Robtex

Up: 212.15.0.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 212.15.0.0/23
Down right: 212.15.2.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
212.15.0.146	PTR	mail2.engingrup.com
212.15.0.146	PTR	mail2.yontemdisticaret.com.tr
212.15.0.146	PTR	mail2.yontemltd.com.tr
212.15.0.149	A+PTR	mail.enginsdh.net
212.15.0.149	A	evkiba.com
212.15.0.149	A	companyshoppg.com
212.15.1.3	PTR	mail.cerrahgil.com.tr
212.15.1.116	A	brckevmailbox.borcelik.com
212.15.1.131	PTR	mail.nbr.com.tr
212.15.1.163	A	tns-global.com.tr
212.15.1.163	A	ns1.piar.com.tr
212.15.1.163	A	www.piar.com.tr
212.15.1.164	A+PTR	mail.tns-global.com.tr
212.15.2.4	PTR	smtpgw.akb.org.tr
212.15.2.4	PTR	smtpgw.tspakb.org.tr
212.15.2.5	PTR	akin1.akintekstil.com.tr
212.15.2.44	A+PTR	sura.kuveytturk.com.tr
212.15.2.46	A	drcexpe.kuveytturk.com.tr
212.15.2.50	A+PTR	mail.burosit.com
212.15.2.50	PTR	mail.enborek.com
212.15.2.50	PTR	mail.ermetal.com
212.15.2.51	PTR	mail.burosit.com
212.15.2.51	PTR	mail.enborek.com
212.15.2.51	PTR	mail.ermetal.com
212.15.2.60	PTR	mail.kontekinsaat.com.tr
212.15.2.66	PTR	mail.platofinans.com
212.15.2.66	PTR	mail.platofs.com
212.15.2.66	PTR	mail.platofinans.com.tr
212.15.2.68	PTR	platofinans.com
212.15.2.68	PTR	mail.platofinans.com
212.15.2.68	PTR	mail.platofs.com
212.15.2.118	PTR	mail.fabeks.com
212.15.2.118	PTR	mail.fabeks.eu
212.15.2.147	PTR	mail.atasunoptik.com.tr
212.15.2.147	PTR	mail2.atasunoptik.com.tr
212.15.2.195	PTR	mail.buka.com.tr
212.15.2.195	A	mail.bukabilgisayar.com
212.15.2.195	A	mail.bukatechnology.com
212.15.2.196	PTR	mail.buka.com.tr
212.15.2.197	PTR	mail.buka.com.tr