Disabling Quick I/O


Disabling Quick I/O
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Before disabling Quick I/O, make sure the following condition has been met:

Prerequisite

The file system you are planning to remount must be located in the /etc/filesystems file.

The file system you are planning to remount must be located in the /etc/fstab file.

For DB2: If you need to disable the Quick I/O feature, you need to remount the VxFS file system using a special mount option.

If you need to disable the Quick I/O feature, you first need to convert any Quick I/O files back to regular VxFS files. Then, remount the VxFS file system using a special mount option.

Warning:

For DB2: do not disable Quick I/O on VxFS file systems containing Quick I/O containers of type DEVICE. Doing so causes the tablespace containing them to go offline.

To remount the file system with Quick I/O disabled For DB2

Use the mount -o noqio command as follows:

# /opt/VRTS/bin/mount -V vxfs -o remount,noqio special
					/mount_point

For example, to remount file system db01 with Quick I/O disabled:

# /opt/VRTS/bin/mount -V vxfs -o remount,noqio \
 /dev/vx/dsk/dbdg/vol01 /db01

To disable Quick I/O for DB2

If the database is active, make it inactive by either shutting down the instance or disabling user connections.
To remount the file system with Quick I/O disabled, use the command as follows:
```
# /opt/VRTS/bin/mount -V vxfs -o remount,noqio /mount_point
```

To disable Quick I/O for Sybase

If the database is running, shut it down.
To remount the file system with Quick I/O disabled, use the command as follows:
```
# /opt/VRTS/bin/mount -V vxfs -o remount,noqio /mount_point
```

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