alter日志报错：

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组的用户登录asm实例时会报以上错误，通常是监控用户创建时未指定asm磁盘的访问权限导致。

ASM Database Instance Is Reporting: “[WARNING: ASM communication error: op 0 state 0x0 (15055)]” (文档 ID 1665311.1)