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Quick analysis of BSNL-Level3 bad routing issue

I can see BSNL having pretty high latency again with most of Europe again. It seems like they are using Level3 Communications AS 3356 along with Tata-VSNL for upstream. With Level3 transit BSNL has badly screwed up reverse path causing very high latency and awful bandwidth.

anurag@laptop:~$ ping server7 -c 5
PING server7.anuragbhatia.com (178.238.225.247) 56(84) bytes of data.
64 bytes from server7.anuragbhatia.com (178.238.225.247): icmp_req=1 ttl=52 time=320 ms
64 bytes from server7.anuragbhatia.com (178.238.225.247): icmp_req=2 ttl=52 time=320 ms
64 bytes from server7.anuragbhatia.com (178.238.225.247): icmp_req=3 ttl=52 time=319 ms
64 bytes from server7.anuragbhatia.com (178.238.225.247): icmp_req=4 ttl=52 time=327 ms
64 bytes from server7.anuragbhatia.com (178.238.225.247): icmp_req=5 ttl=52 time=320 ms
--- server7.anuragbhatia.com ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4004ms
rtt min/avg/max/mdev = 319.880/**321.765**/327.384/2.828 ms
anurag@laptop:~$

Expected latency values here should be around 150ms. A packet should not take more then 150ms round trip between Radaur, Haryana to Munich located server.

Some important life changes…

I am not with Cloudaccess.net anymore. It was very nice experience of setting up AS54456 from scratch along with design of anycasting DNS instances.  Wishing Cloudaccess.net good luck for time ahead.

I just started working with Packet Clearing House (PCH). Looking forward towards exciting time ahead! Interesting pages to checkout - Anycasting DNS for TLDs  & Peering information. 

Thanks for reading.

Boring exam days, anyways time for a quick blog post to keep taste in life. :)

One of my good friend informed me about eNom DNS servers failing randomly. He gave clothdiaperrevival.com as sample domain name for testing.

Quick Check from my home connection:

anurag@laptop ~ $ dig clothdiaperrevival.com a @dns1.name-services.com +short  
216.239.32.21  
216.239.34.21  
216.239.36.21  
216.239.38.21

anurag@laptop ~ $ dig clothdiaperrevival.com a @dns2.name-services.com +short  
216.239.36.21  
216.239.32.21  
216.239.38.21  
216.239.34.21

anurag@laptop ~ $ dig clothdiaperrevival.com a @dns3.name-services.com +short  
216.239.38.21  
216.239.34.21  
216.239.32.21  
216.239.36.21

anurag@laptop ~ $ dig clothdiaperrevival.com a @dns4.name-services.com +short  
216.239.32.21  
216.239.38.21  
216.239.34.21  
216.239.36.21

anurag@laptop ~ $ dig clothdiaperrevival.com a @dns5.name-services.com +short  
216.239.32.21  
216.239.34.21  
216.239.36.21  
216.239.38.21

Next, checking from my EU located server:

anurag@server7:~$ dig clothdiaperrevival.com a @dns1.name-services.com +short  
216.239.32.21  
216.239.34.21  
216.239.36.21  
216.239.38.21

anurag@server7:~$ dig clothdiaperrevival.com a @dns2.name-services.com +short

anurag@server7:~$ dig clothdiaperrevival.com a @dns3.name-services.com +short  
216.239.36.21  
216.239.38.21  
216.239.32.21  
216.239.34.21

anurag@server7:~$ dig clothdiaperrevival.com a @dns4.name-services.com +short  
216.239.32.21  
216.239.38.21  
216.239.36.21  
216.239.34.21

anurag@server7:~$ dig clothdiaperrevival.com a @dns5.name-services.com +short  
216.239.32.21  
216.239.34.21  
216.239.36.21  
216.239.38.21

dns2.name-services.com is failing when reached my EU based server.

Sleepless night. Reading more about Quagga and it’s options.

In meanwhile a quick 5min script to enable domain to BGP/IP/ASN mapping. This script is using basic dig command (for finding IP address) and Team Cymru whois service for IP to ASN/block mapping.

#!/bin/bash  
\# Script for domain name to IP/ASN/BGP block mapping  
hostname=v4.whois.cymru.com  
IP=$(dig $1 a +short)  
whois -h $hostname " -c -p $IP"

Yeah just 3 line script! Less code = more power! 

It has been an interesting week at village - dry weather, (ultra) dry classes, (boring) external seminars and more of depressing environment but one can always find some hope out of such depressing environment. Overall life here is colourful but one just needs to lookout for colours. :)   One interesting case to report today - F root server has quite bad connectivity in India. Last week a friend asked me for traceroutes to all root servers and here’s what I saw when I did traceroute for F root from BSNL connection: