Summary
21.28.200.in-addr.arpa is a domain controlled by two nameservers on different IP networks.
cv.cl,
dcs.cl,
nic.cl,
alfa.cl,
ryk.com and at least 100 other hosts share nameservers with this domain.
28.200.in-addr.arpa is delegated to four nameservers, however three delegated nameservers are missing in the zone and one other nameserver is listed. There are three duplicated IP numbers. Some of them are on the same IP network.