Remove old paths from hosts

After the host detects the paths to the new I/O group, you must remove all the old paths from the host.

Because the system can support many different kinds of hosts, these steps use a Linux (RHEL 6.1 or SLES 11 SP1) host as an example. For instructions on completing these tasks for other Fibre Channel hosts, see the documentation that accompanies your host systems.

Note: The instructions assume that all volumes are mapped to Fibre Channel hosts. For instructions on moving volumes that are mapped to iSCSI hosts, see Moving volumes mapped to iSCSI hosts to another I/O group

The system supports many different host systems and host bus adapters (HBA). The following website provides current interoperability information. This information includes current support information, such as maximum configuration details, technical flashes, hints, and tips, host systems, operating system levels, HBAs, cables, and fabrics that are supported.

To remove the old paths on a Linux system (These steps use RHEL 6.1 or SLES 11 SP1.), complete these steps:

Determine the paths that are related to the old I/O group and ensure that the paths display Failed Faulty status by submitting the following command:
```
echo offline > /sys/block/sdX/device/state
```
If the paths do not display Failed Faulty, wait until the status changes before proceeding.
After the status of the old paths that are to the old I/O group displays Failed Faulty, submit the following command to delete each path:
```
echo 1 > /sys/block/sdX/device/delete
```
Run the following command to verify that the paths that are related to the old caching I/O group are removed:
```
multipath -ll
```