Netgear M5300-28G-POE+ (GSM7228PSv1h2) - 12-Port Managed Gigabit Switch Ratgeber Für Administratoren
MLAGs
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Managed Switches
Multichassis Link Aggregation Concepts
In a Layer 2 network, Spanning Tree Protocol (STP) is deployed to avoid network loops. With
STP running, ports can either be in forwarding or in blocked state. When a topology change
occurs, STP reconverges the network to a new stable loop-free network. STP is successful in
managing Layer 2 networks and mitigating loops in the network.
STP running, ports can either be in forwarding or in blocked state. When a topology change
occurs, STP reconverges the network to a new stable loop-free network. STP is successful in
managing Layer 2 networks and mitigating loops in the network.
However, because STP marks ports as forwarding or blocking, a significant percentage of the
links in a network do not carry data traffic. Also, any disruption in existing links causes a
reconvergence of up to several seconds.
links in a network do not carry data traffic. Also, any disruption in existing links causes a
reconvergence of up to several seconds.
New loop management technologies include Spanning Tree Bridges and Transparent
Interconnection of Lots of Links (TRILL), and a multichassis LAG (MLAG) solution such as
Virtual Private Cloud (VPC).
Interconnection of Lots of Links (TRILL), and a multichassis LAG (MLAG) solution such as
Virtual Private Cloud (VPC).
To avoid using STP, you can bundle together multiple links between two adjacent switches
using a link aggregation group (LAG). The advantages of a LAG are that all member links are
in forwarding state and a link failure does not cause disruptions in the order of seconds (a
LAG handles a link failure in less than one second). However, if a device failure occurs in a
typical LAG setting, the network can go down.
using a link aggregation group (LAG). The advantages of a LAG are that all member links are
in forwarding state and a link failure does not cause disruptions in the order of seconds (a
LAG handles a link failure in less than one second). However, if a device failure occurs in a
typical LAG setting, the network can go down.
A multichassis LAG (MLAG) carries the advantages of a LAG across multiple devices. An
MLAG enables links that are on two different switches to pair with links on a partner device.
The remote partner device does not detect that it is pairing with two different devices to form
a LAG. The advantages of an MLAG are that all links can carry data traffic simultaneously,
and if a link or device failure occurs, the network can be resolved and the traffic can resume
quickly.
The remote partner device does not detect that it is pairing with two different devices to form
a LAG. The advantages of an MLAG are that all links can carry data traffic simultaneously,
and if a link or device failure occurs, the network can be resolved and the traffic can resume
quickly.
The following figure shows an example of an MLAG deployment topology.