HP 5500 Ei 5500 Si Switch Series Configuration Guide

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Enabling MD5 authentication for TCP connections 
BGP employs TCP as the transport protocol. To increase security, configure BGP to perform MD5 
authentication when establishing a TCP connection. The two parties must have the same password 
configured to establish TCP connections.  
BGP MD5 authentication is not for BGP packets, but for TCP connections. If the authentication fails, no 
TCP connection can be established. 
To enable MD5 authentication for TCP connections: 
 
Step Command  Remarks 
1....

 223 
Configuring a large scale BGP network 
In a large-scale BGP network, configuration and maintenance become difficult because of the large 
numbers of BGP peers. To facilitate configuration, you can configure peer group, community, route 
reflector, or confederation as needed.  
Configuration prerequisites 
Peering nodes are accessible to each other at the network layer. 
Configuring BGP peer groups 
A peer group is a group of peers with the same route selection policy. 
In a large-scale network,...

 224 
Step Command 
1.  Enter system view. 
system-view 
2.  Enter BGP view. 
bgp as-number  
3.  Create an EBGP peer group. 
group group-name  external 
4.   Specify the AS number for the 
group.  peer group-name
 as-number  as-number  
5.  Add the peer into the group. 
peer ip-address  group  group-name   
 
 NOTE: 
•  Do not specify any AS number for a peer before adding it into the peer group.  
•   All of the added peers have the same AS number as that of the peer group.  
 
To configure an EBGP...

 225 
 NOTE: 
•  Do not specify any AS number for a peer before adding it into the peer group.  
•   Peers added in the group can have different AS numbers.  
 
Configuring BGP community 
A BGP community is a group of destinations with th e same characteristics. It has no geographical 
boundaries and is independent of ASs. 
You can configure a routing policy to define which destinations belong to a BGP community and then 
advertise the community attribute to a peer or peer group. 
You can apply a routing...

 226 
Step Command Remarks 
1.  Enter system view. 
system-view  N/A 
2.  Enter BGP view. 
bgp as-number   N/A 
3.  Configure the router as a route 
reflector and specify a peer or 
peer group as its client.  peer {
 group-name  | ip-address  } 
reflect-client  Not configured by default. 
4.
  Enable route reflection 
between clients.  reflect between-clients  Optional. 
Enabled by default. 
5.
  Configure the cluster ID of the 
route reflector.  reflector cluster-id
 cluster-id   Optional. 
By default,...

 227 
To configure confederation compatibility:  
Step Command  Remarks 
1.  Enter system view. 
system-view N/A 
2.  Enter BGP view. 
bgp as-number   N/A 
3.  Enable compatibility with routers not 
compliant with RFC 3065 in the 
confederation.  confederation nonstandard 
Optional. 
Not enabled by default.
 
 
Configuring BGP GR 
Perform the following configuration on the GR Restarter and GR Helper. 
Follow these guidelines when you configure BGP GR: 
•
  A device can act as a GR Restarter and GR Helper...

 228 
Enabling logging of peer state changes 
 
Step Command Remarks 
1.  Enter system view. 
system-view  N/A 
2.  Enter BGP view. 
bgp as-number  N/A 
3.  Enable the logging of peer 
state changes globally.  log-peer-change  Optional. 
Enabled by default. 
4.
  Enable the logging of peer 
state changes for a peer or 
peer group.  peer {
 group-name  | ip-address  } 
log-change  Optional. 
Enabled by default. 
 
Configuring BFD for BGP 
BGP maintains neighbor relationships based on the ke
epalive timer...

 229 
Task Command Remarks 
Display advertised BGP routing 
information. display bgp
 network  [ | { begin  | exclude |  include } 
regular-expression  ]  Available in 
any view
 
Display AS path information.  display bgp paths [ 
as-regular-expression  | | { begin | 
exclude  | include  } regular-expression ]  Available in 
any view
 
Display BGP peer or peer group 
information.  display bgp peer 
[ ip-address  { log-info  | verbose  } | 
group-name  log-info  | verbose  ] [ | { begin  | exclude  
|...

 230 
Task Command Remarks 
Display BGP routing statistics. display bgp
 routing-table  statistic  [ | { begin | exclude  
|  include  } regular-expression  ]  Available in 
any view
 
Display the global router ID.  display router id 
[ | { begin | exclude  | include  } 
regular-expression  ]  Available in 
any view
 
 
Resetting BGP connections  
Task Command Remarks 
Reset all BGP connections.  reset bgp all Available in user 
view 
Reset the BGP connections to an AS. 
reset bgp as-number  Available in...

 231 
Figure 90 Network diagram 
 
 
Configuration procedure 
1. Configure IP addresses for inte rfaces. (Details not shown.) 
2. Configure IBGP: 
{  To prevent route flapping caused by port state  changes, this example uses loopback interfaces 
to establish IBGP connections.  
{  Because loopback interfaces are virtua l interfaces, you need to use the peer connect-interface 
command to specify the loopback interface as the source interface for establishing BGP 
connections.  
{  E n a b l e  OS P F  i n...