Oracle常見錯誤

1、 Oracle無法動态注冊

      在SQL*PLUS下多次輸入alter system register.監聽器的狀态始終顯示為The listener supports no services。

      可檢視listener.ora裡面的IP或主機名是否與/etc/hosts裡面的相對應。

2、 ORA-00845: MEMORY_TARGET not supported on this system

      Oracle解釋如下：

[oracle@node3 ~]$ oerr ora 845
00845, 00000, "MEMORY_TARGET not supported on this system"
// *Cause: The MEMORY_TARGET parameter was not supported on this operating system or /dev/shm was not sized correctly on Linux.
// *Action: Refer to documentation for a list of supported operating systems. Or, size /dev/shm to be at least the SGA_MAX_SIZE on each Oracle instance running on the system.      

     其實，在啟動過程中，告警日志會報以下錯誤：

WARNING: You are trying to use the MEMORY_TARGET feature. This feature requires the /dev/shm file system to be mounted for at least 369098752 bytes. /dev/shm is either not mounted or is mounted with available space less than this size. Please fix this so that MEMORY_TARGET can work as expected. Current available is 261324800 and used is 0 bytes. Ensure that the mount point is /dev/shm for this directory.
memory_target needs larger /dev/shm      

     原因：AMM是11g引入的新特性，它會利用到Linux系統中的/dev/shm，/dev/shm必須大于或等于memory_target。

     解決方法：

     1> 立即生效--注意：/dev/shm的size值必須為整數,預設是記憶體的一半

[root@node3 oracle]# umount tmpfs
[root@node3 oracle]# mount -t tmpfs shmfs -o size=400m /dev/shm      

     2> 修改/etc/fstab    

tmpfs                   /dev/shm                tmpfs   defaults,size=400m      0 0      

     也可以先修改/etc/fstab,然後用 mount -o remount /dev/shm重新挂載/dev/shm

     在RHEL6以上是系統的一個bug，即便在/etc/fstab中修改了/dev/shm的值，重新開機後依然恢複到記憶體的一半。

     https://bugzilla.redhat.com/show_bug.cgi?id=669700，關于網上說的修改/etc/rc.d/rc.sysinit檔案，經測試，仍然無法解決問題，反而會導緻其它的盤沒有挂載。

     最後，隻能将 mount -o remount /dev/shm編輯到/etc/rc.local檔案中

3. ORA-29701: unable to connect to Cluster Synchronization Service

    手動啟動CSS：crsctl start res ora.cssd

4. ORA-12641: Authentication service failed to initialize

    看一下$ORACLE_HOME/network/admin/sqlnet.ora檔案中SQLNET.AUTHENTICATION_SERVICES的參數是否為all了。