Nokia Network Voyager, Справочное руководство

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Voyager Reference Guide 337
3.
Click the Based on ASPATH Regular Expressions link.
4.
Enter
500
in the
I
MPORT
ID
edit box.
The import ID specifies the order in which the import lists are applied to
each route. For route filters based on AS path regular expressions the
range of values is from 1 to 511.
5.
Enter a regular expression that identifies a set of ASes that should be
matched with the route’s ASPATH sequence:
100|200
This sequence accepts all routes whose ASPATH sequence contains 100
or 200 or both.
6.
Select one of the origin options from the
O
RIGIN
drop-down window;
then click A
PPLY
.
These options detail the completeness of AS path information. An origin
of
IGP
indicates that an interior routing protocol-learned route was
learned from an interior routing protocol and is most likely complete. An
origin of
EGP indicates the route was learned from an exterior routing
protocol that does not support AS paths, and the path is most likely
incomplete. When the path information is incomplete, an origin of
INCOMPLETE
is used.
7.
Enter a new route filter. In this example we assume we want to filter all
routes that are strictly more specific than
10.0.0.0/8
. In other words, we
allow all routes whose prefix is not
10.0.0.0/8
excepting for
10.0.0.0/8
itself, but we exclude all routes that are more specific, such as
10.0.0.0/9
and
10.128.0.0/9
.
8.
To configure this filter, we add
10.0.0.0
in
N
EW
IP
PREFIX TO IMPORT
entry box, and
8
in
M
ASK LENGTH
entry box. Click A
PPLY
.
9.
Select
REFINES
in the
M
ATCH TYPE
pulldown menu. This specifies that
we want routes that are strictly more specific than
10.0.0.0/8
.
10.
Finally, click on
RESTRICT
in the
A
CTION
field. This specifies that we
want to discard the routes that match this prefix.
11.
Click A
PPLY
. The filter is fully configured.