modification request for rs client feature
Inspired by discussion on "Announce less specific prefix in routeserver environment for upstream purpose (Message-ID: <4EEB4448.7070007@de-cix.net>) I would like to air the idea to modify the behaviour of BIRD as a route server. The idea of a route server is that it "... reduces modifications to advertised route attributes to be transparent (for example does not prepend its AS number to AS PATH attribute and keeps MED attribute)." However in case that there is a BGP speaker (gateway GW ) which is in the same ASN as the RS it is at least necessary to add the own ASN when announcing prefixes originating in the ASN. Hence I would like to propose to modify do not prepend own AS number to do not prepend owwn AS number except for prefixes learnt from iBGP Does that make sense? Best regards, Arnold -- Arnold Nipper / nIPper consulting, Sandhausen, Germany email: arnold@nipper.de phone: +49 6224 5593407 2 mobile: +49 152 53717690 fax: +49 6224 5593407 9
On Mon, Dec 19, 2011 at 10:08:52AM +0100, Arnold Nipper wrote:
Inspired by discussion on "Announce less specific prefix in routeserver environment for upstream purpose (Message-ID: <4EEB4448.7070007@de-cix.net>) I would like to air the idea to modify the behaviour of BIRD as a route server.
The idea of a route server is that it "... reduces modifications to advertised route attributes to be transparent (for example does not prepend its AS number to AS PATH attribute and keeps MED attribute)."
However in case that there is a BGP speaker (gateway GW ) which is in the same ASN as the RS it is at least necessary to add the own ASN when announcing prefixes originating in the ASN.
Hence I would like to propose to modify
do not prepend own AS number
to
do not prepend owwn AS number except for prefixes learnt from iBGP
Does that make sense?
Yes, it does make sense to me, because it is consistent with the current behavior on local (i.e. non-BGP) routes exported to BGP RS session. Note that there is a draft on RS behavior, which does not mention this: http://tools.ietf.org/html/draft-jasinska-ix-bgp-route-server-03 -- Elen sila lumenn' omentielvo Ondrej 'SanTiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."
on 22.12.2011 13:56 Ondrej Zajicek wrote:
On Mon, Dec 19, 2011 at 10:08:52AM +0100, Arnold Nipper wrote:
Inspired by discussion on "Announce less specific prefix in routeserver environment for upstream purpose (Message-ID: <4EEB4448.7070007@de-cix.net>) I would like to air the idea to modify the behaviour of BIRD as a route server.
The idea of a route server is that it "... reduces modifications to advertised route attributes to be transparent (for example does not prepend its AS number to AS PATH attribute and keeps MED attribute)."
However in case that there is a BGP speaker (gateway GW ) which is in the same ASN as the RS it is at least necessary to add the own ASN when announcing prefixes originating in the ASN.
Hence I would like to propose to modify
do not prepend own AS number
to
do not prepend owwn AS number except for prefixes learnt from iBGP
Does that make sense?
Yes, it does make sense to me, because it is consistent with the current behavior on local (i.e. non-BGP) routes exported to BGP RS session.
Changing the current behaviour would do no harm imho. Worst case is that you do prepend. Right?
Note that there is a draft on RS behavior, which does not mention this: http://tools.ietf.org/html/draft-jasinska-ix-bgp-route-server-03
I've dropped the authors a note. I'll update the list. Best regards, Arnold -- Arnold Nipper / nIPper consulting, Sandhausen, Germany email: arnold@nipper.de phone: +49 6224 5593407 2 mobile: +49 152 53717690 fax: +49 6224 5593407 9
On Dec 22, 2011, at 1:56 PM, Ondrej Zajicek wrote:
The idea of a route server is that it "... reduces modifications to advertised route attributes to be transparent (for example does not prepend its AS number to AS PATH attribute and keeps MED attribute)."
However in case that there is a BGP speaker (gateway GW ) which is in the same ASN as the RS it is at least necessary to add the own ASN when announcing prefixes originating in the ASN.
Hence I would like to propose to modify
do not prepend own AS number
to
do not prepend owwn AS number except for prefixes learnt from iBGP
Does that make sense?
Yes, it does make sense to me, because it is consistent with the current behavior on local (i.e. non-BGP) routes exported to BGP RS session.
Note that there is a draft on RS behavior, which does not mention this: http://tools.ietf.org/html/draft-jasinska-ix-bgp-route-server-03
but can it be optional, not required (eg: with some command to revert to old behavior) -j.
on 23.12.2011 01:08 robert jakub wrote:
On Dec 22, 2011, at 1:56 PM, Ondrej Zajicek wrote:
The idea of a route server is that it "... reduces modifications to advertised route attributes to be transparent (for example does not prepend its AS number to AS PATH attribute and keeps MED attribute)."
However in case that there is a BGP speaker (gateway GW ) which is in the same ASN as the RS it is at least necessary to add the own ASN when announcing prefixes originating in the ASN.
Hence I would like to propose to modify
do not prepend own AS number
to
do not prepend owwn AS number except for prefixes learnt from iBGP
Does that make sense?
Yes, it does make sense to me, because it is consistent with the current behavior on local (i.e. non-BGP) routes exported to BGP RS session.
Note that there is a draft on RS behavior, which does not mention this: http://tools.ietf.org/html/draft-jasinska-ix-bgp-route-server-03
but can it be optional, not required (eg: with some command to revert to old behavior)
I would propose to do it the other way round if the proposed behaviour would be implemented. I.e. make the old behaviour an option. Best regards, Arnold -- Arnold Nipper / nIPper consulting, Sandhausen, Germany email: arnold@nipper.de phone: +49 6224 5593407 2 mobile: +49 152 53717690 fax: +49 6224 5593407 9
participants (3)
-
Arnold Nipper -
Ondrej Zajicek -
robert jakub