Tata Communications - NTT routing issue for Akamai

Anurag Bhatia
Interestingly routing issues didn’t spare one of top CDN provider - Akamai! So what’s wrong? (from my BSNL connection): PING akamai.com (61.213.189.49) 56(84) bytes of data. 64 bytes from 61.213.189.49: icmp_req=1 ttl=52 time=492 ms 64 bytes from 61.213.189.49: icmp_req=2 ttl=52 time=492 ms 64 bytes from 61.213.189.49: icmp_req=3 ttl=52 time=474 ms 64 bytes from 61.213.189.49: icmp_req=4 ttl=51 time=492 ms 64 bytes from 61.213.189.49: icmp_req=5 ttl=51 time=489 ms \--- akamai.com ping statistics --- 5 packets transmitted, 5 received, 0% packet loss, time 22236ms rtt min/avg/max/mdev = 474.

Understanding dot in the end of hostname

Anurag Bhatia
This is a very popular mistake admins make - it’s missing . i.e dot in the end of hostname. This causes serious problems (and lot of frustration!). E.g taking example of popular Google’s cname record ghs.google.com. As we know if one would like to use mail.domain.com., he has to point the CNAME record to “ghs.google.com”. Now here if one misses dot in the end of ghs.google.com. - it will give a real value like:

Poor performance of K-root server (Delhi node)

Anurag Bhatia
Seems like k-root servers are having issue again. This is not the first time BSNL is having such issues. Last year I reported issue with K root server (which was actually because of downtime at Delhi node). Here’s some data for today’s case: PING 193.0.14.129 (193.0.14.129) 56(84) bytes of data. 64 bytes from 193.0.14.129: icmp_req=1 ttl=44 time=309 ms 64 bytes from 193.0.14.129: icmp_req=2 ttl=44 time=312 ms 64 bytes from 193.0.14.129: icmp_req=3 ttl=44 time=312 ms 64 bytes from 193.

Finding IPv6 from IPv4 address of a host

Anurag Bhatia
One of my friend asked me an interesting question about relating IPv4 with IPv6. His question was: in dual stack setup, if we have IPv4 of a router/host, how can we find IPv6 associated with it? Well, as far as I know there’s no direct way to relate IPv4 with IPv6 but there’s a nice trick out. Say e.g we have Google Public DNS operating at IPv4 - 8.8.8.8. To find IPv6 address of same server (if it exists at all), we can lookup for reverse DNS to get hostname, anurag@laptop:~$ dig -x 8.

Thoughts on NKN - National Knowledge Network

Anurag Bhatia
You might have heard of NKN i.e National Knowledge Network by Govt. of India. Overall idea of NKN was to connect all educational institutions within country including all IIT’s, IIM’s, NIT’s and various govt. universities on fiber at 1Gbps speed. Though little late and crazy way of solving problem, but still NKN is nice effort from Mr Sam Pitroda. I was talking to a friend from IIT Delhi last week, and here’s his speedtest.