Usually the bridge ID would have to be altered on all four switches to obtain the desired result.
For example for VLAN 3 the bridge priority on SW A could be 0 making this the root bridge for VLAN 3.
The bridge priority on SW C could be 4096. Therefore traffic will flow directly down to SW A assuming SW A is assuming the Active role in your FHRP.
When using HSRP for example with STP you must make sure both protocols align to each other, so that the root bridge that is receiving traffic is also assuming the Active FHRP role. Otherwise in this example, traffic will flow the long way round leading to sub-optimal flow of traffic.
The answer is C and D due to the ALT and BLK port existing on these switches which provides the failover.
If you recall STP will block ports on a non-root switch (SW C or D), they are not blocked on the root bridge.
Try the example in a Packet Tracer lab and you will see that the ALT or BLK ports are positioned on a non-root switch, remember every non-root switch must either BLK or have an ALT port to the root bridge to prevent loops! This is what provides the almost seamless failover on rSTP.
All ports on the root bridge are designated ports.
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Cisco’s software-defined wide area network (SD-WAN) solution allows user to quickly and seamlessly establish an overlay fabric to connect an enterprise’s data centers, branch and campus locations, as well as colocation facilities in order to imp...
1. Log into CLI of DNAC:
ssh maglev@< DNAC appliance IP> -p 2222
2. Run this curl command to get token to get member id:
curl -X POST -u admin:<admin user password> -H -V https://<CLUSTER-IP>/api/system/v1/identitymgmt/token
Enterprise Switching Business Unit is glad to announce Beta release 16.12.2 for all Catalyst 9200/9300/9400/9500/9600 and Catalyst 3650/3850 Platforms. This release is made available to allow users to test, evaluate and share fee...
Purpose of the document
This document describes the general recommendations or best practices when designing and deploying the Cisco SD-Access technology. The document assumes that the reader has a general overview of Cisco's SD-Access for Distributed C...