300-425 · Question #346
A university has three campus locations and the main data center. Each campus location has a Cisco Catalyst 9800-40 WLC that manages 600 APs. The data center has a Catalyst 9800-40 WLC, which serves…
The correct answer is A. The data center WLC and Campus1 WLC are the high availability SSO pair. Campus3 APs have. The only way to meet the requirement for Campus1 to operate with zero downtime is to implement Stateful Switchover (SSO) High Availability. SSO requires two controllers to be physically paired (Active/Standby). Since only two new WLCs were approved, and the budget is restricted…
Question
A university has three campus locations and the main data center. Each campus location has a Cisco Catalyst 9800-40 WLC that manages 600 APs. The data center has a Catalyst 9800-40 WLC, which serves as an N+1 backup for each campus WLC. A consulting engineer must install four additional Catalyst 9800-40 WLCs to serve as the high availability SSO pair for each campus, but only two have been approved due to budget restrictions. The new WLCs must be implemented using these requirements:
- Data center WLC must always be available as N+1 backup to either
campus WLC.
- Campus1 WLC must operate with zero downtime.
- In the event of multiple campus outages, the AP priority order is to
support Campus3, Campus2, and then Campus1.
- No APs on campus can be left stranded without a WLC in the event of
an outage. What design approach must the consulting engineer take?
Options
- AThe data center WLC and Campus1 WLC are the high availability SSO pair. Campus3 APs have
- BThe data center WLC and Campus3 WLC are the high availability SSO pair. Campus1 APs have
- CThe Campus1 WLC is the high availability SSO pair. The data center WLC is split into two WLCs,
- DThe Campus3 WLC is the high availability SSO pair. The data center WLC is split into two WLCs,
How the community answered
(59 responses)- A68% (40)
- B7% (4)
- C5% (3)
- D20% (12)
Explanation
The only way to meet the requirement for Campus1 to operate with zero downtime is to implement Stateful Switchover (SSO) High Availability. SSO requires two controllers to be physically paired (Active/Standby). Since only two new WLCs were approved, and the budget is restricted to these two plus the existing WLCs, the engineer must pair the existing Campus1 WLC with the existing Data Center WLC to form the SSO pair. This satisfies the zero-downtime requirement for Campus1. The remaining campus WLCs (Campus2 and Campus3) must then be configured with an N+1 roaming redundancy list pointing to the SSO pair as the highest-priority controller in case their local WLC fails. The AP priorities are configured to dictate which campus's APs take precedence in joining the WLCs when the WLC capacity is exceeded. In the event of multiple campus outages, the APs will fail over to the remaining WLCs based on their priority. The requirement specifies the failover priority should be Campus3, Campus2, and then Campus1. The AP Priority configuration is inversely proportional to the preference, where 1 is the highest preference and 4 is the lowest. Therefore, the priorities must be set as: - Campus3 APs: Priority 1 (Highest) - Campus2 APs: Priority 2 - Campus1 APs: Priority 4 (Lowest, as it is already protected by SSO) This configuration ensures Campus3 APs are served first by the available capacity on the Data Center/Campus1 SSO pair, followed by Campus2, if both their local WLCs fail.
Topics
Community Discussion
No community discussion yet for this question.