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BGP Neighbor Configuration 命令(2)

4. neighbor {ip-address | peer-group-name} remove-private-as
 
Purpose: To remove private autonomous systems in updates to the neighbor or peer group. Private AS numbers are in the range 64512 to 65535. Private AS numbers should not be advertised to the Internet. The following conditions apply when using this command:
在到邻居或对等体组的更新中移除私有自治系统号. 私用AS号的范围是64512到65535. 私有AS号不能被通告到Internet. 当用这个命令时,需遵循以下条件:
 
Use only with EBGP peers.   仅仅用于EBGP对等体.
 If the update has only private AS numbers in the AS path, BGP removes them. 如果更新的AS路径中仅仅只有私有AS号的话,那么BGP将移除它.
If the AS path includes both private and public AS numbers, BGP doesn't remove the private AS numbers. This situation is considered a configuration error.   如果AS路径中私有和公有AS号都有的话,BGP将不会移除私有AS号. 这种形势被考虑成一个配置错误.
If the AS path contains the AS number of the EBGP neighbor, BGP doesn't remove the private AS number.   如果AS路径包括EBGP邻居的AS号,BGP将不会移除私有AS号.
If the AS path contains confederations, BGP removes the private AS numbers only if they come after the confederation portion of the AS path.
如果AS路径包括联盟,那么BGP仅仅当私有AS号跟在作为部分AS路径的联盟后面的话,才会被移除.


R1--------------R2----------------R3
AS65530       AS 1               AS 2
R1的路由通告,在R2 show ip bgp 表里 AS PATH是 65530 i ,在R3 show ip bgp 表里 AS PATH 是 1 65535 i . 在R2 BGP中配置 neighbor (IP address for R3) remove-private-as之后, 在R3 show ip bgp 表里 AS PATH 是 1 i .  

5. neighbor {ip-address | peer-group-name} soft-reconfiguration inbound
 
Purpose: If you have a policy configured with a BGP neighbor, such as a route map or distribute list, and you change the policy, the BGP session needs to be cleared in order for the new policy to take effect. When a BGP session is cleared, the cache is invalidated. This has a momentary impact on your routing. The **soft-reconfiguration** option allows you to change policies without clearing the BGP session. The two forms of soft reconfiguration are inbound and outbound. When you use inbound, soft reconfiguration updates from a neighbor are stored in memory, regardless of the inbound policy. Be aware that using inbound soft reconfiguration uses more memory than not using inbound soft reconfiguration. Outbound soft reconfiguration does not require additional memory and is always enabled.  

6. neighbor {ip-address | peer-group-name} unsuppress-map route-map-name
 
Purpose: When the **aggregate-address **command is used with the **summary-only** option, the more-specific routes of the aggregate are suppressed . The **aggregate-address summary-only** command suppresses the more-specific routes to all neighbors. You can use an unsuppress map to selectively leak more-specific routes to a particular neighbor.