Troubleshooting many session waiting ‘latch free'(transaction branch allocation) 11gR2
前日有套11.2.0.3 RAC on HPUX数据库环境突然出现较高的latch: free wait event, 该event在10G以后的版本较为少见（已经细化为具体latch） , 通过p1 or p2值可以确认具体latch. transaction branch allocation占用较高的db time
Month: November 2018
Troubleshooting ORA-27300 ‘fork failed with status: 11’ on SLES12 (SUSE /Linux 7)
建议在SLSE 12或以后的版本，或LINUX 7等以后的版本时，先了解一下系统变化，至少在安装RAC时， 把DefaultTasksMax修改加入到安装方档中去， 可能Oracle 在以后的安装文档或最佳实践中会增加该内容。
oracle 12cR2 新的权限组sysdg, sysbackup, sysrac, syskm
在许多公司中，各种与Oracle数据库相关的任务（如管理ASM和备份/恢复Oracle数据库）都有明确的职责分离。在过去都是使用sysdba管理所有权限如asm\DG\备份, 从Oracle Database 12c R1开始，可以使用SYSBACKUP，SYSDG和SYSKM管理权限。从Oracle Database 12cR2开始，新增加了SYSRAC管理权限..
Troubleshooting ORA-21780 during SMON to clean transient type
This issue happens on Oracle RAC environment 11.2.0.3 , db alert log show ora-21780 frequently caused by the SMON is not able to clean some objects, This short article simply record it. and how to fixed it. # db alert log Fri Nov 02 09:55:59 2018 Errors in file /oracle/app/oracle/diag/rdbms/anbob/anbob1/trace/anbob1_smon_12872.trc: ORA-21780: Maximum number of object … Read more
Oracle 12.2 Flex ASM安装RU后ASM、GIMR等资源未启动, 手动启动提示CRS-2549“it is not a valid candidate as per the placement policy”
今天遇到的一个案例，一套ORACLE 12.2 FLEX CLUSTER， 在安装了RU(20180417)后节点2的CRS启动正常，但是其它如ASM、DB、GIMR 等资源都未启动， GI alert log并未发现错误，手动使用srvctl启动ASM资源提示:
CRS-2549: Resource ‘ora.asm’ cannot be placed on ‘anbob02’ as it is not a valid candidate as per the placement policy