3.1.2 IP Configuration

Use this command to configure the IP basic settings, control IP interfaces, and IP routes. The maximum number of interfaces supported is 8, and the maximum number of routes is 32.

Command Syntax:

ip name-server [ <order> ] { <v_ipv4_ucast> | { <v_ipv6_ucast> [ interface vlan <v_vlan_id_static> ] | dhcp [ ipv4 | ipv6 ] [ interface vlan <v_vlan_id_dhcp> ] }
ip dns proxy

Table 3-2. Command Description
	Argument	Description
Parameter	`<order>`	Preference of DNS server. The default selection is 0.
	`<v_ipv4_ucast>`	A valid IPv4 unicast address
	`<v_ipv6_ucast>`	A valid IPv6 unicast address
	`dhcp`	Dynamic Host Configuration Protocol
Default	No DNS server configured
Mode	Global Configuration mode
Usage	Set the DNS for resolving domain names. To return to the default, use the 'no' version of the command. When the DNS proxy is required, use the command to enable the DNS proxy service.
Example	Example 1: DNS Server 0 setting is derived from any DHCPv4 VLANs-ID. `(config)# ip name-server 0 dhcp` Example 2: DNS Server 1 configured as a static IPv4 address. `(config)# ip name-server 1 192.168.0.10` Example 3: DNS Server 1 setting is derived from DHCPv4 VLANs-ID1. `(config)#ip name-server 1 dhcp ipv4 interface vlan 1`

Use this command to add IPv4, IPv6 interface.

Command Syntax:

ip address { { <address> <netmask> } | { dhcp [ fallback <fallback_address> <fallback_netmask> [ timeout <fallback_timeout> ] ] [ client-id { <port_type> <client_id_interface> | ascii <ascii_str> | hex <hex_str> } ] [ hostname <hostname> ] } }
ipv6 address <subnet>
ipv6 address { autoconfig | dhcp [ rapid-commit ] }

Table 3-3. Command Description
	Argument	Description
Parameter	`<address>`	IPv4 address
	`<netmask>`	IP netmask
	`dhcp`	Enable Dynamic Host Configuration Protocol
	`fallback`	DHCP fallback settings
	`client-id`	DHCP client identifier
	`hostname`	DHCP host name
	`<subnet>`	IPv6 prefix x:x::y/z
	`autoconfig`	Enable IPv6 Stateless Auto-configuration
	`rapid-commit`	Enable DHCPv6 client Rapid-Commit option
Default	N.A
Mode	VLAN Interface Configuration mode
Usage	Add VLAN interface and set all IPv4, IPv6 parameters. To disable the selected VLAN interface, use the ‘no’ version of the command. To remove it completely, use `no interface vlan <id>` from Global Configuration mode.
Example	Example 1: Set VLAN2 static IP address to 192.168.1.50 mask length 24. `(config)#interface vlan 2 (config-if-vlan)# ip address 192.168.1.50 255.255.255.0` Example 2: Add VLAN 3 and set it to get IP address from DHCP using MAC of port 1 as Client ID with a hostname "test". `(config)#interface vlan 3 (config-if-vlan)# ip address dhcp client-id GigabitEthernet 1/1 hostname test`

Use this command to add new IP route.

Command Syntax:

ip route <v_ipv4_addr> <v_ipv4_netmask> { <v_ipv4_gw> | blackhole } [ distance <v_distance> ]

Table 3-4. Command Description
	Argument	Description
Parameter	`<v_ipv4_addr>`	Network
	`<v_ipv4_netmask>`	Netmask
	`<v_ipv4_gw>`	Gateway
	`blackhole`	Create a blackhole route (all traffic to the network is discarded)
	`<v_distance>`	Distance value for this route
Default	N.A
Mode	Global Configuration mode
Usage	To route all unknown destination IPs to default gateway, use the following parameters: Network = 0.0.0.0, Netmask = 0.0.0.0, and Distance = 1. To remove the route, use `no ip route` command with all parameters for the selected route.
Example	Example 1: Add IP route to gateway 192.168.1.1. `(config)#ip route 0.0.0.0 0.0.0.0 192.168.1.1 1` Example 2: Remove IP route. `(config)#no ip route 0.0.0.0 0.0.0.0 192.168.1.1`