Quanta Cloud Technology QuantaMesh QNOS5, Configuration Manual

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The General mode port can then be configured as a tagged or untagged member of any VLAN, as shown in
“VLAN Configuration Example”.
3.3. Port-channels – Operation and Configuration
Port-channel allows one or more full-duplex (FDX) Ethernet links of the same speed to be aggregated
together to form a Port-channel. This allows the switch to treat the Port-channel as if it is a single link. The
primary purpose of Port-channels is to increase the overall bandwidth between two switches. This is
accomplished by effectively aggregating multiple ports together that act as a single, logical connection
between the two switches. Port-channels also provide redundancy. If a link fails, traffic is automatically
redistributed across the remaining links.
QNOS software supports industry-standard Port-channels that adhere to the IEEE 802.3ad specification. Both
static and dynamic Port-channels are supported. Each Port-channel can have a maximum of 32 ports as
members (as long as the platform can support it). You can configure Port-channels until all switch ports are
assigned to a Port-channel.
Figure 4 shows an example of a switch in the wiring closet connected to a switch in the data center by a
Port-channel that consists of four physical 10 Gbps links. The Port-channel provides full-duplex bandwidth
of 40 Gbps between the two switches.
Figure 3-4: Port-channel Configuration
3.3.1. Static and Dynamic Port-channel
Port-channel can be configured as either dynamic or static. Dynamic configuration is supported using the
IEEE 802.3ad standard, which is known as Link Aggregation Control Protocol (LACP). Static configuration is
used when connecting the switch to an external Gigabit Ethernet switch that does not support LACP.
One advantage of LACP is that the protocol enables the switch to confirm that the external switch is also
configured for Port-channel. When using static configuration, a cabling or configuration mistake involving the
local switch or the external switch could go undetected and thus cause undesirable network behavior. Both
static and dynamic Port-channels (via LACP) can detect physical link failures within the Port-channel and
continue forwarding traffic through the other connected links within that same Port-channel. LACP can also
detect switch or port failures that do not result in loss of link. This provides a more resilient Port-channel.
Best practices suggest using dynamic link aggregation instead of static link aggregation. When a port is
added to a Port-channel as a static member, it neither transmits nor receives LACP PDUs.
3.3.2. Port-channel Hashing