3Com S7902E, Руководство по настройке

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Configuration Prerequisites
The configuration tasks described in this section are about CSPF of MPLS TE. They must be used in
conjunction with CSPF and the dynamic signal protocol (CR-LDP or RSVP-TE). Before performing
them, be aware of each configuration objective and its impact on your system.
Configuration Procedure
Tuning CR-LSP setup involves these tasks:
z
Configuring route pinning
z
Configuring administrative group and affinity attribute
z
Configuring CR-LSP reoptimization
Configuring route pinning
Route pinning cannot be used together with reoptimization or automatic bandwidth adjustment.
Follow these steps to configure route pinning:
To do… Use the command... Remarks
Enter system view
system-view
––
Enter MPLS TE tunnel interface
view
interface tunnel
tunnel-number
––
Enable route pinning
mpls te route-pinning
Required
Disabled by default
Submit current tunnel
configuration
mpls te commit
Required.
Configuring administrative group and affinity attribute
The affinity attribute of an MPLS TE tunnel identifies the properties of the links that the tunnel can use.
Together with the link administrative group, it decides which links the MPLS TE tunnel can use. This is
done by ANDing the 32-bit affinity attribute with the 32-bit link administrative group attribute. When
doing that, a 32-bit mask is used. The affinity bits corresponding to the 1s in the mask are “do care” bits
which must be considered while those corresponding to the 0s in the mask are “don’t care” bits.
For a link to be used by a TE tunnel, at least one considered affinity bit and its corresponding
administrative group bit must be set to 1.
Suppose the affinity of an MPLS TE tunnel is 0xFFFFFFFF and the mask is 0x0000FFFF. For a link to
be used by the tunnel, the leftmost 16 bits of its administrative group attribute can be 0s or 1s, but at
least one of the rest bits must be 1.
The affinity of an MPLS TE tunnel is configured at the first node on the tunnel and then signaled to the
rest nodes through RSVP-TE.
The associations between administrative groups and affinities may vary by vendor.