Setting the data transfer speed of FICON ports

Use the following procedure to set the data transfer speed of a 32-Gbps FICON^® port (FICON32G) using CCI. For details about the CCI commands, see the Command Control Interface Command Reference.

When configuring the data transfer speed of a 32-Gbps FICON^® port, observe the following precautions:

• If the transfer speed is set to Auto, a speed lower than the maximum supported speed might be applied. To avoid this risk of performance degradation, select the maximum supported speed from 8 Gbps, 16 Gbps, or 32 Gbps. Therefore, confirm in advance the maximum data transfer speed of the host HBA or the switch.
• The host HBA or switch must support a maximum data transfer speed of 8 Gbps or higher.
• All hosts connected to the FICON^® port being configured must have completed channel path offline operations.

  This is a function for IBM^® mainframe systems that disables the channel path (the path between the host and the FICON^® port).

• The link between the FICON^® port and the host HBA, or between the FICON^® port and the switch, must be in a link-down state.

  If the data transfer speed is set while the link is up, the CCI command may complete successfully, but the new speed will not be applied to the FICON^® port. Therefore, configure the setting while the link is down. If the setting was applied while the link was up, perform link-down and link-up operations as follows:

  • If the FICON^® port is directly connected to the host HBA: Execute channel path offline on the host, and then execute channel path online.
  • If the FICON^® port is connected to a switch: Set the switch port to disable (link-down), and then set it to enable (link-up). Refer to the switch manual for details. Alternatively, ask the service representative to unplug the cable (link-down) and reinsert it (link-up).