HP 5500 Ei 5500 Si Switch Series Configuration Guide

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[SwitchC-rip-1] quit 
[SwitchC] interface vlan-interface 200 
[SwitchC-Vlan-interface200] rip bfd enable 
[SwitchC-Vlan-interface200] quit 
# Configure Switch D.  
 system-view 
[SwitchD] rip 1 
[SwitchD-rip-1] network 192.168.3.0 
[SwitchD-rip-1] network 192.168.4.0 
3. Configure BFD parameters: 
# Configure Switch A. 
[SwitchA] bfd session init-mode active 
[SwitchA] interface vlan-interface 100 
[SwitchA-Vlan-interface100] bfd min-transmit-interval 500 
[SwitchA-Vlan-interface100] bfd...

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Summary Count : 2 
  Destination: 100.1.1.0/24 
     Protocol: RIP             Process ID: 1 
   Preference: 100                   Cost: 1 
 IpPrecedence:                    QosLcId: 
      NextHop: 192.168.1.2      Interface: vlan-interface 100 
    BkNextHop: 0.0.0.0         BkInterface: 
  RelyNextHop: 0.0.0.0          Neighbor : 192.168.1.2 
    Tunnel ID: 0x0                  Label: NULL 
  BKTunnel ID: 0x0                BKLabel: NULL 
        State: Active Adv             Age: 00h00m47s...

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  Destination: 100.1.1.0/24 
     Protocol: RIP             Process ID: 2 
   Preference: 100                   Cost: 2 
 IpPrecedence:                    QosLcId: 
      NextHop: 192.168.3.2      Interface: vlan-interface 300 
    BkNextHop: 0.0.0.0        BkInterface: 
  RelyNextHop: 0.0.0.0          Neighbor : 192.168.3.2 
    Tunnel ID: 0x0                  Label: NULL 
  BKTunnel ID: 0x0                BKLabel: NULL 
        State: Active Adv             Age: 00h18m40s 
          Tag: 0...

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Configuring OSPF 
Hardware compatibility 
The HP 5500 SI Switch Series does not support OSPF. 
Introduction to OSPF 
O p e n  S ho r tes t Pa t h  Fi rs t  ( OS P F)  i s  a  l i n k  s ta te  i nterior gateway protocol developed by the OSPF working 
group of the IETF. Now, OSPF version 2 (RFC 2328) is used. Unless otherwise noted, OSPF refers to 
OSPFv2 throughout this chapter. The term router in this chapter refers to both routers and Layer 3 
switches.  
OSPF has the following features: 
•   Wide...

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•  Each router uses the SPF algorithm to compute a shortest path tree showing the routes to the nodes 
in the AS. The router itself is the root of the tree. 
Router ID 
An OSPF process running on a router must have its own router ID. This ID is a 32-bit unsigned integer that 
uniquely identifies the router in the AS. 
OSPF packets 
OSPF uses the following types of packets: 
•  Hello —Periodically sent to find and maintain neighb ors, containing the values of some timers, 
information about the DR,...

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•  Neighbor —After startup, OSPF sends a hello packet on ea c h  OS P F  i n t e r f a c e.  A  ro u t e r  t h a t  re c e ive s  
the hello packet checks parameters in the packe t. If the parameters match its own, the router 
considers the sending router an OSPF neighbor. 
•   Adjacency —Two OSPF neighbors establish an adjacency relationship to synchronize their LSDBs. 
Therefore, any two neighbors without exchanging ro ute information do not establish an adjacency.   
Area based OSPF network...

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In practice, the requirements may not be satisfied due to lack of physical links. OSPF virtual links can 
solve this problem. 
A virtual link is established between two ABRs through a non-backbone area and is configured on both 
ABRs to take effect. The non-backbone area is called a transit area. 
In the following figure, Area 2 has no direct physical link to the backbone area 0. You can configure a 
virtual link between the two ABRs to connect Area 2 to the backbone area. 
Figure 18  Virtual link...

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•  To configure an area as a totally stub area, the  stub c o m m a n d  mus t  b e  c o n fig u re d  o n  ro u te rs  i n  t he  
area, and the ABR of the area must be configured with the  stub [ no-summary  ] command. 
•   A totally stub area cannot have an ASBR because AS  external routes cannot be distributed into the 
stub area. 
•   Virtual links cannot transit totally stub areas. 
NSSA area 
Similar to a stub area, an NSSA area does not impo rt AS external LSAs (Type-5 LSAs), but can import...

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•  An NSSA area can import external routes in Type 7 LSAs through the ASBR, but a stub area cannot.   
•   A totally NSSA area cannot import inter-area routes but an NSSA area can.  
Router types 
Router classification 
The following are OSPF router types and their positions in the AS: 
•  Internal router —All interfaces on an internal router belong to one OSPF area. 
•   Area Border Router (ABR) —An ABR belongs to more than two areas, one of which must be the 
backbone area. It connects the...

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The intra-area and inter-area routes describe the network topology of the AS. The external routes describe 
routes to external ASs.  
OSPF classifies external routes as Type -1 or Type -2.  A Type-1 external route has high credibility. The cost 
from a router to the destination of the Type-1 external route = the cost from the router to the corresponding 
ASBR + the cost from the ASBR to the destination of the external route. 
A Type-2 external route has low credibility, so OSPF considers the cost...