How not to set up your DNS (part 1)
Presented in illustrations:
; dig +short ns harvest.idv.tw. harvest.idv.tw. www.harvest.idv.tw. ; dig +short a harvest.idv.tw. 188.8.131.52 ; dig +short a www.harvest.idv.tw. 184.108.40.206
To those setting up nameservers: when people said 'have two nameservers', they did not mean 'and feel free to give them the same IP address'.
As a bonus, harvest.idv.tw has probably doubled the amount of time many DNS servers take to give up on them when 220.127.116.11 is having a wee problem.