DNS delegation of mx.yahoo.com updated: May 20, 2013 4:55:56 PM
Delegation
step
query
auth
servers
1
mx.yahoo.com.
.
(f,e,j,d,l,k,g,c,i,b,a,h,m).root-servers.net.
2
mx.yahoo.com.
com.
(a,i,d,h,c,m,b,l,f,k,g,e,j).gtld-servers.net.
3
mx.yahoo.com.
yahoo.com.
(ns4,ns3,ns1,ns5,ns2).yahoo.com.
4
fd-fp3.wg1.b.yahoo.com.
yahoo.com.
(ns1,ns3,ns4,ns2,ns5).yahoo.com.
5
fd-fp3.wg1.b.yahoo.com.
wg1.b.yahoo.com.
(yf5,yf7,yf8,yf3,yf4,yf2,yf6,yf1).yahoo.com.
6
ds-fp3.wg1.b.yahoo.com.
wg1.b.yahoo.com.
(yf2,yf5,yf4,yf6,yf3,yf8,yf7,yf1).yahoo.com.
7
ds-eu-fp3-lfb.wa1.b.yahoo.com.
yahoo.com.
(ns4,ns2,ns1,ns3,ns5).yahoo.com.
8
ds-eu-fp3-lfb.wa1.b.yahoo.com.
wa1.b.yahoo.com.
(yf1,yf2).yahoo.com.
9
ds-eu-fp3.wa1.b.yahoo.com.
wa1.b.yahoo.com.
(yf2,yf1).yahoo.com.
We pick f.root-servers.net, one of the 13 root servers (1), and ask it about mx.yahoo.com and learn that com is delegated to 13 name servers (2), so we ask a.gtld-servers.net where we learn that yahoo.com is delegated to five name servers, including ns4.yahoo.com (3), so we ask that one where we see a CNAME from mx.yahoo.com to fd-fp3.wg1.b.yahoo.com, so we have to start all over again. We already know that ns1.yahoo.com is authoritative for yahoo.com (4) and ask it about fd-fp3.wg1.b.yahoo.com and learn that wg1.b.yahoo.com is delegated to eight name servers (5), so we ask yf5.yahoo.com and see a second CNAME from fd-fp3.wg1.b.yahoo.com to ds-fp3.wg1.b.yahoo.com. We start over for the third time and we already know that yf2.yahoo.com is authoritative for wg1.b.yahoo.com (6) and ask it about ds-fp3.wg1.b.yahoo.com and see yet another CNAME from ds-fp3.wg1.b.yahoo.com to ds-eu-fp3-lfb.wa1.b.yahoo.com. We have yet again to start all over and we already know that ns4.yahoo.com is authoritative for yahoo.com (7) and ask it about ds-eu-fp3-lfb.wa1.b.yahoo.com and learn that wa1.b.yahoo.com is delegated to two name servers (8), so we ask yf1.yahoo.com and see yet another CNAME from ds-eu-fp3-lfb.wa1.b.yahoo.com to ds-eu-fp3.wa1.b.yahoo.com. We have yet again to start all over and we already know that yf2.yahoo.com is authoritative for wa1.b.yahoo.com (9) and ask it about ds-eu-fp3.wa1.b.yahoo.com and get the following answer:
