Cisco Nexus 5000 Series Switch Fabric Manager Software Configuration Guide, NX-OS 4.0 (OL-16598-01, June 2008)

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Nexus 5000 Series Switch Fabric Manager Software Configuration Guide
OL-16598-01
Chapter 14 Configuring SAN Port Channels
Configuring SAN Port Channels
The SAN port channel is created. It may take a few minutes before the new port channel is visible in the
Fabric pane.
About SAN Port Channel Modes
You can configure each SAN port channel with a channel group mode parameter to determine the port
channel protocol behavior for all member ports in this channel group. The possible values for a channel
group mode are as follows:
• On (default)—The member ports only operate as part of a SAN port channel or remain inactive. In
this mode, the port channel protocol is not initiated. However, if a port channel protocol frame is
received from a peer port, the software indicates its nonnegotiable status. Port channels configured
in the On mode require you to explicitly enable and disable the port channel member ports at either
end if you add or remove ports from the port channel configuration. You must physically verify that
the local and remote ports are connected to each other.
• Active—The member ports initiate port channel protocol negotiation with the peer port(s) regardless
of the channel group mode of the peer port. If the peer port, while configured in a channel group,
does not support the port channel protocol, or responds with a nonnegotiable status, it will default
to the On mode behavior. The Active port channel mode allows automatic recovery without
explicitly enabling and disabling the port channel member ports at either end.
Table 14-1 compares On and Active modes.
Table 14-1 Channel Group Configuration Differences
On Mode Active Mode
No protocol is exchanged. A port channel protocol negotiation is performed
with the peer ports.
Moves interfaces to the suspended state if its
operational values are incompatible with the SAN
port channel.
Moves interfaces to the isolated state if its
operational values are incompatible with the SAN
port channel.
When you add or modify a port channel member
port configuration, you must explicitly disable
(shut) and enable (no shut) the port channel
member ports at either end.
When you add or modify a port channel interface,
the SAN port channel automatically recovers.
Port initialization is not synchronized. There is synchronized startup of all ports in a
channel across peer switches.
All misconfigurations are not detected as no
protocol is exchanged.
Consistently detect misconfigurations using a port
channel protocol.
Transitions misconfigured ports to the suspended
state. You must explicitly disable (shut) and
enable (no shut) the member ports at either end.
Transitions misconfigured ports to the isolated
state to correct the misconfiguration. Once you
correct the misconfiguration, the protocol ensures
automatic recovery.
This is the default mode. You must explicitly configure this mode.