Robtex

Up: 81.23.64.0/19
Can't show all results, try to descend to a more specific CIDR
Down left: 81.23.64.0/21
Down right: 81.23.72.0/21
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
81.23.64.3	A	mail.addexpharma.net
81.23.64.3	A	mail.addexpharmaceuticals.ch
81.23.64.3	A	mail.addex-pharma.ch
81.23.64.76	A	largo.e-xpertsolution.com
81.23.64.76	A	xpsol.ch
81.23.64.76	A	e-xpertsolution.com
81.23.64.81	A+PTR	olrik.e-xpertsolutions.com
81.23.64.84	A	hulk.e-xpertsolutions.net
81.23.65.107	A	mail.deweckperren.ch
81.23.65.107	A	mail.dwpz.ch
81.23.65.130	A+PTR	mail.praxisgroup.ch
81.23.65.130	A	mail.nightingaletrustees.com
81.23.65.130	A	mail.ifmtrust.ch
81.23.65.148	A	exchsrv20.interacid-trading.ch
81.23.65.170	A	oyster-perpetual.cn
81.23.65.170	A	oyster-perpetual.com.cn
81.23.65.170	A	oyster-perpetual.com
81.23.66.12	PTR	gwmail01.syzgroup.com
81.23.66.12	A	gwmail01.oysterfunds.com
81.23.66.12	A	gwmail01.syzbank.net
81.23.67.4	A	mail.dalidemart.com
81.23.69.3	PTR	mailgateway01.dcie.ch
81.23.69.3	A	mail.dcie.ch
81.23.69.12	A	smtp.emcge.com
81.23.69.18	A	mailsrv.dcie.ch
81.23.69.84	PTR	smtp03.blombank.ch
81.23.69.84	A	mail.banorient.ch
81.23.69.87	A	mail.blombank.ch
81.23.69.91	A	smtp01.blombank.ch
81.23.69.117	A+PTR	smtp.pasche.ch
81.23.69.117	A	smtp.cmcic-banquepasche.li
81.23.69.117	A	smtp01.banquehavilland.ch
81.23.69.130	PTR	smtp02.pasche.ch
81.23.69.130	A	smtp02.cmcic-banquepasche.li
81.23.69.130	A	smtp02.agefor.com
81.23.69.147	A+PTR	exchsrv01.ekontrol.net
81.23.69.147	A	mail.ekontrol.net
81.23.69.189	A	linkproof2.safdie.com
81.23.70.11	A	datasrv01.massena.ch
81.23.70.35	A+PTR	mail.atlanticglobal.ch
81.23.71.4	PTR	datasrv01.ehbaumann.com
81.23.71.4	A	crystal-srv.ehbaumann.com
81.23.71.23	PTR	datasrv02.birs.ch
81.23.71.25	A	datasrv01.surcotec.ch
81.23.71.52	A+PTR	datasrv.besuchet.ch
81.23.71.52	A	besuchet.ch
81.23.71.52	A	mail.besuchet.ch
81.23.72.11	A	mail.verticaluk.net
81.23.72.19	A	datasrv01.cvpartners.ch
81.23.72.82	A	smtp01.cfe-finance.net
81.23.72.82	A	cas01.cfe-finance.com
81.23.72.91	PTR	datasrv.sef.ch
81.23.72.107	A+PTR	smtp.comisra.ch
81.23.72.108	A+PTR	smtp01.comisra.ch
81.23.72.109	A	mail.comisra.ch
81.23.72.115	A+PTR	datasrv01.cesaeng.ch
81.23.72.115	A	mail.cesaing.com
81.23.72.115	A	mx1.cesaeng.com
81.23.72.137	A+PTR	smtp01.mabank.ch
81.23.72.138	A	smtp02.mabank.ch
81.23.73.10	A	smtp01.irisnet.ch
81.23.73.22	A	cloudnetwork.ch
81.23.73.23	A	whatnamedesigns.com
81.23.73.24	A	barthelo.nl
81.23.73.24	A	rh-inter.net
81.23.73.37	PTR	exchcas01.intra.cybernetwork.ch
81.23.73.68	A+PTR	cobalt00.cybernetwork.ch
81.23.73.70	PTR	cobalt1.cybernetwork.ch
81.23.73.70	A	mail.tafelmacher-georges.com
81.23.73.70	A	www.onefortheroad.com
81.23.73.80	PTR	cobalt3.cybernetwork.ch
81.23.73.80	A	decaliaassetmanagement.com
81.23.73.80	A	mail.debiolley.com
81.23.73.85	PTR	cobalt4.cybernetwork.ch
81.23.73.90	PTR	ns2.cybernetwork.ch
81.23.73.104	A	smtp10.fbt.ch
81.23.73.110	PTR	smtp01.cybernetwork.ch
81.23.73.110	A	smtp01.cfe-finance.net
81.23.73.110	A	smtp01.fontaine.ch
81.23.73.111	PTR	smtp02.cybernetwork.ch
81.23.73.120	A+PTR	ns1.cybernetwork.ch
81.23.73.120	A	smtp02.regisseursduleman.ch
81.23.73.135	A+PTR	taragorne1.badid.com
81.23.73.135	A	a-81-23-73-135.assup.ch
81.23.73.135	A	mail.badid.com
81.23.73.171	PTR	exch09401.swissedge.com
81.23.73.171	A	mail.swissedge.com
81.23.73.211	PTR	exch10302.parismiki.ch
81.23.73.211	A	parismiki.ch
81.23.73.221	PTR	exch10602.scfid.ch
81.23.73.221	A	mail.scfid.ch
81.23.73.232	A+PTR	exch11001.aventro.net
81.23.73.232	A	mail.aventro.net
81.23.73.238	A+PTR	exch11301.ehbaumann.com
81.23.73.238	A	mail.ehbaumann.com
81.23.74.67	A+PTR	ns3.cybernetwork.ch
81.23.75.2	A	expertline.solutions