Sh bgp: received & advertised routes

Question

Dear all:
In reference at the commands:
- sh bgp neighbor A.B.C.D
- sh bgp neighbor A.B.C.D received routes
- sh bgp neighbor A.B.C.D advertised-routes
For example:
ROUTER#sh bgp neighbor A.B.C.D
  Policy for incoming advertisements is PEERING-IN
  Policy for outgoing advertisements is PEERING-OUT
  1 accepted prefixes, 0 are bestpaths
  Cumulative no. of prefixes denied: 8974070. 
    No policy: 0, Failed RT match: 0
    By ORF policy: 0, By policy: 8974070
  Prefix advertised 77, suppressed 0, withdrawn 2
In output this command we have # Prefixes: 
1 accepted & 0 are bestpaths (after policy) 
advertised 77, suppressed 0, withdrawn 2 (after policy)
8974070 prefix are deny
But, when you execute the next command:
ROUTER#sh bgp neighbor A.B.C.D received routes 
Processed 503233 prefixes, 503233 paths
In output this command we have# Prefixes = 503233 
And when you execute the next command:
ROUTER#sh bgp neighbor A.B.C.D advertised-routes
Processed 73 prefixes, 73 paths
In output this command we have:
73 prefixes advertised at peer
The question is:
What's the different between  counter 8974070  and 503233 (prefix received before apply policy)?
What's the different between  counter 77 (or 75 = 77 - 2 withdrawn) and  73 (prefix advertised before apply policy)?
Exist only one command that help at see total prefix received/advertised (different a sh bgp neighbor A.B.C.D received routes) ?
Thanks.

Answer 1

Not really because OSPF does not advertise routes it sends LSAs to it's peers.
So you need to look at the OSPF database ie. -
"sh ip ospf database"
which will show you all the LSAs the router is aware of.
In terms of all the LSAs the router has received it will show all of those but it will also show you LSAs that were generated by the router itself although the advertising router IP will point to that being the case.
In terms of all the LSAs the router advertises again it depends on the area and how that has been configured.
So for example an ABR might well have external LSAs (which aren't tied to any area in the OSPF database) but that doesn't necessarily mean it is advertising them to peers within an area as it could have been configured not to.
So it gives you a good idea but you need to also work out a few things for yourself as well.
Jon