The Routing Over Large Clouds Mailing List Archive by date

[Curtis Villamizar <curtis@ans.net>]

In message <199503081911.OAA02946@maelstrom.acton.timeplex.com>, yakov@watson.i
bm.com writes:
> Bruce,
> 
> >I've seen proposed solutions for BGP4... and BGP4 is one of the most
> >difficult IP routing protocols to configure (at least here).
> 
> The following represents an example of a BGP4 configuration (provided
> by Paul Traina, cisco Systems):
> 
>     router bgp 109
>     neighbor 1.2.3.4 remote-as 5
> 
> I personally don't find this example to fit your description of BGP4
> as "one of the most difficult IP routing protocols to configure".
> 
> Granted that other, more complex BGP4 configuration are possible, but
> such configurations are nothing, but a reflection of complexities that
> exist in real networks.
> 
> The point is that complexity of BGP4 config always reflects the
> complexity of routing requirements imposed by domains -- for simple
> requirements the config is simple, for complex requirements the config
> is complex.
> 
> Yakov.


For gated this is:

	autonomoussystem 109;
	bgp yes {
		group type external peeras 5 {
			peer 1.2.3.4;
		};
	};

Doesn't look so bad either.

EBGP is an inter-AS routing protocol and typically inter-AS routing is
messy, but if the requirements are simple, the config is too.  For
IBGP, we simply list our IBGP peers.

	bgp yes {
		preference 105;
		group type routing      peeras 690
				proto slsp
				lcladdr 140.222.132.62
				setpref 105
				logupdown
		{
			peer 140.222.8.62;
			peer 140.222.11.62;
			peer 140.222.16.62;
		...
			peer 140.222.226.62;
			peer 140.222.230.62;
			peer 140.222.236.62;
			allow {
				140.222.0.62 mask 255.255.0.255;
			};
		};
	};

The "allow" lets us add a peer without changing any other configs
before doing a full config run.  This is an actual IBGP config which
lists 72 peers.  It has a few EBGP peers too.

Not terribly difficult either.

Curtis