Poor performance of K-root server (Delhi node)
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 193.0.14.129: icmp_req=4 ttl=44 time=312 ms
64 bytes from 193.0.14.129: icmp_req=5 ttl=44 time=313 ms
--- 193.0.14.129 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4001ms
rtt min/avg/max/mdev = 309.687/312.019/313.333/1.289 ms
Quick NS lookup for .com zone:
dig @193.0.14.129 com.
; <<>> DiG 9.18.1-1ubuntu1.1-Ubuntu <<>> @193.0.14.129 com.
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 21791
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 13, ADDITIONAL: 27
;; WARNING: recursion requested but not available
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
;; QUESTION SECTION:
;com. IN A
;; AUTHORITY SECTION:
com. 172800 IN NS a.gtld-servers.net.
com. 172800 IN NS b.gtld-servers.net.
com. 172800 IN NS c.gtld-servers.net.
com. 172800 IN NS d.gtld-servers.net.
com. 172800 IN NS e.gtld-servers.net.
com. 172800 IN NS f.gtld-servers.net.
com. 172800 IN NS g.gtld-servers.net.
com. 172800 IN NS h.gtld-servers.net.
com. 172800 IN NS i.gtld-servers.net.
com. 172800 IN NS j.gtld-servers.net.
com. 172800 IN NS k.gtld-servers.net.
com. 172800 IN NS l.gtld-servers.net.
com. 172800 IN NS m.gtld-servers.net.
Looking at traceroute:
traceroute to k.root-servers.net. (193.0.14.129), 30 hops max, 60 byte packets
1 router.local (192.168.1.1) [AS8151/AS28513] 4.206 ms 5.041 ms 5.892 ms
2 117.212.40.1 (117.212.40.1) [AS9829] 32.243 ms 33.918 ms 36.122 ms
3 218.248.173.42 (218.248.173.42) [AS9829] 38.320 ms 42.492 ms 45.021 ms
4 203.190.136.17 (203.190.136.17) [AS9430] 337.645 ms 346.152 ms 346.837 ms
5 k.root-servers.net (193.0.14.129) [AS25152] 348.053 ms 349.664 ms 351.468 ms
Issue seems in connectivity between BSNL (AS9829) & AS9439 which belongs to Software Technology Parks Of India. Issue seems purely with BSNL and not with other major ISP’s like Bharti Airtel.
Checking K-root from Airtel Delhi node:
Tue Jan 10 16:34:48 GMT+05:30 2012
ping 193.0.14.129 Type escape sequence to abort. Sending 5,
100-byte ICMP Echos to 193.0.14.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms DEL-ISP-MPL-ACC-RTR-9#
Next, traceroute from Airtel Delhi PoP to K-root:
Tue Jan 10 16:39:00 GMT+05:30 2012
traceroute 193.0.14.129 Type escape sequence to abort.
Tracing the route to k.root-servers.net (193.0.14.129)
1 218.100.48.6 0 msec 4 msec 0 msec
2 k.root-servers.net (193.0.14.129) [AS 25152] 0 msec 0 msec 0 msec
DEL-ISP-MPL-ACC-RTR-9#
All seems pretty good for Airtel. :)
Summary:
BSNL (AS9829) was earlier routing traffic directly to K-root server’s via RIPE NCC - AS25152 but because of some changes it’s now using STPI and which seems to be having badly choked port in niXi. BSNL should be using route to 25152:4 (RS-KROOT-DELHI) directly to fix this but I wonder if BSNL Network admins read my blog posts. :(
Update:
author: “Anurag Bhatia” url: “/2012/01/dns/poor-performance-of-k-root-server-delhi-node/”
17th Jan 2011 Issue seems fixed by now. Routing now direct skilling STPI.