R2511-HP MSR Router Series Layer 3 - IP Routing Configuration Guide(V5)

235
Origin : igp
Attribute value : MED 0, localpref 100, pref-val 0, pre 255
State : valid, internal, best,
Not advertised to any peers yet
The output shows the following:
• Router F can send route information to Router B and Router C through the confederation by
establishing only an EBGP connection with Router A.
• Router B and Router D are in the same confederation, but belong to different sub ASs. They obtain
external route information from Router A and generate the same BGP route entries; it seems like that
they reside in the same AS although they have no direct connection in between.
BGP path selection configuration
Network requirements
As shown in Figure 69, all routers run BGP. EBGP runs between Router A and Router B, and between
Router A and Router C. IBGP runs between Router B and Router D, and between Router D and Router C.
OSPF is the IGP protocol in AS 200.
Configure routing policies to make Router D give priority to the route 1.0.0.0/8 learned from Router C.
Figure 69 Network diagram
Device Interface IP address Device Interface IP address
Router A Eth1/1 1.0.0.0/8 Router D S2/0 195.1.1.1/24
S2/0 192.1.1.1/24 S2/1 194.1.1.1/24
S2/1 193.1.1.1/24 Router C S2/0 195.1.1.2/24
Router B S2/0 192.1.1.2/24 S2/1 193.1.1.2/24
S2/1 194.1.1.2/24
Configuration procedure
1. Configure IP addresses for interfaces. (Details not shown.)
2. Configure OSPF on routers B, C, and D:
# Configure Router B.
<RouterB> system-view
[RouterB] ospf
[RouterB-ospf] area 0
[RouterB-ospf-1-area-0.0.0.0] network 192.1.1.0 0.0.0.255