F And Tf Portchannels; Portchanneling And Trunking - Cisco MDS 9000 Series Configuration Manual

F and TF PortChannels

• Provides high availability on an ISL. If one link fails, traffic previously carried on this link is switched
Note
See the
for PortChannels and FSPF links.
F and TF PortChannels
An F PortChannel is also a logical interface that combines a set of F ports connected to the same Fibre Channel
node and operates as one link between the F ports and the NP ports. The F PortChannels support bandwidth
utilization and availability like the E PortChannels. F PortChannels are mainly used to connect MDS core and
NPV switches to provide optimal bandwidth utilization and transparent failover between the uplinks of a
VSAN.
An F PortChannel trunk combines the functionality and advantages of a TF port and an F PortChannel. This
logical link uses the Cisco PTP and PCP protocols over Cisco EPP (ELS).
Note
If a Cisco MDS 9124 or 9134 switch is used as a core switch, only a nontrunking F PortChannel is supported.
Trunking is not supported on this platform when NPIV enabled.

PortChanneling and Trunking

Trunking is a commonly used storage industry term. However, the Cisco NX-OS software and switches in
the Cisco MDS 9000 Series Multilayer Switches 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.
Figure 11: Trunking Only
Cisco MDS 9000 Series Interfaces Configuration Guide, Release 8.x
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to the remaining links. If a link goes down in a PortChannel, the upper protocol is not aware of it. To the
upper protocol, the link is still there, although the bandwidth is diminished. The routing tables are not
affected by link failure. PortChannels may contain up to 16 physical links and may span multiple modules
for added high availability.
Cisco MDS 9000 Series NX-OS Fabric Configuration Guide
For example, 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 Series Multilayer Switches. An industry standard E port can
link to other vendor switches and is referred to as a nontrunking interface (see
on page 220 and Figure 12: PortChanneling and Trunking, on page
page 197 for information on trunked interfaces.
Configuring PortChannels
for information about failover scenarios
Figure 11: Trunking Only,
221). See Configuring Trunking, on