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What is the Overlay Transport Virtualization site VLAN used for?
A. to allow the join interfaces at different sites to communicate
B. to detect devices at the site that are not capable of OTV
C. to allow multiple site AEDs to communicate with each other
D. to detect other OTV edge devices in the site
Correct Answer: D
Explanation/Reference:
Explanation:
The edge device performs OTV functions: it receives the Layer 2 traffic for all VLANs that need to be extended to remote locations and dynamically encapsulates the Ethernet frames into IP packets that are then sent across the transport infrastructure. It is expected that at least two OTV edge devices are deployed at each data center site to improve the resiliency. http://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Data_Center/DCI/whitepaper/DCI3_OT V_Intro/DCI_1.html
Site vlan
• By default, OTV uses VLAN 1 as the site VLAN
○ It is recommended that you use a different, dedicated VLAN
• The Site VLAN is not extended across the OTV
○ Therefore, you can use the same VLAN for both sites.
• The Site VLAN is used to group OTV edge devices of a single site
○ but even if you are using only one OTV edge device per site, you still need to configure a site VLAN
• The “otv site-vlan vlan” command configures a VLAN that all local edge devices in a site communicate on.
• OTV uses this Site VLAN to send hello messages that other configured edge devices in the site respond to.
• OTV uses a VLAN hashing algorithm to select the AED (authoritative edge device) from one of these local site edge devices.