HP Cisco MDS 9020 Cisco MDS 9000 Family Fabric Manager Configuration Guide, Re - Page 455

Chapter 23 Configuring PortChannels About PortChannels Send documentation comments to [email protected] • If you execute the write erase command on a 32-port switching module, and then copy a saved configuration to the switch from a text file that contains the no system default switchport shutdown command, you need to copy the text file to the switch again for the E ports to come up without manual configuration. • Any (or all) full line rate port(s) in the Cisco MDS 9100 Series can be included in a PortChannel. • The host-optimized ports in the Cisco MDS 9100 Series are subject to the same PortChannel rules as 32-port switching modules-only the first port of each group of 4 ports is included in a PortChannel. - You can configure only the first port in each 4-port group (for example, the first port in ports 1-4, the fifth port in ports 5-8, and so on) as an E port. If the first port in the group is configured as a PortChannel, the other three ports in each group (ports 2-4, 6-8, and so on) are not usable and remain in the shutdown state. - If any of the other three ports are configured in a no shutdown state, you cannot configure the first port to be a PortChannel. The other three ports continue to remain in a no shutdown state. Note In the Cisco MDS 9100 Series, the left most groups of ports outlined in white (4 ports in the Cisco MDS 9120 Switch and 8 ports in the Cisco MDS 9140 Switch) are full line rate like the 16-port switching module. The other ports (16 ports in the Cisco MDS 9120 Switch and 32 ports in the Cisco MDS 9140 Switch) are host-optimized like the 32-port switching module. Each group of 4 host-optimized ports have the same rules as for the 32-port switching module. About PortChanneling and Trunking Trunking is a commonly used storage industry term. However, the Cisco SAN-OS software and switches in the Cisco MDS 9000 Family implement trunking and PortChanneling as follows: • PortChanneling enables several physical links to be combined into one aggregated logical link. • Trunking enables a link transmitting frames in the EISL format to carry (trunk) multiple VSAN traffic. When trunking is operational on an E port, that E port becomes a TE port. A TE port is specific to switches in the Cisco MDS 9000 Family. An industry standard E port can link to other vendor switches and is referred to as a nontrunking interface (see Figure 23-2 and Figure 23-3). See Chapter 24, "Configuring Trunking," for information on trunked interfaces. Figure 23-2 Trunking Only Switch 1 E port Any other switch ISL E port Switch 1 Switch 2 EISL TE port TE port Trunking 79938 PortChanneling and trunking are used separately across an ISL: OL-16184-01, Cisco MDS SAN-OS Release 3.x Cisco MDS 9000 Family CLI Configuration Guide 23-3