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Just finished with SANOG 26 conference and tutorials. It went very nice. Interestingly this time conference did not start early morning like it did in SANOG 24 at Noida. It was rather late in afternoon. Also, on very good note - there were less Govt. bureaucrats to bore attendees with usual stuff they always talk about but have very little idea. One specific interesting presentation was  Opportunities and Challenges for Broadband Wireless in India by Prof Abhay Karandikar (from IIT Mumbai). In start I felt it to be usual crappy 5G talk but later realized it was much more interesting. I loved the idea “Have 2Mbps everywhere static broadband and not some absurd number on mobile wireless broadband as we hear in case of 3G/4G. Although 2Mbps now is much slower and I would rather suggest that we target for 10Mbps everywhere (something which can be supported by copper/coax/fiber hybrid) but anyways it was nice refreshing talk. His thoughts were interesting but mostly impractical since had high dependence on useless project like NOFN. For the next part, we had a nice theme of keeping network simple which everyone kind of liked. Simplicity in Network Design & Deployments by Dany Pinto (from Colt) and Unified Forwarding with Segment Routing by Mohan Nanduri (from Microsoft Azure Cloud WAN team) were part of that. Santanu Dasgupta gave a presentation about Challenges of L2NID based Metro-E Architecture for vCPE/NFV Deployments and kind of confused everyone. :P

One of very cool features of IPv6 is link-local address which stays local to a given link. For this fe80::/10 is reserved. A /10 is a huge amount of address space in IPv6 (and in IPv4 too :) ). This means from fe80:0000:0000:0000:0000:0000:0000:0000 to febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff.

Since by design link-local address stays local, the address configured on the upstream/gateway router can be kept same for ease of use and comfort. This wasn’t the case of IPv4 where each VLAN/layer 2 domain had it’s own gateway.   So e.g if you have two VLANs or interfaces say: Gi1/0 and Gi2/0. You decide to use 10.100.100.0/30 on Gi1/0 and 10.100.100.4/30 on Gi2/0.

Out in Mumbai to attend SANOG 26.

Meet and greet if you are attending as well or around in Mumbai. :)

Came across this excellent presentation of Peter Hoose (Facebook). It gives a very good logical way of troubleshooting problems. Less about actual problems but about how Ops members companies like Facebook troubleshoot them.

This is from NANOG 64. Enjoy the presentation. :)

Few days back a friend of mine (who works for an ISP) congratulated me for joining HE. Along with wishes he told me that our bgp.he.net doesn’t works well and the reason he fealt so is because he couldn’t see all peers for his ASN in our tool.

This is not a problem and to be more broader - same applies on all popular tools other then bgp.he.net like RIPE Stats, Robtex AS analysis etc. The reason many of these tools do not and cannot show all peers is because they show what they see from the point of collection. E.g right now I am on BSNL (AS9829).

Just saw this excellent TED talk. Very inspiring. Points out many key problem in our way we (as Indians) work.  

Enjoy!

Some updates from personal life…

I have joined Fremont based IP backbone & colocation provider - Hurricane Electric and would be working on some cool things at AS6939. :)  

Updates on blog…

I have changed theme and entire look of blog and re-designed it with new plugins, more tweaking etc. As of now blog has more cleaner while theme which gives more space for posting, improved security with some ACLs, forced HTTPS to avoid telcos from injecting iframe in readers on 3G networks (which is very bad and worrying). Also, with use of bunch of plugins, now my I am hosting all static media content on AWS S3 to avoid local storage on server, it’s backup etc. Running it on AWS S3 with Geo replication + Cloudfront for CDN/efficient delivery made much more sense. Though sad that there’s no easy way for integration of Google Cloud storage with wordpress. S3 being more mature product makes it easier.

On one of key updates from my life - I have decided to exit from Spectranet AS10029. Overall it was fun working at Spectranet but the same time it was very different experience. I loved most of time I spent here and it was great learning experience.

Back on work to finish off my notice period!  

no router bgp 10029
delete local-as 10029

Just was looking around at EDNS support by Google. To find how it supports and how packet looks like I created a test NS records for dnstest.anuragbhatia.com pointing to one of test server (178.238.225.247). I wasn’t running any DNS server on the server. Just ran quick tcpdump.  

At server end:

sudo tcpdump 'port 53 and dst 178.238.225.247' -nn -vvv -w sample.pcap

Then I forcefully triggered DNS queries via Google’s recursor using:**

Came across excellent tool called “bgpq3” from one of recent posts in NANOG mailing list. This tool can general filters for a given ASN for Cisco or Juniper based on RADB’s data.

E.g Juniper style config for AS54456 (1st ASN on which I worked on!) :)

anurag@server7 ~> bgpq3 -Jl Cloudaccess as54456 
policy-options {
replace:
 prefix-list Cloudaccess {
    199.116.76.0/24;
    199.116.77.0/24;
    199.116.78.0/24;
    199.116.79.0/24;
 }
}
anurag@server7 ~> 

Cisco style config:

> anurag@server7:~$ bgpq3 -l Cloudaccess as54456 
no ip prefix-list Cloudaccess 
ip prefix-list Cloudaccess permit 199.116.76.0/24 
ip prefix-list Cloudaccess permit 199.116.77.0/24
ip prefix-list Cloudaccess permit 199.116.78.0/24
ip prefix-list Cloudaccess permit 199.116.79.0/24 
anurag@server7:~$

Cisco XR style config: