Hosts File: What it is and how to use it.

According to Wikipedia, the computer file hosts is an operating system file that maps hostnames to IP addresses. It is a plain text file. Originally a file named HOSTS.TXT was manually maintained and made available via file sharing by Stanford Research Institute.

Basically, the Hosts serve to redirect local domains and block access to resources on the internet.

Locais

Operating System	Versions	Location
Unix, Unix-like, POSIX		/etc/hosts
Microsoft Windows	3.1	%WinDir%\HOSTS
Microsoft Windows	95, 98, ME	%WinDir%\hosts
Microsoft Windows	NT, 2000, XP, 2003, Vista, 2008, 7, 2012, 8, 10	%SystemRoot%\System32\drivers\etc\hosts
Windows Mobile, Windows Phone		Registry: HKEY_LOCAL_MACHINE\Comm\Tcpip\Hosts
Apple Macintosh	9 and earlier	Preferences or System folder
Apple Macintosh	Mac OS X 10.0–10.1.5	(Added through NetInfo or niload)
Apple Macintosh	Mac OS X 10.2 and newer	/etc/hosts (a symbolic link to /private/etc/hosts)
Novell NetWare		SYS:etc\hosts
OS/2 & eComStation		"bootdrive":\mptn\etc\
Symbian	Symbian OS 6.1–9.0	C:\system\data\hosts
Symbian	Symbian OS 9.1+	C:\private\10000882\hosts
MorphOS	NetStack	ENVARC:sys/net/hosts
AmigaOS	4	DEVS:Internet/hosts
AROS		ENVARC:AROSTCP/db/hosts
Android		/etc/hosts (a symbolic link to /system/etc/hosts)
iOS	iOS 2.0 and newer	/etc/hosts (a symbolic link to /private/etc/hosts)
TOPS-20		HOSTS.TXT
Plan 9		/lib/ndb/hosts
BeOS		/boot/beos/etc/hosts
Haiku		/boot/common/settings/network/hosts
OpenVMS	UCX	UCX$HOST
OpenVMS	TCPware	TCPIP$HOST
	3.7, 5	!Boot.Resources.!Internet.files.Hosts
RISC OS	later boot sequence	!Boot.Choices.Hardware.Disabled.Internet.Files.Hosts

Examples

Original Windows Hosts

# Copyright (c) 1993-2006 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
#      102.54.94.97     rhino.acme.com          # source server
#       38.25.63.10     x.acme.com              # x client host

# localhost name resolution is handle within DNS itself.
#       127.0.0.1       localhost
#       ::1             localhost

Hosts file blocking Adobe and Techsmish (Warning: if you use this file, some softwares may not work properly afterwards).

# Copyright (c) 1993-2009 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
#      102.54.94.97     rhino.acme.com          # source server
#       38.25.63.10     x.acme.com              # x client host

# localhost name resolution is handled within DNS itself.
#	127.0.0.1       localhost
#	::1             localhost

#Adobe Blocker
127.0.0.1 na1r.services.adobe.com 
127.0.0.1 hlrcv.stage.adobe.com 
127.0.0.1 lmlicenses.wip4.adobe.com 
127.0.0.1 lm.licenses.adobe.com 
127.0.0.1 activate.adobe.com 
127.0.0.1 practivate.adobe.com 

#Techsmith blocker
127.0.0.1 activation.cloud.techsmith.com
127.0.0.1 oscount.techsmith.com
127.0.0.1 updater.techsmith.com
127.0.0.1 camtasiatudi.techsmith.com
127.0.0.1 tsccloud.cloudapp.net
127.0.0.1 assets.cloud.techsmith.com

Unnecessarily large Hosts File blocking Ad serving sites.

# Copyright (c) 1993-2009 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
#      102.54.94.97     rhino.acme.com          # source server
#       38.25.63.10     x.acme.com              # x client host

# localhost name resolution is handled within DNS itself.
#	127.0.0.1       localhost
#	::1             localhost

#Adobe Blocker
127.0.0.1 na1r.services.adobe.com 
127.0.0.1 hlrcv.stage.adobe.com 
127.0.0.1 lmlicenses.wip4.adobe.com 
127.0.0.1 lm.licenses.adobe.com 
127.0.0.1 activate.adobe.com 
127.0.0.1 practivate.adobe.com 

#Techsmith blocker
127.0.0.1 activation.cloud.techsmith.com
127.0.0.1 oscount.techsmith.com
127.0.0.1 updater.techsmith.com
127.0.0.1 camtasiatudi.techsmith.com
127.0.0.1 tsccloud.cloudapp.net
127.0.0.1 assets.cloud.techsmith.com

# [Start of entries generated by MVPS HOSTS]
#
# [Misc A - Z]
0.0.0.0 fr.a2dfp.net
0.0.0.0 m.fr.a2dfp.net
0.0.0.0 mfr.a2dfp.net
0.0.0.0 ad.a8.net
0.0.0.0 asy.a8ww.net
0.0.0.0 static.a-ads.com
0.0.0.0 atlas.aamedia.ro
0.0.0.0 abcstats.com
0.0.0.0 ad4.abradio.cz
0.0.0.0 a.abv.bg
0.0.0.0 adserver.abv.bg
0.0.0.0 adv.abv.bg
0.0.0.0 bimg.abv.bg
0.0.0.0 ca.abv.bg
0.0.0.0 track.acclaimnetwork.com
0.0.0.0 accuserveadsystem.com
0.0.0.0 www.accuserveadsystem.com
0.0.0.0 achmedia.com
0.0.0.0 csh.actiondesk.com
0.0.0.0 ads.activepower.net
0.0.0.0 app.activetrail.com
0.0.0.0 stat.active24stats.nl #[Tracking.Cookie]
0.0.0.0 traffic.acwebconnecting.com
0.0.0.0 office.ad1.ru
0.0.0.0 cms.ad2click.nl
0.0.0.0 ad2games.com
0.0.0.0 ads.ad2games.com
0.0.0.0 content.ad20.net
0.0.0.0 core.ad20.net
0.0.0.0 banner.ad.nu
0.0.0.0 adadvisor.net
0.0.0.0 tag1.adaptiveads.com
0.0.0.0 www.adbanner.ro
0.0.0.0 wad.adbasket.net
0.0.0.0 ad.pop1.adbn.ru
0.0.0.0 ad.top1.adbn.ru
0.0.0.0 ad.rich1.adbn.ru
0.0.0.0 adbox.hu
0.0.0.0 james.adbutler.de #[Tracking.Cookie]
0.0.0.0 www.adbutler.de
0.0.0.0 tw1.adbutler.us
0.0.0.0 www.adchimp.com
0.0.0.0 static.adclick.lt
0.0.0.0 engine.adclick.lv
0.0.0.0 show.adclick.lv
0.0.0.0 static.adclick.lv
0.0.0.0 www.adclick.lv
0.0.0.0 ad-clix.com
0.0.0.0 www.ad-clix.com
0.0.0.0 servedby.adcombination.com
0.0.0.0 adcomplete.com
0.0.0.0 www.adcomplete.com
0.0.0.0 adcore.ru
0.0.0.0 pixel.adcrowd.com
0.0.0.0 ct1.addthis.com
0.0.0.0 static.uk.addynamo.com
0.0.0.0 www.adexit.com
0.0.0.0 s.adexpert.cz
0.0.0.0 static.adfclick1.com
0.0.0.0 222-33544_999.pub.adfirmative.com
0.0.0.0 c.adfirmative.com
0.0.0.0 www.adfirmative.com
0.0.0.0 adfocus.ru
0.0.0.0 adx.adform.net
0.0.0.0 dmp.adform.net
0.0.0.0 s1.adform.net
0.0.0.0 server.adform.net
0.0.0.0 track.adform.net
0.0.0.0 server.adformdsp.net
0.0.0.0 adforce.ru
0.0.0.0 adforati.com
0.0.0.0 ads.adfox.ru
0.0.0.0 gazeta.adfox.ru
0.0.0.0 p.adframesrc.com
