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Service feature

DE-CIX Looking Glass

With the DE-CIX looking glass service, it is possible to easily search for an AS number, a peer, or a particular IP prefix. In addition, the looking glass service provides information on why a certain route is rejected by the route server (e.g. due to IRR filters). Below you can find a detailed explanation of how to use the looking glass, how to narrow down search results, what exactly you can see, some typical search examples, and more information about query strings and how to use the API in your own scripts. 

The DE-CIX Looking Glass utilizes the open source projects Alice-LG and birdwatcher. A big thank you to all who contributed to these projects!

How to use the DE-CIX Looking Glass

There are two basic ways to get information:

  • The global search over all route servers (1)
  • The neighbor overview (2)

With the global search, you can search for IP prefixes, peer names, or ASNs. This is the fastest way if you need to get information about a specific network; you see immediately at which DE-CIX IXs it is available.

With the neighbor overview, you can have a look at a specific route server. It shows you which networks are available at a specific route server, provides BGP session information (state, last state changed), and gives you a summary of received/accepted/filtered routes from each peer.

DE-CIX Looking Glass search
The global search over all route servers (1) and the neighbor overview (2).

The global search over all route servers

With the global search, you can search across all DE-CIX route servers. You can directly search for:

  • Prefixes
  • Peers (by name, e.g. DE-CIX)
  • ASNs (by prefixing AS, e.g. AS51531)

Just type in what you're looking for.

DE-CIX Looking Glass global search
The global search function.

Narrow down the search results

On the results page, it is possible to narrow down the search results with three drop-down menus on the right. You can refine your search by:

  • Route server
  • Neighbor (in case your search matches more than one route server peer)
  • BGP Communities (multiple BGP Community values can be selected; the Communities are ordered by value)

The selected filters appear above the drop-down field and can be removed easily by clicking the red 'X' icon.

Please note: The database that is used to generate the search results in the global search contains data that may be up to 30 minutes old. The actual cache age is displayed in the upper right corner.

DE-CIX Looking Glass result filter
Narrow down the results of global search.

The neighbor overview

Using the neighbor overview, you can have a look at individual Ruhr-CIX route servers and their BGP peers (and their current status, e.g. session up, down, or errors).

To start the overview, select the DE-CIX IX first and choose a route server. This will result in a view that contains all peers that are known to the selected route server. All table columns are sortable in ascending or descending order, and data in this view is cached for approximately three minutes.

Narrow down the displayed data

With the search bar at the top, you can narrow down the data displayed. You can search for:

  • Neighbor IP
  • Peers (e.g. DE-CIX)
  • ASNs (e.g. 6695)
DE-CIX Looking Glass menu to choose route server
Menu to choose a route server for the neighbor overview.

Get information about a specific route server neighbor

You can see more information about a specific route server neighbor by clicking on its neighbor IP. Data in this view is cached for five minutes. All routes (filtered, accepted, and not exported) are shown. If the selected peer operates more than one router, you can switch between routers by clicking the tabs shown at the top. There are also quick links available to jump to sections with filtered, accepted, and not exported routes directly. Routes that are the best path are marked with a star icon. 

If a route is rejected, the reason is displayed in text below the affected route. You can hover over the text to get a detailed explanation of what went wrong and how to fix it. You can also click on the reject reason to explore the route in question in the IRR Explorer.  

DE-CIX Looking Glass specific route server neighbor
Information on a specific route server neighbor.

To get more detailed information about a route, just click on it. This will show you the BGP attributes:

  • Origin of the route (IGP/EGP/unknown)
  • Local Preference
  • BGP next-hop
  • MED
  • AS Path
  • BGP Standard, Extended and Large Communities in human-readable format if known by the route server (i.e. DE-CIX Action and Informational Communities and well-known BGP Communities)
DE-CIX Looking Glass detailed route information
Detailed route information with BGP attributes.

Typical search examples

Find out which prefixes are filtered on your session(s)

  • Enter your ASN in the global search field on the start page
  • A list of prefixes from your ASN on all route servers is shown
  • Filtered prefixes are shown at the top of the page (before accepted routes)
    • You can narrow down your search by using the drop-down menus on the right
    • You can click on the link in the description column to go the corresponding route server for the selected prefix

Find out which prefixes are blackholed by AS51531

  • Enter AS51531 in the global search field on the start page
  • A list of prefixes from AS51531 on all route servers is shown
  • Look for prefixes with a blackhole icon or narrow down your search by selecting '(65535:666) BLACKHOLE (RFC7999)' from the BGP Communities drop-down on the right
  • Now you see all prefixes blackholed by AS51531

Find out which networks peer with the route server in a particular metro

  • In the neighbor overview, select the DE-CIX IX and the primary route server (rs1) for the desired metro, e.g. select the primary route server in New York: rs1.NYC.de-cix.net (IPv4); participants usually peer with both route servers (rs1 and rs2) for both IPv4 and IPv6
  • If you want to search for a specific network, narrow down the data displayed with the search field on top or click directly on the name of the network in the table, then you will only see the router of this network; if the network has multiple connected routers, they appear as tabs above the table

Using query strings 

It is possible to use query strings in URLs, e.g. in bookmarks:

* Just replace rs1_fra_ipv4 with the corresponding RS

Use the API in your own scripts

Alice provides a JSON API for all DE-CIX route servers. You can use the API in your own scripts. The following endpoints are available:

Endpoint/example queryDescription
/api/v1/statusQuery the status of Alice
/api/v1/routeservers/rs1_fra_ipv4/statusQuery the status of route server rs1_fra_ipv4
/api/v1/routeservers/rs1_fra_ipv4/neighbors/R194_110/routes/receivedQuery route server rs1_fra_ipv4 for a list of received routes from peer R194_110 (80.81.194.110)
/api/v1/routeservers/rs1_fra_ipv4/neighbors/R194_110/routes/not-exportedQuery route server rs1_fra_ipv4 for a list of routes not exported to peer R194_110 (80.81.194.110)
/api/v1/routeservers/rs1_fra_ipv4/neighbors/R194_110/routes/filteredQuery route server rs1_fra_ipv4 for a list of filtered routes from peer R194_110 (80.81.194.110)
/api/v1/routeservers/rs1_fra_ipv4/neighbors/R194_110/routesQuery route server rs1_fra_ipv4 for a list of accepted routes from peer R194_110 (80.81.194.110)
/api/v1/routeservers/rs1_fra_ipv4/neighborsQuery route server rs1_fra_ipv4 for a list of its neighbors
/api/v1/routeserversQuery a list of route servers known to Alice
/api/v1/lookup/prefix?q=46.31.120.0/21Query Alice for prefix 46.31.120.0/21
/api/v1/configQuery the Alice configuration

If you have any questions, please feel free to contact us