DE-CIX operates so-called route server systems (see RFC7947 for a detailed description) to facilitate the exchange of BGP announcements between peers at DE-CIX. Each peer needs only to set up a BGP connection to the route server in order to receive the BGP announcements of all other peers with a BGP connection to the route server.
BGP session parameters
This section provides a brief overview of the BGP session parameters to connect to the route servers:
rs1
185.1.245.252 2001:7f8:df:0:3:1f77:a:1
rs2
185.1.245.253 2001:7f8:df:0:3:1f77:a:2
AS
204663
RIR macro (AS-SET)
IPv4: AS-DECIX-LEJ IPv6: AS-DECIX-LEJ-V6
Receive limit route server (our side):
IPv4: 40,000 IPv6: 20,000
Recommended prefix limit (your side):
IPv4: 250,000 IPv6: 90,000
BGP announcement filtering
This section describes the filtering mechanism that can be used to filter BGP announcements.
Your side
You can safely accept any BGP announcements received via the route servers as DE-CIX filters all incoming BGP announcements from all peers. he filtering mechanism is described below in the "DE-CIX side" section.
If you additionally want to filter on your side based on AS-SETs, you can do so by using one or more of the following AS-SETs registered in the RIPE database:
RIR macro (AS-SET)
Purpose
AS-DECIX-LEJ
AS-SETs of all DE-CIX LEJ customers (IPv4)
AS-DECIX-LEJ-V6
AS-SETs of all DE-CIX LEJ customers (IPv6)
AS-DECIX-LEJ-CONNECTED
ASNs of all DE-CIX LEJ customers
DE-CIX side
At DE-CIX, the route servers filter based on AS-path as well as IP prefixes. The BGP announcements that a route server receives from a peer are checked against the AS-SET the peer has provided. The AS-SET can be changed by contacting the DE-CIX Customer Service team.
How and what the route servers filters The DE-CIX filters are updated every 6 hours. Don't forget to register your IP prefixes in the IRR database well in advance (at least 24h before announcing the first time).
Bogon and Martian filtering Please make sure not to announce routes that
Check the status of your routes You can check the status of your announced routes to us in the DE-CIX Looking Glass – the reason why a route is filtered is also shown, as is a hint on how to fix the issue.
You can find more info on how to use the DE-CIX Looking Glass here.
IRR and RPKI validation Any routes you announce will also be RPKI (RFC6811, RFC7115) validated and checked against Internet Routing Registry (IRR) data. The AS-SET you provide to us will be recursively resolved. Then filtering is executed as follows:
The origin ASN needs to be in the customer cone (make sure that your AS-SET is well maintained and that all your downstreams are included)
If not, the route undergoes strict RPKI validation filtering (both origin and maxLength):
If the result is RPKI Valid, the route is accepted (a missing route object will have no implication in this case).
If the result is RPKI Invalid, the route is rejected.
If the result is RPKI NotFound/Unknown, we check if the route is resolvable for its origin ASN (this will be the case if a proper route object exists) and it might get accepted or rejected depending on the result.**
If it is, the route undergoes loose RPKI validation filtering (origin only):
If the result is RPKI Valid, the route is accepted.
if the result is RPKI Invalid, the route is rejected.
If the result is RPKI NotFound/Unknown, we check if the route is resolvable for its origin ASN (this will be the case if a proper route object exists) and it might get accepted or rejected depending on the result.**
**Loose filtering on IRRDB route objects We perform loose filtering on IRRDB route objects. For example: If you have a route object for 46.31.120.0/21, we will also accept e.g. 46.31.120.0/22 and other more specifics (up to /24 and up to /32 for blackholes). If this is not a desired behavior, we strongly encourage you to create a ROA and set the maxLength attribute accordingly. As RPKI validation is performed before the IRRDB route object check, it will render all undesired more specifics as RPKI Invalid, which will result in rejection of these. Please note that this method only works for non-blackholes as we perform loose RPKI validation on blackholes (i.e. ignore maxLength).
Route server setup
The route server setup at DE-CIX Leipzig consists of two machines. The software utilized to provide the route server service is BIRD. Only one of the two conventional route servers is required. However, in order to use the route server service, every peer is requested to connect to both machines for redundancy purposes, so that if one machine is out of order (e.g. maintenance), the route server service can still be used.
If the route servers system receive a BGP announcement marked as a blackhole, the NO-EXPORT community and the BLACKHOLE Community are added if these communities are not already present. This makes sure each BGP announcement marked 'Blackhole' can be easily filtered and does not spread widely in the Internet routing system.
Route server control
Operational BGP Communities can be used to control various functions of the route server. With these communities, you can:
control the redistribution of advertised prefixes,
prepend your own AS up to three times,
trigger the calculation of a new alternate path (if available) for your advertised prefixes before commencing any maintenance tasks.
Informational BGP communities are used to signal various information about redistributed prefixes. The DE-CIX route servers tag all prefixes with certain BGP communities to indicate their origin. You can use this information to determine where a certain prefix has been injected into the DE-CIX switching platform. This gives you the possibility to filter routes learned from the route servers based on geographical location.
We re-distribute all your announcements to other peers while honoring the BGP Communities which allow you to restrict your announcements
We advertise all announcements from other peers to you while honoring the BGP Communities which allow others peers to restrict their announcements
Monitor session
From an operational point of view, we advise setting up BGP sessions to both route servers, even if you do not want to peer with (i.e. advertise prefixes to) the route servers. This helps DE-CIX staff to quickly monitor the availability of each peer.
Please note that you are required to set up BGP sessions with (but don't need to advertise prefixes to) the DE-CIX route servers to be able to claim credits for the GlobePEER service. Otherwise DE-CIX may not be able to comply with its SLA (please see DE-CIX GlobePEER Technical Service Description - III. IP LAYER CONFIGURATION (ISO/OSI LAYER 3) - Interface configuration).
If your decision not to establish BGP sessions with the route servers was made due to your peering policy, please contact us to establish a monitoring-only session. You don’t have to advertise any prefixes and you won’t receive any prefixes from us during that session.
Sample configurations
The following section contains configuration examples for different router operating systems:
!
! Config example for Cisco IOS
! Peer and session templates, (S)AFI format and some basic filtering
! DE-CIX route servers rs1, rs2
! Your example ASN: 64500 (replace with your real ASN)
! Local preference route servers: 125
!
router bgp 64500
bgp router-id <YOUR_ROUTER_ID>
! Requires all your sessions to reset to take effect (if not already enabled)
