[Contents] [Prev] [Next] [Index] [Report an Error]

Specifying the Peer’s AS Number

When configuring a peer, you must specify the peer system’s AS. To do this, include the peer-as statement:




peer-as autonomous-system;

For a list of hierarchy levels at which you can configure this statement, see the statement summary section for this statement.

For autonomous-system, you can specify a number of 1 through 4,294,967,295 in plain-number format. Beginning with JUNOS Release 9.1, the range for autonomous system (AS) numbers is extended to provide BGP support for 4-byte AS numbers as defined in RFC 4893, BGP Support for Four-octet AS Number Space. The JUNOS software continues to support 2-byte AS numbers.

Beginning with JUNOS Release 9.2, you can also configure a 4-byte AS number using the AS-dot notation format of two integer values joined by a period: <16-bit high-order value in decimal>.<16-bit low-order value in decimal>. For example, the 4-byte AS number of 65,546 in plain-number format is represented as 1.10 in the AS-dot notation format. You can specify a value in the range from 0.0 through 65535.65535 in AS-dot notation format.

For EBGP, the peer is in another AS, so the AS number you specify in the peer-as statement must be different from the local router’s AS number, which you specify in the autonomous-system statement. For IBGP, the peer is in the same AS, so the two AS numbers that you specify in the autonomous-system and peer-as statements must be the same. For more information about configuring the AS number of the local router, see Configuring the AS Number.

[Contents] [Prev] [Next] [Index] [Report an Error]