nestat error (getnameinfo failed)

[root@a etc]# netstat -a > /test/a
getnameinfo failed
getnameinfo failed
getnameinfo failed
getnameinfo failed
getnameinfo failed

command is working fine (as i get output in file /test/a)

[root@a etc]# dig -x 10.xxx.xxx.xxx
; <<>> DiG 9.3.3rc2 <<>> -x 10.203.xxx.xxx
;; global options: printcmd
;; connection timed out; no servers could be reached

Anyone knows how to resolve this issue?