IPv4 and IPv6 routing configuration

NOTE:

The term router in this document refers to routers, access controllers, unified switches, and access controller modules.

Overview

Upon receiving a packet, a router determines the optimal route based on the destination address and forwards the packet to the next router in the path. When the packet reaches the last router, it then forwards the packet to the destination host. Routing provides the path information that guides the forwarding of packets.

A router selects optimal routes from the routing table, and sends them to the forwarding information base

(FIB) table to guide packet forwarding. Each router maintains a routing table and a FIB table.

Static routes are manually configured. If a network's topology is simple, you only need to configure static routes for the network to work properly. Static routes cannot adapt to network topology changes. If a fault or a topological change occurs in the network, the network administrator must modify the static routes manually.

For more information about routing table and static routing, see H3C WX Series Access Controllers Layer

3 Configuration Guide.

Displaying the IPv4 active route table

Select Network > IPv4 Routing from the navigation tree to enter the page shown in

Figure 145 .

Figure 145 IPv4 active route table

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Table 66 Field description

Field Description

Destination IP Address

Destination IP address and subnet mask of the IPv4 route.

Mask

Protocol Protocol that discovered the IPv4 route.

Preference

Next Hop

Interface

Preference value for the IPv4 route.

The smaller the number, the higher the preference.

Next hop IP address of the IPv4 route.

Outgoing interface of the IPv4 route. Packets destined for the specified network segment will be sent out the interface.

Creating an IPv4 static route

1.

2.

Select Network > IPv4 Routing from the navigation tree.

Click the Create tab to enter the IPv4 static route configuration page, as shown in Figure 146

.

Figure 146 Creating an IPv4 static route

3.

4.

Specify relevant information as described in Table 67

.

Click Apply.

Table 67 Configuration items

Item Description

Destination IP Address

Enter the destination host or network IP address, in dotted decimal notation.

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Item Description

Mask

Enter the mask of the destination IP address.

You can enter a mask length or a mask in dotted decimal notation.

Preference

Set a preference value for the static route. The smaller the number, the higher the preference.

For example, specifying the same preference for multiple static routes to the same destination enables load sharing on the routes, while specifying different preferences enables route backup.

Next Hop

Interface

Enter the next hop IP address, in dotted decimal notation.

Select the outgoing interface.

You can select any available Layer 3 interface, for example, a virtual interface, of the device. If you select NULL 0, the destination IP address is unreachable.

Displaying the IPv6 active route table

Select Network > IPv6 Routing from the navigation tree to enter the page shown in

Figure 147 .

Figure 147 IPv6 active route table

Table 68 Field description

Field Description

Destination IP Address

Destination IP address and prefix length of the IPv6 route.

Prefix Length

Protocol Protocol that discovered the IPv6 route.

Preference

Next Hop

Interface

Preference value for the IPv6 route.

The smaller the number, the higher the preference.

Next hop IP address of the IPv6 route.

Outgoing interface of the IPv6 route. Packets destined for the specified network segment will be sent out the interface.

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Creating an IPv6 static route

1.

2.

Select Network > IPv6 Routing from the navigation tree.

Click the Create tab to enter the IPv6 static route configuration page, as shown in

Figure 148

.

Figure 148 Creating an IPv6 static route

3.

4.

Specify relevant information as described in Table 69

.

Click Apply.

Table 69 Configuration items

Item Description

Destination IP Address

Enter the destination host or network IP address, in the X:X::X:X format. The 128-bit destination IPv6 address is a hexadecimal address with eight parts separated by colons (:). Each part is represented by a 4-digit hexadecimal integer.

Prefix Length

Preference

Next Hop

Enter the prefix length of the destination IPv6 address.

Set a preference value for the static route. The smaller the number, the higher the preference.

For example, specifying the same preference for multiple static routes to the same destination enables load sharing on the routes, while specifying different priorities for them enables route backup.

Enter the next hop address, in the same format as the destination IP address.

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Item Description

Interface

Select the outgoing interface.

You can select any available Layer 3 interface, for example, a virtual interface, of the device. If you select NULL 0, the destination IPv6 address is unreachable.

IPv4 static route configuration example

Network requirements

The IP addresses of devices are shown in Figure 149 . IPv4 static routes must be configured on Switch A,

Switch B and AC for Host A and Host B to communicate with each other.

Figure 149 Network diagram

Configuration outlines

1.

2.

3.

On Switch A, configure a default route with Switch B as the next hop.

On Switch B, configure one static route with Switch A as the next hop and the other with AC as the next hop.

On AC, configure a default route with Switch B as the next hop.

Configuration procedure

1.

2.

3.

Configure a default route with the next hop address 1.1.4.2 on Switch A.

Configure two static routes on Switch B: one with destination address 1.1.2.0/24 and next hop address 1.1.4.1, and the other with destination address 1.1.3.0/24 and next hop address

1.1.5.6.

Configure a default route on AC: a.

Select Network > IPv4 Routing from the navigation tree. b. c. d.

Click the Create tab to enter the IPv4 static route configuration page, as shown in Figure 150

.

Enter 0.0.0.0 for Destination IP Address, 0 for Mask, and 1.1.5.5 for Next Hop.

Click Apply.

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Figure 150 Configuring a default route

Verifying the configuration

1.

2.

Display the route table:

Enter the IPv4 route page of Switch A, Switch B, and AC, respectively, to verify that the newly configured static routes are displayed as active routes on the page.

Ping Host B from Host A (assuming both hosts run Windows XP):

C:\Documents and Settings\Administrator>ping 1.1.3.2

Pinging 1.1.3.2 with 32 bytes of data:

Reply from 1.1.3.2: bytes=32 time=1ms TTL=128

Reply from 1.1.3.2: bytes=32 time=1ms TTL=128

Reply from 1.1.3.2: bytes=32 time=1ms TTL=128

Reply from 1.1.3.2: bytes=32 time=1ms TTL=128

Ping statistics for 1.1.3.2:

Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Approximate round trip times in milli-seconds:

Minimum = 1ms, Maximum = 1ms, Average = 1ms

IPv6 static route configuration example

Network requirements

The IP addresses of devices are shown in

Figure 151 . IPv6 static routes must be configured on Switch A,

Switch B and AC for Host A and Host B to communicate with each other.

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Figure 151 Network diagram

Vlan-int200

4::2/64

Switch B

Vlan-int300

5::2/64

Vlan-int200

4::1/64

Vlan-int300

5::1/64

Host A

1::2/64

Vlan-int100

1::1/64

Switch A

Vlan-int500

3::1/64

AC AP

Host B

3::2/64

Configuration outlines

1.

2.

3.

On Switch A, configure a default route with Switch B as the next hop.

On Switch B, configure one static route with Switch A as the next hop and the other with AC as the next hop.

On AC, configure a default route with Switch B as the next hop.

Configuration procedure

1.

2.

3.

Configure a default route with the next hop address 4::2 on Switch A.

Configure two static routes on Switch B: one with destination address 1::/64 and next hop address 4::1, and the other with destination address 3::/64 and next hop address 5::1.

Configure a default route on AC: a.

Select Network > IPv6 Routing from the navigation tree. b. c. d.

Click the Create tab to enter the IPv6 static route configuration page, as shown in Figure 152

.

Enter :: for Destination IP Address, select 0 for Prefix Length, and enter 5::2 for Next Hop.

Click Apply.

Figure 152 Configuring a default route

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Verifying the configuration

1.

2.

Display the route table:

Enter the IPv6 route page of Switch A, Switch B, and AC, respectively, to verify that the newly configured static routes are displayed as active routes on the page.

Ping Host B from Switch A:

<SwitchA> system-view

[SwitchA] ping ipv6 3::2

PING 3::2 : 56 data bytes, press CTRL_C to break

Reply from 3::2

bytes=56 Sequence=1 hop limit=254 time = 63 ms

Reply from 3::2

bytes=56 Sequence=2 hop limit=254 time = 62 ms

Reply from 3::2

bytes=56 Sequence=3 hop limit=254 time = 62 ms

Reply from 3::2

bytes=56 Sequence=4 hop limit=254 time = 63 ms

Reply from 3::2

bytes=56 Sequence=5 hop limit=254 time = 63 ms

--- 3::2 ping statistics ---

5 packet(s) transmitted

5 packet(s) received

0.00% packet loss

round-trip min/avg/max = 62/62/63 ms

Configuration guidelines

When you configure a static route, follow these guidelines:

1.

If you do not specify the preference when you configure a static route, the default preference is used. Reconfiguration of the default preference applies only to newly created static routes.

Currently, the Web interface does not support configuration of the default preference.

2.

3.

When you configure a static route, the static route does not take effect if you specify the next hop address first and then configure it as the IP address of a local interface, such as an Ethernet interface and VLAN interface.

When specifying the output interface, note that:

If NULL 0 or a loopback interface is specified as the output interface, there is no need to configure the next hop address.

If a point-to-point interface is specified as the output interface, you do not need to specify the next hop or change the configuration after the peer address has changed. For example, a PPP interface obtains the peer's IP address through PPP negotiation, and therefore, you only need to specify it as the output interface.

If the output interface is an NBMA or P2MP interface, which supports point-to-multipoint networks, the IP address-to-link layer address mapping must be established. Therefore, H3C recommends that you specify the next hop IP address when you configure it as the output interface.

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If you want to specify a broadcast interface (such as an Ethernet interface, virtual template, or

VLAN interface) as the output interface, which may have multiple next hops, you must specify the next hop at the same time.

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