Command Line Reference Guide

bgp recursive-bgp-next-hop
Enable next-hop resolution through other routes learned by BGP.
S5000
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
Command History
Version 9.0(1.3) Introduced on the S5000.
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.
The clear ip bgp command is required for this command to take effect and to keep the
BGP database consistent. 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.
S5000
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)
Command History
Version 9.0(1.3) Introduced on the S5000.
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.
BGP policies, containing regular expressions to match as-path and communities, tend to use a
lot of CPU processing time, which in turn affects the BGP routing convergence. Additionally,
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