span>)</span>;</span>
<span> dbms_output<span>.</span>put_line<span>(</span><span>'Version: '</span> <span>||</span> ver <span>||</span><span>' Compatible: '</span> <span>||</span> compat<span>)</span>;</span>
<span> end;</span>
<span> <span>/</span></span>
2、其次要了解你的数据库中装了哪些组件
<span><span>SELECT</span></span><span> <span>*</span> <span><span>FROM</span></span> dba_registry</span>
3、搞清楚这个环境是单机还是集群?
这个判断方法很多,我这里给出一个借助dbms_utility来判断的方法。
<span> <span><span>SET</span></span> serveroutput <span><span>ON</span></span></span>
<span> declare</span>
<span> inst_tab dbms_utility<span>.</span>instance_table;</span>
<span> inst_cnt NUMBER; </span>
<span> begin</span>
<span> <span><span>IF</span></span> dbms_utility<span>.</span>is_cluster_database then</span>
<span> dbms_utility<span>.</span>active_instances<span>(</span>inst_tab<span>,</span> inst_cnt<span>)</span>;</span>
<span> dbms_output<span>.</span>put_line<span>(</span><span>'-'</span> <span>||</span> inst_tab<span>.</span>FIRST<span>)</span>;</span>
<span> dbms_output<span>.</span>put_line<span>(</span>TO_CHAR<span>(</span>inst_cnt<span>))</span>;</span>
<span> else</span>
<span> dbms_output<span>.</span>put_line<span>(</span><span>'Not A Clustered Database'</span><span>)</span>;</span>
<span> end <span><span>IF</span></span>;</span>
<span> end;</span>
<span> <span>/</span></span>
4、是否配置了DataGuard?
<span> <span><span>SELECT</span></span> protection_mode<span>,</span> protection_level<span>,</span> remote_archive<span>,</span> </span>
<span> database_role<span>,</span> dataguard_broker<span>,</span>guard_status</span>
<span> <span><span>FROM</span></span> v$database;</span>
5、是否起用了归档模式?
<span> conn <span>/</span> <span><span>AS</span></span> sysdba</span>
<span> archive log list;</span>
<span> <span><span>SELECT</span></span> log_mode <span><span>FROM</span></span> v$database;</span>
6、是否起用了flashback database特性?
<span> <span><span>SELECT</span></span> flashback_on <span><span>FROM</span></span> v$database;</span>
如果是,再进一步查看FRA的配置情况
7、是否起用了force logging和补充日志?
<span> <span><span>SELECT</span></span> force_logging<span>,</span>supplemental_log_data_min<span>,</span> supplemental_log_data_pk<span>,</span> </span>
<span> supplemental_log_data_ui<span>,</span>supplemental_log_data_fk<span>,</span> supplemental_log_data_all</span>
<span> <span><span>FROM</span></span> v$database;</span>
8、了解控制文件的组成
<span> <span><span>SELECT</span></span> <span>*</span> <span><span>FROM</span></span> v$controlfile;</span>
9、了解日志文件的组成
<span> <span><span>SELECT</span></span> l<span>.</span><span><span>GROUP</span></span><span><span>#, lf.type, lf.member, l.bytes, l.status LOG_STATUS, </span></span></span>
<span> lf<span>.</span><span><span>STATUS</span></span> LOGFILE_STATUS</span>
<span> <span><span>FROM</span></span> v$log l<span>,</span> v$logfile lf</span>
<span> <span><span>WHERE</span></span> l<span>.</span><span><span>GROUP</span></span><span><span># = lf.group#</span></span></span>
<span> <span><span>ORDER</span> <span>BY</span></span> <span>1</span><span>,</span><span>3</span>;</span>
10、了解参数文件的组成和位置
<span> <span><span>SHOW</span></span> parameter spfile</span>
<span> <span><span>CREATE</span></span> spfile <span><span>FROM</span></span> pfile<span>...</span></span>
<span> <span><span>CREATE</span></span> pfile <span><span>FROM</span></span> spfile;</span>
<span> <span><span>CREATE</span></span> spfile <span><span>FROM</span></span> memory;</span>
<span> <span><span>CREATE</span></span> pfile <span><span>FROM</span></span> memory; <span><span>--</span></span></span><span><span>记得这个好像是</span><span>11g</span><span>才有的语法吧</span></span>
11、了解instance的相关信息
<span> <span><span>SELECT</span></span> instance_name<span>,</span> host_name<span>,</span> <span><span>STATUS</span></span><span>,</span> archiver<span>,</span> </span>
<span> database_status<span>,</span> instance_role<span>,</span> active_state</span>
<span> <span><span>FROM</span></span> v$instance;</span>
12、用户和密码相关
是否使用了缺省密码?
是否使用了profile?
是否起用了密码验证函数?
用户身份验证的方法?
密码是否区分大小写等。
<span> <span><span>SELECT</span></span> name<span>,</span> value <span><span>FROM</span></span> gv$parameter <span><span>WHERE</span></span> name <span>=</span> <span>'resource_limit'</span>;</span>
<span> <span><span>SELECT</span></span> profile<span>,</span> resource_name<span>,</span> <span><span>LIMIT</span> <span>FROM</span></span> dba_profiles <span><span>ORDER</span> <span>BY</span></span> <span>1</span><span>,</span><span>2</span>;</span>
<span> <span><span>SELECT</span></span> username<span>,</span> profile <span><span>FROM</span></span> dba_users <span><span>WHERE</span></span> account_status<span>=</span><span>'OPEN'</span> <span><span>ORDER</span> <span>BY</span></span> <span>1</span>;</span>
<span> <span><span>SELECT</span></span> d<span>.</span>username<span>,</span> u<span>.</span>account_status</span>
<span> <span><span>FROM</span></span> dba_users_with_defpwd d<span>,</span> dba_users u</span>
<span> <span><span>WHERE</span></span> d<span>.</span>username <span>=</span> u<span>.</span>username <span><span>AND</span></span> account_status <span>=</span> <span>'OPEN'</span> </span>
<span> <span><span>ORDER</span> <span>BY</span></span> <span>2</span><span>,</span><span>1</span>;</span>
13、是否打开了BLOCK CHANGE TRACKING
<span> <span><span>SELECT</span></span> filename<span>,</span> <span><span>STATUS</span></span><span>,</span> bytes <span><span>FROM</span></span> v$block_change_tracking;</span>
14、起用了那些特性(Feature)?
DBMS_FEATURE_USAGE_REPORT
15、表空间和数据文件的规划
这个大家都很熟悉,就不写了
16、字符集相关
<span> <span><span>SELECT</span></span> <span>*</span> <span><span>FROM</span></span> database_properties;</span>
17、系统中是否存在invalid对象
<span> <span><span>SELECT</span></span> owner<span>,</span> object_type<span>,</span> COUNT<span>(*)</span></span>
<span> <span><span>FROM</span></span> dba_objects</span>
<span> <span><span>WHERE</span> <span>STATUS</span></span> <span>=</span> <span>'INVALID'</span></span>
<span> <span><span>GROUP</span> <span>BY</span></span> owner<span>,</span> object_type;</span>
18、更进一步的
是否使用了ASM?
当前系统的备份方法和策略是什么?
网络文件的配置是如何的?
19、查看一下最近的alert日志,获取一些有用的信息
20、跑几个性能分析报告,看看最近系统的运行状态如何
21、跑一个RDA报告,收集完整的系统状态报告
好了,有了这一些基本信息(不完全),你基本上对你新接触的这个系统有了一个大概的了解,接来下,你再慢慢的深入分析,然后制订出一套符合实际情况的运维规范来

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