Why OSPF is not used in DMVPN?

OSPF is challenged in the DMVPN arena for one particular reason; As the hubs have a single tunnel interface, the spokes that connect to it all have to be in the same area. This will limit scalability, which may or may not be a concern to you. If you’re going to use OSPF, make sure that your hubs are the DR and BDR.

What are the steps to configure OSPF?

Configuring OSPF in a Single Area

Step 1 Use the command router ospf process ID to start OSPF.
Step 2 Use the network command to enable the interfaces.
Step 3 Identify area assignments.
Step 4 (Optional) Assign the router ID.

Can we have OSPF run over a GRE tunnel?

To run OSPF over IPSec tunnels, a Layer 3 GRE tunnel is configured between two routers with GRE destination addresses as the inner address of the IPsec tunnel. OSPF is enabled on the Layer 3 GRE tunnel interface, and all of the OSPF control packets undergo GRE encapsulation before entering the IPsec tunnels.

What is DMVPN configuration?

DMVPN as a design concept is essentially the configuration combination of protected GRE Tunnel and Next Hop Routing Protocol (NHRP).

What is the difference between ipsec and DMVPN?

Both IPSEC and DMVPN uses public network like internet but the main difference is IPSEC is always point to point while DMVPN is Point to multipoint terminology. IPSEC tunneling is always spoke to spoke while DMVPN is always hub to Spoke or you can have hub to spokes multi-tunneling.

What is a DMVPN router?

A dynamic multipoint virtual private network (DMVPN) is a secure network that exchanges data between sites/routers without passing traffic through an organization’s virtual private network (VPN) server or router, located at its headquarters.

How will you configure OSPF in an interface?

Step-by-Step Procedure

  1. Configure the interface. [edit]user@host# set interfaces at-0/1/0 unit 0 family inet address 192.0.2.2.
  2. Create an OSPF area. [edit]user@host# edit protocols ospf area 0.0.0.1.
  3. Assign the interface to the area and specify the neighbor.
  4. If you are done configuring the device, commit the configuration.

Which two commands are used to configure a basic OSPF configuration?

OSPF Basic Configuration Commands A number of different Cisco IOS OSPF configuration commands are available, but at its most basic, OSPF configuration uses three commands: the router ospf, network, and router-id commands. The router ospf process-id command is the beginning of any Cisco IOS OSPF configuration.

What is a virtual link in OSPF?

Virtual links are used to extend Area 0 across another area. They also can be thought of as tunnels for LSAs. They are deployed in cases when areas become partitioned or an area does not border Area 0.

At which interval does OSPF refresh LSAs?

The OSPF standard requires that every LSA be refreshed every 30 minutes. The Juniper Networks implementation refreshes LSAs every 50 minutes. By default, any LSA that is not refreshed expires after 60 minutes.

What protocols does DMVPN use?

Routing protocols One option is to use Open Shortest Path First (OSPF) as the interior routing protocol. OSPF is best suited for small-scale DMVPN deployments. For large-scale implementations, the Enhanced Interior Gateway Routing Protocol (EIGRP) or Border Gateway Protocol (BGP) are more suitable.

What is the difference between DMVPN and MPLS?

DMVPN supports Spoke-to-Spoke encrypted tunnels over the Internet which is less stable than carrier network. MPLS VPNs are typically in service provider networks and large campus networks where voice and video reliability is also key requirement.