Bgp Path Selection Configuration - HP 4800G Series Configuration Manual

Attribute value : MED 0, localpref 100, pref-val 0, pre 255
State
Not advertised to any peers yet
# Display the BGP routing table on Switch D.
[SwitchD] display bgp routing-table
Total Number of Routes: 1
BGP Local router ID is 4.4.4.4
Status codes: * - valid, > - best, d - damped,
Network
*>i 9.1.1.0/24
[SwitchD] display bgp routing-table 9.1.1.0
BGP local router ID : 4.4.4.4
Local AS number : 65001
Paths: 1 available, 1 best
BGP routing table entry information of 9.1.1.0/24:
From
Relay Nexthop
Original nexthop: 10.1.3.1
AS-path
Origin
Attribute value : MED 0, localpref 100, pref-val 0, pre 255
State
Not advertised to any peers yet
The output information shows that:
Switch F can send route information to Switch B and Switch C through the confederation by
establishing only an eBGP connection with Switch A.
Switch B and Switch D are in the same confederation, but belong to different sub ASs. They obtain
external route information from Switch 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
In the figure below, all switches run BGP. Between Switch A and Switch B, and between Switch A
and Switch C are eBGP connections. Between Switch B and Switch D, and between Switch D and
Switch C are iBGP connections.
OSPF is the IGP protocol in AS 200.
Configure routing policies, making Switch D use the route 1.0.0.0/8 from Switch C as the optimal.
: valid, external-confed, best,
h - history, i - internal, s - suppressed, S - Stale
Origin : i - IGP, e - EGP, ? - incomplete
NextHop
10.1.3.1
: 10.1.3.1 (1.1.1.1)
: 0.0.0.0
: 100
: igp
: valid, internal, best,
MED LocPrf
0 100
1-58
PrefVal Path/Ogn
0 100i