Veritas File System 5.1 SP1 Administrator"s Guide (5900-1499, April 2011)

To disable Concurrent I/O on a file system using the mount command
1
Shutdown the DB2 instance.
2
Unmount the file sytem using the umount command.
3
Mount the file system again using the mount command without using the -o
cio option.
Veritas File System I/O
Enabling and disabling Concurrent I/O for a DB2 database
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