Magic Banana is on the right track, but we're not getting the hoped-for
output.
Here's the original data, without the third column (which was only presented
to indicate of the magnitude of the issue, which is that duplicated hostnames
are used to obfuscate their IPv4 addresses):
hostname IPv4 address
,,
alneo.ru 188.120.236.138
alnikino.ru 212.109.192.55
alnikino.ru 212.109.197.49
alnitcorp.fvds.ru 91.240.86.50
alod.fvds.ru 82.146.42.228
aloe-slings.com 62.109.12.147
alohomora.ru 82.146.60.203
alolika.su 82.202.160.112
alolika.su 92.63.110.215
aloshop.ru 62.109.17.21
alosvlad.fvds.ru 82.146.34.229
alovera.ru 212.109.193.28
The hoped-for output should be:
duplicated hostnames IPv4 address
alnikino.ru 212.109.192.55
alnikino.ru 212.109.197.49
alolika.su 82.202.160.112
alolika.su 92.63.110.215
Yes, the first column was already sorted; and the second column is free from
duplicate IPv4 addresses (which originally got in there because I
accidentally scanned some of the same IPv4 addresses more than once by
covering the same CIDR ranges with /24 that has already been covered with
larger CIDR spans).
Attached is a longer selection which includes hostnames that begin with
numerals, followed by the "redacted" version, containing only duplicated
hostnames and their IPv4 addresses (not yet rid of their enclosing
parentheses, artifacts of the nMap output files. My "redaction" is manual, of
course.
There's no need to retain the headers, of course; we are unlikely to get the
two columns confused; on the other hand, it is essential that the sorting
process correctly mantain the pairs from each row of the table.
I started to process the ~80,000 row ODS file and got through marking about
11,000 rows with 0's and 1's in about half a day's efforts. The race between
geek & grunt has begun !
