R3303-HP 6600/HSR6600 Routers Layer 3 - IP Routing Configuration Guide

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To enable the comparison of MED of routes from confederation peers:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enter BGP view or BGP-VPN
instance view.
• Enter BGP view:
bgp as-number
• Enter BGP-VPN instance view:
a. bgp as-number
b. ipv4-family vpn-instance
vpn-instance-name
Use either method.
3. Enable the comparison of
MED of routes from
confederation peers.
bestroute med-confederation
Optional.
Not enabled by default.
Configuring the NEXT_HOP attribute
By default, when advertising routes to an IBGP peer or peer group, a BGP router does not set itself as the
next hop. However, to ensure a BGP peer can find the correct next hop in some cases, you need to
configure the router as the next hop for routes sent to the peer.
For example, as shown in Figure 70, R
outer A and Router B establish an EBGP neighbor relationship, and
Router B and Router C establish an IBGP neighbor relationship. When Router B advertises a network
learned from Router A to Router C, if Router C has no route to IP address 1.1.1.1/24, you need to configure
Router B to set itself as the next hop (3.1.1.1/24) for the route to be sent to Router C.
Figure 70 Next hop attribute configuration
If a BGP router has two peers on a common broadcast network, it does not set itself as the next hop for
routes sent to an EBGP peer by default. As shown in Figure 71, R
outer A and Router B establish an EBGP
neighbor relationship, and Router B and Router C establish an IBGP neighbor relationship. They are on
t h e s a m e b ro a d c a s t n e t w o r k 1.1.1. 0 / 24 . W h e n R o u t e r B sends EBGP routes to Router A, it does not set
itself as the next hop by default. However, you can configure Router B to set it as the next hop (1.1.1.2/24)
for routes sent to Router A by using the peer next-hop-local command as needed.
Figure 71 Next hop attribute configuration