Table Of Contents
N Commands
This chapter describes the Cisco NX-OS unicast routing commands that begin with the letter N.
neighbor
To configure a BGP neighbor (router, vrf) and enter the neighbor configuration mode, use the neighbor router BGP configuration mode command. To remove an entry, use the no form of this command.
neighbor {ip-addr | ip-prefix/length | ipv6-addr | ipv6-prefix/length} [remote-as as-num[.as-num]
no neighbor {ip-addr | ip-prefix/length | ipv6-addr | ipv6-prefix/length} [remote-as as-num[.as-num]
Syntax Description
Command Default
This command has no default settings.
Command Modes
Neighbor address-family configuration
Router bgp configurationSupported User Rolesnetwork-admin
vdc-adminCommand History
Usage Guidelines
Use the neighbor command to enter the BGP neighbor configuration mode. When you enter the neighbor command, the prompt changes to switch(config-router-neighbor)#.
From the BGP neighbor configuration mode, you can perform the following actions:
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address-family—Configure an address-family (router, neighbor, vrf). See the address-family (BGP) command for information.
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This command is required only when the neighbor ebgp-multihop command is configured with a TTL value of 1. The address of the single-hop eBGP peer must be reachable. The neighbor update-source command must be configured to allow the BGP routing process to use the loopback interface for the peering session.
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To have the Cisco NX-OS software allow Border Gateway Protocol (BGP) sessions to use any operational interface for TCP connections, use the update-source command in router configuration mode. To restore the interface assignment to the closest interface, which is called the best local address, use the no form of this command.
If you specify a BGP peer group by using the peer-group-name argument, all the members of the peer group will inherit the characteristic configured with this command.
The update-source command must be used to enable IPv6 link-local peering for internal or external BGP sessions.
Examples
In the following example, a single-hop eBGP peering session is configured between two BGP peers that are reachable on the same network segment through a local loopback interfaces on each router:
BGP Peer 1
switch(config)# interface loopback 1switch(config-if)# ip address 10.0.0.100 255.255.255switch(config-if)# exitswitch(config)# router bgp 64512switch(config-router)# neighbor 192.168.0.200 remote-as 65534switch(config-router)# neighbor 192.168.0.200 ebgp-multihop 1switch(config-router)# neighbor 192.168.0.200 update-source loopback 2switch(config-router)# neighbor 192.168.0.200 disable-connected-checkswitch(config-router)#BGP Peer 2
switch(config)# interface loopback 2switch(config-if)# ip address 192.168.0.200 255.255.255switch(config-if)# exitswitch(config)# router bgp 65534switch(config-router)# neighbor 10.0.0.100 remote-as 64512switch(config-router)# neighbor 10.0.0.100 ebgp-multihop 1switch(config-router)# neighbor 10.0.0.100 update-source loopback 1switch(config-router)# neighbor 10.0.0.100 disable-connected-checkswitch(config-router)#The following example sources BGP TCP connections for the specified neighbor with the IP address of the loopback interface rather than the best local address:
switch(config)# router bgp 110switch(config-router)# network 172.16.0.0switch(config-router)# remote-as 110switch(config-router)# update-source Loopback0The following example sources IPv6 BGP TCP connections for the specified neighbor in autonomous system 110 with the global IPv6 address of loopback interface 0 and the specified neighbor in autonomous system 120 with the link-local IPv6 address of ethernet interface 0/0:
switch(config)# router bgp 110switch(config-router)# neighbor 3ffe::3 remote-as 110switch(config-router)# neighbor 3ffe::3 update-source Loopback0switch(config-router)# neighbor fe80::2 remote-as 120switch(config-router)# neighbor fe80::2 update-source FastEthernet 0/0switch(config-router)# address-family ipv6switch(config-router-af)# neighbor 3ffe::3 activateswitch(config-router-af)# neighbor fe80::2 activateswitch(config-router-af)#Related Commands
net
To configure an Intermediate System-to-Intermediate System (IS-IS) network entity (NET) for the routing process, use the net command in global configuration mode. To remove a NET, use the no form of this command.
net net
no net net
Syntax Description
net
NET network services access point (NSAP) name or address for the IS-IS routing process; see the "Usage Guidelines" section for additional information about valid values.
Command Default
The defaults are as follows:
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Command Modes
Router configuration
VRF configurationSupported User Rolesnetwork-admin
vdc-adminCommand History
Usage Guidelines
An IS (intermediate system) is identified by an address known as a network access point (NASAP). The NSAP is divided up into three parts as specified by ISO/AI 10589:
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A NET is an NSAP where the last byte is always the n-selector and is always zero. A NET can be from 8 to 20 bytes in length. The NET is formatted as follows: XX.AAAA.AAAA.AAAA[.AAAA].XX.
Under most circumstances, you should configure one NET only. It is possible to configure two or three NETs, but you should not configure more than one NET except for the following unusual circumstances:
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Configuring multiple NETs in these two circumstances can be temporarily useful because multiple area addresses enable you to renumber an area individually as needed.
If you are using IS-IS to perform IP routing only (no connectionless network service routing is enabled), you must configure a NET to define the router ID and area ID.
Examples
The following example shows how to configure a router with a NET which consists of the system ID 0000.0c11.1110 and area address 47.0004.0(1)04d.0001:
switch(config)# router isis firstcompanyswitch(config-router)# net 47.0004.0(1)04d.0001.00
Related Commands
network
To configure an IP prefix to advertise, use the network address family configuration mode command. To remove the IP prefix to advertise, use the no form of this command.
network ip-addr | ip-prefix/length mask mask-num [route-map name]
no network ip-network | ip-prefix/length mask mask-num [route-map name]
Syntax Description
Command Default
This command has no default settings.
Command Modes
Neighbor address-family configuration
Router bgp configurationSupported User Rolesnetwork-admin
vdc-adminCommand History
Usage Guidelines
IP prefix to advertise is considered for bestpath and advertisement to peers only if a route of equal or more specificity is present in the routing table.
Examples
The following example shows how to configure an IP prefix to advertise:
switch(config-router-af)# network 2.2.2.2 mask 3.3.3.3 route-map testswitch(config-router-af)#
