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On weekend  I was looking at BGP Instability Report data. As usual (and unfortunately) BSNL tops that list. BSNL is the most unstable autonomous network in the world. In past, I have written previously about how AS9829 is the rotten IP backbone.

This isn’t a surprise since they keep on coming on top but I think it’s well worth a check on what exactly is causing that. So I looked into BGP tables updates published on Oregon route-views from 21st May to 27th May and pulled data specifically for AS9829. I see zero withdrawals which are very interesting. I thought there would be a lot of announcements & withdrawals as they switch transits to balance traffic. If I plot the data, I get following chart of withdrawals against timestamp. This consists of summarised view of every 15mins and taken from 653 routing update dumps. It seems not feasible to graph data for 653 dumps, so I picked top 300.

Update - 12 July 2022

While migrating this old post from Wordpress to Hugo I realise that many of old external linked images are not available at source anymore and that breaks many of the external photos references on the blog.

In my previous post, I shared how I am running redundant uplinks at home (in non-BGP based setup) with the primary link on RF and secondary on DOCSIS. One of my good friends asked me the reason for the sudden jump in DOCSIS-based players across India, especially in smaller cities.

I posted about the home network in multiple other posts in past. I recent time I switched from Microtik SXT Lite 5 to Power Beam PBE-M5-400. This gave me a jump from 16dbi to 25dbi which gives much sharper beam. I also got a harness & climbed BTS myself (after getting permission from the manager) this time to switch gear. I think I can do a better job than wasting time in finding guys from local WISPs to do it. :)   Also, Essel Group launched Siti broadband in my home area and they are using DOCSIS. The network is overall fine though initially faced many outages due to fibre cuts here & there. As of now, the connection is reasonably stable. I am paying 860Rs/month ~ $14 for 10Mbps uncapped link which gives me 10Mbps down and 1.5Mbps up. From a price point, it’s an excellent connection to have for redundancy reasons. Now as the connection is stable enough to explore auto-failover. For last few months I took both primary links as well as backup links to the router in the form of tagged VLANs and used to push specific traffic based on source IP (device at home) or destination IP/port combination using policy based routing.  

A few days some folks in internet community noticed Cloudflare AS13335 announcing F root server’s routes covering prefix 192.5.5.0/24.  

dig version.bind ch txt @f.root-servers.net pic.twitter.com/YLW7hqt170

— Tony Finch (@fanf) April 3, 2017

 

Above tweet shows that case is clearly not a mistake but rather some sort of arrangement between Cloudflare and ISC (which is responsible for F-root). There was another discussion on DNS-OARC mailing list here. From our bgp.he.net tool, one can analyse route propagation for F root’s AS3557.

A while back I posted about routing filter generation via bgpq3 for Cisco (ios and XR) and Juniper JunOS based routers. I have received a number of emails in last few months about automated filter generation for Mikrotik routeros. Since Mikrotik’s CCRs are getting quite popular across small to mid-sized ISPs. So this blog post is about ways for generating filter config for a given ASN via IRR. One can use such logic with some kind of remote login mechanism like rancid (look for mtlogin here). I tried building around bgpq3 but it seems more easy with another popular tool in the domain called IRR Power Tools. Once IRR Power Tools (IRRPT) is setup, it allows us to fetch prefixes based via Internet Routing Registries and also aggregates them.   So, for instance, let’s pick AS54456: