H3C Technologies H3C S5560 Series Switches - Manual (Page 299)

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{
The output shows two valid routes to destination 9.1.1.0/24. The route with next hop 3.1.1.1 is
marked with a greater-than sign (>), indicating it is the optimal route (because the ID of Switch
B is smaller). The route with next hop 3.1.2.1 is marked with an asterisk (*), indicating it is a
valid route, but not the optimal route.
{
By using the display ip routing-table command, you can find only one route to 9.1.1.0/24 with
next hop 3.1.1.1 and output interface VLAN-interface 200.
3. Configure loading balancing:
Because Switch A has two routes to reach AS 65009, configuring load balancing over the two
BGP routes on Switch A can improve link usage.
# Configure Switch A.
[SwitchA] bgp 65008
[SwitchA-bgp] address-family ipv4 unicast
[SwitchA-bgp-ipv4] balance 2
[SwitchA-bgp-ipv4] quit
[SwitchA-bgp] quit
Verifying the configuration
# Display the BGP routing table on Switch A.
[SwitchA] display bgp routing-table ipv4
Total number of routes: 3
BGP local router ID is 1.1.1.1
Status codes: * - valid, > - best, d - dampened, h - history,
s - suppressed, S - stale, i - internal, e - external
Origin: i - IGP, e - EGP, ? - incomplete
Network NextHop MED LocPrf PrefVal Path/Ogn
* > 8.1.1.0/24 8.1.1.1 0 32768 i
* >e 9.1.1.0/24 3.1.1.1 0 0 65009i
* >e 3.1.2.1 0 0 65009i
The output shows that the route 9.1.1.0/24 has two next hops, 3.1.1.1 and 3.1.2.1, both of which are
marked with a greater-than sign (>), indicating that they are the optimal routes.
The display ip routing-table command output shows two routes to 9.1.1.0/24. One has next hop 3.1.1.1
and output interface VLAN-interface 200, and the other has next hop 3.1.2.1 and output interface
VLAN-interface 300.
BGP community configuration example
Network requirements
As shown in Figure 67 , Switch B establishes EBGP connections with Switch A and Switch C. Configure
NO_EXPORT community attribute on Switch A to make routes from AS 10 not advertised by AS 20 to any
other AS.