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Loopback interface

7.2.3
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7.4.1
7.4.0
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7.2.7
7.2.6
7.2.5
7.2.4
7.2.3
7.2.2
7.2.1
7.2.0
7.0.15
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7.0.12
7.0.11
7.0.10
7.0.9
7.0.8
7.0.7
7.0.6
7.0.5
7.0.4
7.0.3
7.0.2
7.0.1
7.0.0
6.4.15
6.4.14
6.4.13
6.4.12
6.4.11
6.4.10
6.4.9
6.4.8
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6.4.6
6.4.5
6.4.4
6.4.3
6.4.2
6.4.1
6.4.0
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Loopback interface

A loopback interface is a logical interface that is always up. Its IP address does not depend on one specific physical port, and the attached subnet is always present in the routing table. Therefore, it can be accessed through several physical or VLAN interfaces.

Typically, a loopback interface can be used with management access, BGP peering, PIM rendezvous points, and SD-WAN.

Loopback interfaces require appropriate firewall policies to allow traffic to and from the interfaces. Multiple loopback interfaces can be configured in either non-VDOM mode or in each VDOM.

Dynamic routing protocols can be enabled on loopback interfaces. For example, loopback interfaces are a good practice for OSPF. To make it easier to troubleshoot OSPF, set the OSPF router ID to the same value as the loopback IP address to access a specific FortiGate using that IP address and SSH.

A loopback interface is configured using similar steps as a physical interface (see Configuring an interface).

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Loopback interface

A loopback interface is a logical interface that is always up. Its IP address does not depend on one specific physical port, and the attached subnet is always present in the routing table. Therefore, it can be accessed through several physical or VLAN interfaces.

Typically, a loopback interface can be used with management access, BGP peering, PIM rendezvous points, and SD-WAN.

Loopback interfaces require appropriate firewall policies to allow traffic to and from the interfaces. Multiple loopback interfaces can be configured in either non-VDOM mode or in each VDOM.

Dynamic routing protocols can be enabled on loopback interfaces. For example, loopback interfaces are a good practice for OSPF. To make it easier to troubleshoot OSPF, set the OSPF router ID to the same value as the loopback IP address to access a specific FortiGate using that IP address and SSH.

A loopback interface is configured using similar steps as a physical interface (see Configuring an interface).

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