What Is EIGRPv6 Passive Interface?
EIGRPv6 Passive Interface refers to a specific configuration in Enhanced Interior Gateway Routing Protocol (EIGRP) for IPv6, where an interface is set to ‘passive’. This configuration prevents EIGRPv6 from sending or receiving routing updates on that interface, conserving network resources and bandwidth. It is commonly used on interfaces where EIGRPv6 routing information is not needed or desired.
When an interface on a router is configured as a passive interface in the context of EIGRPv6, it stops the router from sending or receiving EIGRP routing updates on that interface. However, the router still includes the network connected to that interface in its EIGRP advertisements on other, non-passive interfaces.
Purpose and Benefits.
Network Security: By not sending or receiving EIGRP updates on a passive interface, this helps mitigate the risk of unauthorized access or routing information leakage.
This is particularly beneficial for interfaces connected to networks where dynamic routing updates are unnecessary or could pose a security risk.
Network Traffic Optimization: In large networks, limiting EIGRP traffic to only necessary interfaces reduces unnecessary network overhead. This can be achieved by preventing EIGRP updates on interfaces where dynamic routing is not needed, thus optimizing bandwidth.
Control and Stability: Passive interfaces in EIGRPv6 provide greater control over routing updates and network topology. By selectively choosing where to send updates, network administrators can prevent routing loops and enhance the stability of the network.
You can use the EIGRPv6 passive-interface command to control the advertisement of routing information.
The command enables the to stop routing updates over some interfaces while it allows updates to be exchanged normally over other interfaces.
We use the configuration below as an example.
How to Configure EIGRP Passive Interface.
Router(config)# ipv6 router eigrp 22
Router(config-rtr)# passive-interface g0/0
Router(config-rtr)# passive-interface g0/1
The configuration above enables the router to stop the exchange of hello packets between routers which will result in the loss of a neighbor relationship.
Therefore, it is only used on interfaces where no routers are connected.
This stops not only routing updates from being advertised but also suppresses incoming routing updates.
Use the show ipv6 protocols command to verify your configuration.
HQ#show ipv6 protocols
EIGRPv6 Passive Interface Advantages.
Configuring an interface as passive in an EIGRP for IPv6 environment serves multiple purposes:
Security: It limits the scope of where routing updates are sent, reducing the attack surface that could be exploited by malicious entities.
Network Performance: It decreases unnecessary traffic on the network, as EIGRP updates are not sent across interfaces that do not require them. This can conserve bandwidth and reduce the processing load on routers.
Administrative Control: It gives network administrators fine-grained control over the flow of routing information, allowing for more precise network behavior and the mitigation of unintended routing paths.
In conclusion, The eigrpv6 passive-interface command is a powerful tool in the configuration and optimization of EIGRP for IPv6 networks. Its appropriate application can significantly enhance the security and efficiency of a network. As you delve deeper into the study of network protocols and their configurations, understanding the strategic use of passive interfaces will be crucial in designing robust and efficient network infrastructures.
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IPv6 Routing Protocol is “ND”
IPv6 Routing Protocol is “connected”
IPv6 Routing Protocol is “eigrp 22”
EIGRP-IPv6 Protocol for AS(22)
Metric weight K1=1, K2=0, K3=1, K4=0, K5=0
NSF-aware route hold timer is 240
Router-ID: 1.1.1.1
Topology : 0 (base)
Active Timer: 3 min
Distance: internal 90 external 170
Maximum path: 16
Maximum hopcount 22
Maximum metric variance 1
Interfaces:
Serial0/0/0
GigabitEthernet0/0 (passive)
GigabitEthernet0/1 (passive)
Redistribution:
None
HQ#
EIGRP Spanning Tree Protocol (STP) VLAN Trunking Protocol (VTP)
