Situation: the client has a SQL server 2008 R2. They had a problem to access some of database. There are some Events:
Event ID: 823
Description:
The operating system returned error 21(The device is not ready.) to SQL Server during a read at offset 0x00000000322000 in file ‘R:\MSSQL\HSADB DATA\M846_Sub.mdf’. Additional messages in the SQL Server error log and system event log may provide more detail. This is a severe system-level error condition that threatens database integrity and must be corrected immediately. Complete a full database consistency check (DBCC CHECKDB). This error can be caused by many factors; for more information, see SQL Server Books Online.
Troubleshooting: The Database is located in EqaulLogic SAN. There are 4 NICs connecting to the SAN. However, EqualLogic SAN Management shows there are only two are active.
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