Administrator Guide

Enabling MPIO on Windows
1. Start Server Manager if it is not already running.
2. In the Manage menu, select Add Roles and Features.
3. In the Add Roles and Features Wizard, select Role-based or Feature Based Installation.
4. Click Next.
5. Select the server from the pool and then click Next.
6. Click Next again to go to the feature selection window.
7. Select the Multipath IO checkbox and then click Next.
8. Click Install.
9. When prompted, reboot the system.
When the reboot is complete, MPIO is ready to use.
Enabling MPIO on Linux
1. Run the following command to ensure that the multipath daemon is installed and set to start at run-time:
chkconfig multipathd on
2. Ensure the correct entries exist in the /etc/multipath.conf file on each OSS/MDS host. Create a separate device entry for the ME4
Series storage system. The following table specifies four attributes that should be set. Run the following command to obtain the exact
vendor and product ID values:
multipath -v3
Attribute
Value
prio alua
failback immediate
vendor vendor-name
product product-ID
3. Run the following command to reload the multipath.conf file:
service multipathd reload
4. Run the following command to determine if the multipath daemon used ALUA to obtain the optimal/non-optimal paths:
multipath -v3 | grep alua
You should see output stating that ALUA was used to configure the path priorities. For example:
Oct 01 14:28:43 | sdb: prio = alua (controller setting) Oct 01 14:28:43 | sdb: alua prio =
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Physical port selection
In a system configured to use either all FC or all iSCSI ports, use the ports in the following order:
1. A0,B0
2. A2,B2
3. A1,B1
4. A3,B3
The reason for doing so is that each pair of ports (A0,A1 or A2,A3) are connected to a dedicated CNC chip. If you are not using all four
ports on a controller, it is best to use one port from each pair (A0,A2) to ensure better I/O balance on the front end.
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Best practices