3com S7906E 설치 설명서

 

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The mtu command is not recommended. It affects only parameter negotiation, which may occur; it 

does not affect data forwarding. 

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With Kompella MPLS L2VPN, you must create on the PE an L2VPN instance for each VPN where 

a directly connected CE resides. When creating an L2VPN, you must specify an encapsulation 

type matching that of the CE side interface. 

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The configuration of the VPN targets and RD are the same as that for MPLS L3VPN. For Kompella 

MPLS L2VPN, the RD is required. Once configured, an RD cannot be changed, unless you delete 

the L2VPN and then re-create it. 

 

CE ID is used for identifying a CE uniquely in a VPN. To facilitate the configuration, it is recommended to 

encode the CE IDs in continuous natural numbers starting from 1. 

The CE range of a VPN indicates the maximum number of CEs that can be connected to the VPN. You 

can configure a CE range greater than what is required based on your estimate of the future VPN 

expansion if the label resources are abundant (they are usually abundant). This can reduce the 

configuration modification required when CEs are added in the VPN in future. 

When creating a CE connection, if you do not specify the CE offset, the following are true: 

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For the first connection of the CE, the CE offset is the value specified by the default-offset 

parameter in the ce command. 

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For any other connection of the CE, the CE offset is that of the former connection plus 1. 

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When planning a VPN, you are recommended to encode CE IDs in incremental sequence starting 

from 1. When configuring connections, you are recommended to adopt the sequence of the CE IDs, 

in which case you can omit the ce-offset portion from most of the required commands. This 

simplifies the configuration. 

Note that you can only increase the CE range. For example, if the original CE range is 10, you can 

increase it to 20, but cannot reduce it to 5. The only way to reduce the CE range is to delete the CE and 

re-create it. 

When you increase the CE range, for example, from 10 to 20, the system does not release the original 

label block and then re-apply for a new label block of the size of 20. Instead, the system applies for a 

supplementary label block of the size of 10. This ensures that the existing services will not be 

interrupted. 

Follow these steps to create a CE connection: 

Enter system view 

— 

Enter MPLS L2VPN view 

mpls l2vpn vpn-name 

— 

Create a CE for a VPN and 
enter MPLS L2VPN CE view 

ce ce-name [ id ce-id [ range 
ce-range ] [ default-offset 
ce-offset ] ] 

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