Specifying the AS Path

By default, no AS path information is associated with static routes. To associate AS path information with IPv4 routes, include the as-path statement:

To associate AS path information with IPv6 routes, include the as-path statement:

For a list of hierarchy levels at which you can include these statements, see the statement summary sections for these statements.

as-path is the AS path to include with the route. It can include a combination of individual AS path numbers and AS sets. Enclose sets in brackets ( [ ] ). The first AS number in the path represents the AS immediately adjacent to the local AS. Each subsequent number represents an AS that is progressively farther from the local AS, heading toward the origin of the path.

Beginning with JUNOS Release 9.1, the range that you can configure for the AS number has been extended to provide BGP support for 4-byte AS numbers as defined in RFC 4893, BGP Support for Four-octet AS Number Space. You can now configure a number from 1 through 4,294,967,295. The JUNOS software continues to support 2-byte AS numbers.

You also can specify the AS path using the BGP origin attribute, which indicates the origin of the AS path information:

• igp—Path information originated within the local AS.
• egp—Path information originated in another AS.
• incomplete—Path information learned by some other means.

To attach the BGP ATOMIC_AGGREGATE path attribute to the static route, specify the atomic-aggregate statement. This path attribute indicates that the local system selected a less specific route rather than a more specific route.

To attach the BGP AGGREGATOR path attribute to the static route, specify the aggregator statement. When using this statement, you must specify the last AS number that formed the static route (encoded as two octets), followed by the IP address of the BGP system that formed the static route.

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