Find duplicate IPs for different MACs

Using arp-scan to get a list of returned duplicate IP address. However, arp-scan will list duplicate IP with the same MAC address. I get a sorted output of asx.txt (shortened for brevity) ~~~ arp-scan 172.16.0.0/16 > as.txt sort as.txt > as2.txt cat as2.txt | uniq -D -w 36 > asx.txt kye-mgmt02:/data # cat asx.txt 172.16.150.68 d8:cb:8a:b0:6a:12 Micro-Star INTL CO., LTD. 172.16.150.68 d8:cb:8a:b0:6a:12 Micro-Star INTL CO., LTD. (DUP: 2) 172.16.150.69 00:23:24:9e:3d:32 G-PRO COMPUTER 172.16.150.69 00:23:24:9e:3d:32 G-PRO COMPUTER (DUP: 2) 172.16.150.70 00:23:24:9e:3d:82 G-PRO COMPUTER 172.16.150.70 00:23:24:9e:3d:82 G-PRO COMPUTER (DUP: 2) 172.16.150.71 d8:cb:8a:86:2f:56 Micro-Star INTL CO., LTD. 172.16.150.71 d8:cb:8a:86:2f:56 Micro-Star INTL CO., LTD. (DUP: 2) 172.16.150.72 d8:cb:8a:cf:f1:e8 Micro-Star INTL CO., LTD. 172.16.150.72 d8:cb:8a:cf:f1:e8 Micro-Star INTL CO., LTD. (DUP: 2) 172.16.150.73 d8:cb:8a:cf:f1:5d Micro-Star INTL CO., LTD. 172.16.150.73 d8:cb:8a:cf:f1:5d Micro-Star INTL CO., LTD. (DUP: 2) ~~~ So as you can see, all the IPs are really not duplicated because the IPs have the same MAC address to really find a duplicate IP with a different MAC, I edited the file and change the MAC of the last IP. ~~~ kye-mgmt02:/data # cat asx.txt 172.16.150.68 d8:cb:8a:b0:6a:12 Micro-Star INTL CO., LTD. 172.16.150.68 d8:cb:8a:b0:6a:12 Micro-Star INTL CO., LTD. (DUP: 2) 172.16.150.69 00:23:24:9e:3d:32 G-PRO COMPUTER 172.16.150.69 00:23:24:9e:3d:32 G-PRO COMPUTER (DUP: 2) 172.16.150.70 00:23:24:9e:3d:82 G-PRO COMPUTER 172.16.150.70 00:23:24:9e:3d:82 G-PRO COMPUTER (DUP: 2) 172.16.150.71 d8:cb:8a:86:2f:56 Micro-Star INTL CO., LTD. 172.16.150.71 d8:cb:8a:86:2f:56 Micro-Star INTL CO., LTD. (DUP: 2) 172.16.150.72 d8:cb:8a:cf:f1:e8 Micro-Star INTL CO., LTD. 172.16.150.72 d8:cb:8a:cf:f1:e8 Micro-Star INTL CO., LTD. (DUP: 2) 172.16.150.73 d8:cb:8a:cf:f1:5d Micro-Star INTL CO., LTD. 172.16.150.73 d8:cb:8a:cf:f1:55 Micro-Star INTL CO., LTD. (DUP: 2) ~~~ Looking on how to output the duplicate IPs with different MACs expected output ~~~ 172.16.150.73 d8:cb:8a:cf:f1:5d Micro-Star INTL CO., LTD. 172.16.150.73 d8:cb:8a:cf:f1:55 Micro-Star INTL CO., LTD. (DUP: 2) ~~~ I can't seem to find the right options to output the duplicate IPs with different MACs Help please. --- **tried cat asx.txt | uniq -D -s 15 -w 33 cat asx.txt | uniq -D -s 15 -w 17-33 cat asx.txt | uniq -D -f1 -w 33 cat asx.txt | uniq -D -f1 -w 32 cat asx.txt | uniq -D -f1 -w 31 cat asx.txt | uniq -D -f1 -w 30 cat asx.txt | uniq -D -f1 cat asx.txt | uniq -D -s 15 But none gives the desired output.