New Training: Configure Overlay Transport Virtualization (OTV)
In this 5-video skill, CBT Nuggets trainer Jeff Kish deploys OTV into a virtual lab environment. Configuration includes OTV multicast and unicast deployments, as well as advanced configuration like FHRP blocking. Watch this new Cisco training.
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Cisco CCNP Data Center
This training includes:
50 minutes of training
You’ll learn these topics in this skill:
Setting up the OTV Environment
Configuring OTV FHRP Blocking
Review and Quiz
Why You Need to Filter FHRP Messages for OTV
OTV (overlay transport virtualization) is a technology that extends the traditional datacenter interconnect through IP technologies. It is built from the ground up to provide Layer 2 extension capabilities over any transport infrastructure. Its only requirement is that an IP-based connectivity method is provided between remote data centers.
It is common when connecting two distant datacenters with OTV that both may use the same default gateway. Because multiple sites might use the same VLAN/IP subnet, it is possible that FHRP (first-hop redundancy protocol) messages are exchanged freely. That could lead to the election of a single default gateway which would cause sub-optimal network traffic routes.
Due to that, OTV is capable of filtering those messages, and it is recommended to enable filtering of FHRP messages. This will allow the same FHRP configuration to be used in different sites. That means the same default gateway is available by the same virtual IP and MAC addresses in each data center which will allow outbound traffic to traverse the most optimal and shortest path.