Macintosh-7:~ trepex$ dig @a1.in.afilias-nst.in. dealco.in. NS   (output filtered)
dealco.in.      86400   IN   NS   ns2.dreamhost.com.
dealco.in.      86400   IN   NS   ns1.dreamhost.com.
dealco.in.      86400   IN   NS   ns3.dreamhost.com.

Macintosh-7:~ trepex$ dig @ns2.dreamhost.com. dealco.in NS
; <<>> DiG 9.7.6-P1 <<>> @ns2.dreamhost.com. dealco.in NS
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached

Macintosh-7:~ trepex$ dig @ns1.dreamhost.com. dealco.in NS
; <<>> DiG 9.7.6-P1 <<>> @ns1.dreamhost.com. dealco.in NS
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached

Macintosh-7:~ trepex$ dig @ns3.dreamhost.com. dealco.in NS
; <<>> DiG 9.7.6-P1 <<>> @ns3.dreamhost.com. dealco.in NS
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached

All nameserves for dealco.in are unreachable!

Just as I type this, the ns2 starts to respond again.