SMC Networks SMC8748L2 Switch User Manual


 
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Guidelines for Creating Trunks
General Guidelines –
Finish configuring port trunks before you connect the corresponding
network cables between switches to avoid creating a loop.
A trunk can have up to 32 ports.
The ports at both ends of a connection must be configured as trunk
ports.
All ports in a trunk must be configured in an identical manner,
including communication mode (i.e., speed, duplex mode and flow
control), VLAN assignments, and CoS settings.
All the ports in a trunk have to be treated as a whole when moved
from/to, added or deleted from a VLAN via the specified
port-channel.
STP, VLAN, and IGMP settings can only be made for the entire trunk
via the specified port-channel.
Dynamically Creating a Port Channel –
Ports assigned to a common port channel must meet the following
criteria:
Ports must have the same LACP system priority.
Ports must have the same port admin key (Ethernet Interface).
If the port channel admin key (lacp admin key - Port Channel) is not
set when a channel group is formed (i.e., it has the null value of 0), this
key is set to the same value as the port admin key (lacp admin key -
Ethernet Interface) used by the interfaces that joined the group.
However, if the port channel admin key is set, then the port admin key
must be set to the same value for a port to be allowed to join a channel
group.
If a link goes down, LACP port priority is used to select the backup
link.