記錄一則DG遭遇ORA-00088的案例

測試環境：RHEL 5.4 + Oracle 11.2.0.3 DG
現象：起初是在使用DG Broker進行switchover切換測試時，報錯ORA-16775，提示有可能有數據丟失，不容許switchover.

DGMGRL> switchover to prod1
Performing switchover NOW, please wait...
Error: ORA-16775: target standby database in broker operation has potential data loss

Failed.
Unable to switchover, primary database is still "sbdb1"

進一步查詢歸檔傳輸狀況，發現最新的幾個歸檔都沒有傳輸成功，此時alert尚未報錯，但能夠經過查詢v$archive_dest確認錯誤信息：

SQL> select error from v$archive_dest where dest_id = 2;

ERROR
-----------------------------------------------------------------
ORA-00088: command cannot be executed by shared server

錯誤的提示很是明確了，再看下oerr的幫助：

$ oerr ora 88
00088, 00000, "command cannot be executed by shared server "
// *Cause:  Debug command issued on shared server.
// *Action: Reissue the command using a dedicated server.

問題明確了，處理起來也很是簡單，進一步檢查發現tnsnames.ora中的配置沒有顯示指定(SERVER = DEDICATED),而剛好數據庫配置了共享鏈接。因此咱們只須要修改顯示指定(SERVER = DEDICATED)便可，例如這樣：

PROD1 =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = xxx01.example.com)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)      --這裏顯示指定
      (SERVICE_NAME = PROD1.us.oracle.com)
    )
  )

注意主備庫都須要同步修改，修改完成後，沒有再進行任何操做，就能夠看到以前沒有傳輸的歸檔自動傳輸成功。
此時再次進行switchover切換測試就能夠成功了。