11 Oct

i root server Mumbai node offline

Super dull time here. No classes going on due to “TCS Placement session” at college and this makes me to sit in my room most of time of my day. 

Yesterday I tested connectivity to all 13 Global Root DNS Servers and found i root was giving issue.

Here’s a my yesterday’s traceroute to i root: 

traceroute to i.root-servers.net. (, 30 hops max, 60 byte packets
1 router.local ( 1.470 ms 1.965 ms 2.452 ms
2 ( 26.030 ms 28.857 ms 31.243 ms
3 ( 34.673 ms 37.091 ms 41.025 ms
4 ( 72.853 ms 75.272 ms 77.959 ms
5 * * *
6 * * *


Since i root is another root server hosted within India by NIXI, I was quite sure this was issue again due to NIXI’s regional route enforcement policy along with missing transit link on i root. You can see my last blog post about same issue with F root here.

What was happening here was that Swedish provider Netnod had a anycasting node of i root server at NIXI Mumbai. Netnod uses IP from subnet announced by their AS 29216. In current setup Netnod router was connected to NIXI’s Mumbai subnet and was announcing that prefix. Thus all providers including BSNL were getting prefix in their routing table and hence there was a forward path from BSNL to Netnod Mumbai router.
But since ISPs like BSNL are forced to announce regional routes only, BSNL was NOT announcing their prefixes uses in Haryana at Mumbai (they do it at nearest regional exchange which is NIXI Noida) and thus Netnod router was not having any return path. This is true for many other big Indian providers who participate at more then one NIXI.


I informed Netnod Network Operation Center about the issue and they acted promptly by taking Mumbai anycasting instance down. As per their last email to me, they are keeping root server instance down unless they figure out what can be done to prevent this problem.

It is important to note here that if a node is taken down in anycasting that is fine since traffic is routed to other nearest node but keeping a faulty node damages.


Here’s my updated traceroute:

traceroute to (, 30 hops max, 60 byte packets
1 router.local ( 1.486 ms 1.965 ms 2.472 ms
2 ( 26.766 ms 30.029 ms 32.558 ms
3 ( 83.640 ms 83.920 ms 84.336 ms
4 ( 92.011 ms 92.447 ms 92.964 ms
5 ix-0-100.tcore2.MLV-Mumbai.as6453.net ( 85.625 ms 88.078 ms 90.528 ms
6 ( 227.061 ms 236.796 ms 237.210 ms
7 ( 238.669 ms 196.731 ms 197.479 ms
8 ( 205.832 ms 207.994 ms 210.133 ms
9 ( 204.067 ms 206.465 ms 208.859 ms
10 ( 211.274 ms 213.719 ms 216.668 ms
11 ( 223.069 ms 224.352 ms 225.494 ms
12 i.root-servers.net ( 227.769 ms 229.160 ms 231.765 ms


With this, India has lost I root server along with F root for time being unless Netnod is able to workout with NIXI on this. Good luck to last one i.e K root in Delhi to handle the load! 🙂

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