Cisco Systems 3750E manual Eigrp Nonstop Forwarding, 38-38

Chapter 38 Configuring IP Unicast Routing

Configuring EIGRP

Table 38-7	Default EIGRP Configuration (continued)
Feature		Default Setting
NSF1 Awareness		Enabled2. Allows Layer 3 switches to continue forwarding packets
		from a neighboring NSF-capable router during hardware or software
		changes.
NSF capability		Disabled.
		Note The Catalyst 3750-E switch supports EIGRP NSF-capable
		routing for IPv4.
Offset-list		Disabled.
Router EIGRP		Disabled.
Set metric		No metric set in the route map.
Traffic-share		Distributed proportionately to the ratios of the metrics.
Variance		1 (equal-cost load-balancing).

1.NSF = Nonstop Forwarding

2.EIGRP NSF awareness is enabled for IPv4 on Catalyst 3750-E and 3560-E switches running the IP services feature set.

To create an EIGRP routing process, you must enable EIGRP and associate networks. EIGRP sends updates to the interfaces in the specified networks. If you do not specify an interface network, it is not advertised in any EIGRP update.

Note If you have routers on your network that are configured for IGRP, and you want to change to EIGRP, you must designate transition routers that have both IGRP and EIGRP configured. In these cases, perform Steps 1 through 3 in the next section and also see the “Configuring Split Horizon” section on page 38-24. You must use the same AS number for routes to be automatically redistributed.

EIGRP Nonstop Forwarding

The switch stack supports two levels of EIGRP nonstop forwarding:

•EIGRP NSF Awareness, page 38-38

•EIGRP NSF Capability, page 38-39

EIGRP NSF Awareness

The IP-services feature set supports EIGRP NSF Awareness for IPv4. When the neighboring router is NSF-capable, the Layer 3 switch continues to forward packets from the neighboring router during the interval between the primary Route Processor (RP) in a router failing and the backup RP taking over, or while the primary RP is manually reloaded for a nondisruptive software upgrade.

This feature cannot be disabled. For more information on this feature, see the “EIGRP Nonstop Forwarding (NSF) Awareness” section of the Cisco IOS IP Routing Protocols Configuration Guide, Release 12.4 at this URL:

http://www.cisco.com/en/US/products/ps6350/products_configuration_guide_chapter09186a00804529 72.html

	Catalyst 3750-E and 3560-E Switch Software Configuration Guide
38-38	OL-9775-02