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RE: bgp soft-reconfig in? posted 10/23/2002
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Dave,

	I would assume that "old" route-refresh is soft-reconfiguration,
and that "new" route-refresh is dynamic route-refresh.  

I get the following output with 12.1(12) though:

Rack8R4#sh ip bgp nei 170.8.2.254 | in refresh
    Route refresh: advertised and received(new)

	There is no mention of "old" refresh in the output, and I cannot
find a reference on CCO to it.  I'll keep you posted if I find out any
more info though.


Brian McGahan, CCIE #8593
Director of Design and Implementation
brian@xxxxxxxxxxxxxxx

CyscoExpert Corporation
Internetwork Consulting & Training
Voice: 847.674.3392
Fax: 847.674.2625


> -----Original Message-----
> From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf
Of
> MADMAN
> Sent: Wednesday, October 23, 2002 2:52 PM
> To: Brian McGahan
> Cc: Liban.Mohamed@xxxxxxxxxxxxxxx; ccielab@xxxxxxxxxxxxxx;
> rich@xxxxxxxxxxxxxx
> Subject: Re: bgp soft-reconfig in?
> 
>   I take it the route-refresh is the new, (12.1) dynamic inbound soft
> reset which requires no new config.  (I was checking out the URL you
> provided:)  So I set up a very basic BGP connection to see if this was
> negociated, both routers are running 12.2xx but I'm not sure what this
> output is saying and can't find it on CCO:
> 
> C7206VXRB#sh ip bgp nei
> BGP neighbor is 172.28.64.11,  remote AS 10, external link
>   BGP version 4, remote router ID 172.28.64.11
>   BGP state = Established, up for 00:00:13
>   Last read 00:00:12, hold time is 180, keepalive interval is 60
seconds
>   Neighbor capabilities:
>     Route refresh: advertised and received(old & new)
> 
>   What is the "Route refresh: advertised and received(old & new)"?  I
> assume the routers have negociated that they are capable of dynamic
> reset, what is the old and new??
> 
>   Thanks
> 
>   Dave
> 
> 
> Brian McGahan wrote:
> >
> >         Soft-reconfig and route-refresh are two different
technologies.
> > They both accomplish pretty much the same thing, however they are
> > implemented differently.
> >
> >
http://www.cisco.com/en/US/products/sw/iosswrel/ps1831/products_configur
> > ation_guide_chapter09186a00800d97fc.html#xtocid9
> >
> >         Route-refresh is preferable over soft-reconfig, since there
is
> > no additional configuration required, and it does not require any
> > additional memory resources.  Soft-reconfig inbound can be dangerous
to
> > use on a production BGP router, since inbound updates must be first
> > cached, attributes applied, then flushed from memory.  This means
that
> > if your router is short on memory, it could crash.
> >
> >         For those of you with access to the Partner E-Learning
> > connection, check out this link on multiprotocol extensions for BGP.
It
> > gives a good overview of route-refresh and ORF.
> >
> > http://cisco.partnerelearning.com/pec/trnevtdtl.asp?EvtID=39137
> >
> > HTH
> >
> > Brian McGahan, CCIE #8593
> > Director of Design and Implementation
> > brian@xxxxxxxxxxxxxxx
> >
> > CyscoExpert Corporation
> > Internetwork Consulting & Training
> > Voice: 847.674.3392
> > Fax: 847.674.2625
> >
> > > -----Original Message-----
> > > From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On
Behalf
> > Of
> > > Liban.Mohamed@xxxxxxxxxxxxxxx
> > > Sent: Sunday, October 20, 2002 2:47 PM
> > > To: ccielab@xxxxxxxxxxxxxx; rich@xxxxxxxxxxxxxx
> > > Subject: RE: bgp soft-reconfig in?
> > >
> > > The dynamic inbound soft reset capability was added to
> > > Cisco's BGP support in Cisco IOS Software Release
> > > 12.0(6)T. BGP Soft Reset Enhancement is supported on
> > > most Cisco router platforms up through the Cisco 7500
> > > Series routers. Soft resets can be initiated without extra
> > > commands using only the clear ip bgp in command.
> > >
> > >
> > > Basically soft reconfiguration is to gracefully allow policies to
be
> > > configured and activated without "hardsetting" the bgp session.
There
> > > are
> > > two kinds. Outbound and inbound. For inbound, all recieved routes
are
> > > stored
> > > regardless of the fact whether they are accepted or denied. When
we
> > > clear
> > > bgp with soft in, the polices are applied on the stored received
path.
> > > When we do clear bgp soft out, all entries in bgp table are re-run
and
> > > new
> > > updates are generated to be sent out.
> > > syntax:
> > > 1. sh ip bgp neighbor <peer address> received-routes
> > > This displays all the received updates from neighbor
> > > 2. neighbor <address> soft-reconfiguration <in>
> > > This will start storing the received updates. So required for
INBOUND
> > > soft
> > > reconfig. Outbound reconfig does not need anything to be
configured.
> > >
> > >
> > >
> > >
> > > Thanks,
> > >
> > >
> > > Liban Mohamed
> > > IP Engineer
> > > Sprintlink Internet BackBone
> > > www.sprint.net
> > >
> > > -----Original Message-----
> > > From: rich [mailto:rich@xxxxxxxxxxxxxx]
> > > Sent: Sunday, October 20, 2002 2:56 PM
> > > To: ccielab
> > > Cc: rich
> > > Subject: bgp soft-reconfig in?
> > >
> > >
> > > Is it true, when the neighbors support;
> > >
> > > Neighbor capabilities: (taken from sho ip bgp neighbor)
> > >     Route refresh: advertised and received
> > >     Address family IPv4 Unicast: advertised and received
> > >
> > > that you don't need to use the neighbor x.x.x.x
soft-reconfiguration
> > > inbound command?  I have not used this command once.  After making
a
> > > change to my bgp I just do a clear ip bgp XX sof.
> > >
> > >
> > > Rich
> 
> --
> David Madland
> CCIE# 2016
> Sr. Network Engineer
> Qwest Communications
> 612-664-3367
> 
> "You don't make the poor richer by making the rich poorer." --Winston
> Churchill