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Usage
Information
In Non-Deterministic mode, paths are compared in the order in which they arrive. This method can lead
to the system choosing different best paths from a set of paths, depending on the order in which they
are received from the neighbors because MED may or may not get compared between adjacent paths.
In Deterministic mode (no bgp non-deterministic-med), the system compares MED between
adjacent paths within an AS group because all paths in the AS group are from the same AS.
When you change the path selection from Deterministic to Non-Deterministic mode, the path selection
for existing paths remains Deterministic until you enter the capture bgp-pdu max-buffer-size
command to clear existing paths.
bgp recursive-bgp-next-hop
Enable next-hop resolution through other routes learned by BGP.
Syntax
bgp recursive-bgp-next-hop
To disable next-hop resolution, use the no bgp recursive-bgp-next-hop command.
Defaults Enabled.
Command Modes ROUTER BGP
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
This command is a knob to disable BGP next-hop resolution using BGP learned routes. During the next-
hop resolution, only the first route that the next-hop resolves through is verified for the route’s protocol
source and is checked if the route is learned from BGP or not.
For this command to take effect and to keep the BGP database consistent, you need the clear ip
bgp command. Execute the clear ip bgp command right after executing this command.
Related
Commands
capture bgp-pdu max-buffer-size
bgp regex-eval-optz-disable
Disables the Regex Performance engine that optimizes complex regular expression with BGP.
Syntax
bgp regex-eval-optz-disable
To re-enable optimization engine, use the no bgp regex-eval-optz-disable command.
Defaults Enabled.
Command Modes ROUTER BGP (conf-router_bgp)
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
BGP uses regular expressions (regex) to filter route information. In particular, the use of regular
expressions to filter routes based on AS-PATHs and communities is quite common. In a large scale
configuration, filtering millions of routes based on regular expressions can be quite CPU intensive, as a
regular expression evaluation involves generation and evaluation of complex finite state machines.
612 IPv6 Border Gateway Protocol (IPv6 BGP)