alter日誌報錯：
Wed Apr 09 14:17:35 2014
WARNING: ASM communication error: op 0 state 0x0 (15055)
ERROR: direct connection failure with ASM
Wed Apr 09 14:22:35 2014
WARNING: ASM communication error: op 0 state 0x0 (15055)
ERROR: direct connection failure with ASM
Wed Apr 09 14:27:35 2014
WARNING: ASM communication error: op 0 state 0x0 (15055)
ERROR: direct connection failure with ASM
Wed Apr 09 14:32:36 2014
WARNING: ASM communication error: op 0 state 0x0 (15055)
ERROR: direct connection failure with ASM原因：
未加入asmdba組的用戶登錄asm實例時會報以上錯誤，通常是監控用戶創建時未指定asm磁盤的訪問權限導致。
ASM Database Instance Is Reporting: “[WARNING: ASM communication error: op 0 state 0x0 (15055)]” (文檔 ID 1665311.1)