一.问题描述
sqlplus启动一节点实例，报如下错：
Total System Global Area 6.4425E+10 bytes
Fixed Size 7651632 bytes
Variable Size 9932119760 bytes
Database Buffers 5.4358E+10 bytes
Redo Buffers 126558208 bytes
ORA-00221: error on write to control file
ORA-00206: error in writing (block 1, # blocks 1) of control file
ORA-00202: control file: '+MDCCSSDG1/CCSSVER/CONTROLFILE/control01.ctl'
ORA-15081: failed to submit an I/O operation to a disk
ORA-15081: failed to submit an I/O operation to a disk

Oracle版本：ORACLE 12.1.0.2 + psu 20160719

二.问题分析
1.检查alert.log
cd /mdccssver/mdccssver/orabase/diag/rdbms/ccssver/ccssver2/trace
rw-r----- 1 ccssver oinstall 2043 Sep 14 13:56 ccssver2_ora_2538.trc
-rw-r----- 1 ccssver oinstall 1550 Sep 14 13:56 ccssver2_m000_2592.trc
-rw-r----- 1 ccssver oinstall 233 Sep 14 13:56 ccssver2_m000_2592.trm
-rw-r----- 1 ccssver asmadmin 40400051 Sep 14 13:57 alert_ccssver2.log
-rw-r----- 1 ccssver oinstall 1661 Sep 14 13:57 ccssver2_lmon_2376.trm
-rw-r----- 1 ccssver oinstall 10621 Sep 14 13:57 ccssver2_lmon_2376.trc
-rw-r----- 1 ccssver oinstall 114 Sep 14 13:58 ccssver2_lmhb_2414.trm
-rw-r----- 1 ccssver oinstall 1273 Sep 14 13:58 ccssver2_lmhb_2414.trc

tail -100 alert_ccssver2.log|more
ARNING: Write Failed. group:1 disk:1 AU:221 offset:16384 size:16384
path:/dev/asmdisk/datadisk2
incarnation:0x12 asynchronous result:'I/O error'
subsys:System krq:0xffffffff7cd27dd0 bufp:0xffffffff7c6e7e00 osderr1:0x69a1 osderr2:0x0
IO elapsed time: 0 usec Time waited on I/O: 0 usec
Wed Sep 14 13:56:24 2016
Errors in file /mdccssver/mdccssver/orabase/diag/rdbms/ccssver/ccssver2/trace/ccssver2_ora_2538.trc:
ORA-15080: synchronous I/O operation failed to write block 1 of disk 1 in disk group MDCCSSDG1
ORA-27041: unable to open file
SVR4 Error: 13: Permission denied
Additional information: 3
WARNING: failed to write mirror side 1 of virtual extent 0 logical extent 0 of file 264 in group 1 on disk 1 allocation unit 221
WARNING: group 1 file 264 vxn 0 block 1 write I/O failed
Wed Sep 14 13:56:24 2016
Errors in file /mdccssver/mdccssver/orabase/diag/rdbms/ccssver/ccssver2/trace/ccssver2_ora_2538.trc:
ORA-00206: error in writing (block 1, # blocks 1) of control file
ORA-00202: control file: '+MDCCSSDG1/CCSSVER/CONTROLFILE/control01.ctl'
ORA-15081: failed to submit an I/O operation to a disk
ORA-15081: failed to submit an I/O operation to a disk
ORA-221 signalled during: ALTER DATABASE MOUNT...
上面报错说明读写MDCCSSDG1磁盘组有异常。

2.查看ASM磁盘和磁盘组状态：

SQL> select name,MOUNT_STATUS,HEADER_STATUS,MODE_STATUS,STATE,PATH from v$asm_disk;