0.0.0.0 s.adframesrc.com
0.0.0.0 media.adfrontiers.com
0.0.0.0 www.adgitize.com
0.0.0.0 code.ad-gbn.com
0.0.0.0 www.ad-groups.com #[Ban Man Pro Banner Code]
0.0.0.0 adhall.com
0.0.0.0 pool.adhese.be
0.0.0.0 adhitzads.com
0.0.0.0 ads.static.adhood.com
0.0.0.0 app.pubserver.adhood.com
0.0.0.0 app.winwords.adhood.com
0.0.0.0 ssl3.adhost.com
0.0.0.0 www2.adhost.com
0.0.0.0 adfarm1.adition.com
0.0.0.0 imagesrv.adition.com
0.0.0.0 ad.adition.net
0.0.0.0 hosting.adjug.com
0.0.0.0 tracking.adjug.com
0.0.0.0 aj.adjungle.com
0.0.0.0 rotator.hadj7.adjuggler.net
0.0.0.0 thewrap.rotator.hadj7.adjuggler.net
0.0.0.0 yorick.adjuggler.net
0.0.0.0 adsearch.adkontekst.pl
0.0.0.0 stat.adlabs.ru
0.0.0.0 d.tds.adlabs.ru
0.0.0.0 www.adlantis.jp
0.0.0.0 publicidad.adlead.com
0.0.0.0 www.adlimg03.com
0.0.0.0 regio.adlink.de
0.0.0.0 west.adlink.de
0.0.0.0 rc.de.adlink.net #[Tracking.Cookie]
0.0.0.0 tr.de.adlink.net
0.0.0.0 n.admagnet.net
0.0.0.0 ads3.adman.gr #[Tracking.Cookie]
0.0.0.0 gazzetta.adman.gr
0.0.0.0 r2d2.adman.gr
0.0.0.0 talos.adman.gr
0.0.0.0 adman.in.gr
0.0.0.0 admarket.cz
0.0.0.0 www.admarket.cz
0.0.0.0 bridge.ame.admarketplace.net #[Spamdexing]
0.0.0.0 bridge.sf.admarketplace.net
0.0.0.0 a1.admaster.net
0.0.0.0 img.admaster.net
0.0.0.0 admedien.com
0.0.0.0 www.admedien.com
0.0.0.0 apps.admission.net #[Spotlight Ads]
0.0.0.0 appcache.admission.net
0.0.0.0 dt.admission.net
0.0.0.0 view.admission.net
0.0.0.0 ad.admitad.com
0.0.0.0 cdn.admitad.com
0.0.0.0 www.ad.admitad.com
0.0.0.0 cdn.admixer.net
0.0.0.0 ads.admodus.com #[Tracking.Cookie]
0.0.0.0 run.admost.com
0.0.0.0 assets3.admulti.com
0.0.0.0 go.admulti.com
0.0.0.0 s.admulti.com
0.0.0.0 ads.adnet.am
0.0.0.0 ad.adnet.biz #[Tracking.Cookie]
0.0.0.0 adnet.com.ua
0.0.0.0 delivery.adnetwork.vn
0.0.0.0 img.adnet.com.tr
0.0.0.0 www.ad-net.co.uk
0.0.0.0 adnext.fr
0.0.0.0 cdn.adnotch.com
0.0.0.0 ad.adnow.com
0.0.0.0 tt11.adobe.com #[adobe.tcliveus.com]
0.0.0.0 ace.adoftheyear.com
0.0.0.0 ad01.adonspot.com
0.0.0.0 ad02.adonspot.com
0.0.0.0 adperium.com
0.0.0.0 adk2.adperium.com
0.0.0.0 www.adperium.com
0.0.0.0 img.adplan-ds.com
0.0.0.0 res.adplus.co.id
0.0.0.0 e.adpower.bg
0.0.0.0 ab.adpro.com.ua
0.0.0.0 adpublimo.com
0.0.0.0 pop.adrent.net
0.0.0.0 adroll.com
0.0.0.0 rtt.adrolays.de
0.0.0.0 n.ads1-adnow.com
0.0.0.0 n.ads2-adnow.com
0.0.0.0 n.ads3-adnow.com
0.0.0.0 vu.adschoom.com
0.0.0.0 core1.adservingfactory.com
0.0.0.0 content.adservingfactory.com
0.0.0.0 track.adservingfactory.com
0.0.0.0 p78878.adskape.ru
0.0.0.0 map2.adsniper.ru
0.0.0.0 f-nod2.adsniper.ru
0.0.0.0 content.adspynet.com
0.0.0.0 engine.adspynet.com
0.0.0.0 ads.adsready.com
0.0.0.0 ads.adsurve.com
0.0.0.0 www.adsurve.com
0.0.0.0 cntr.adrime.com
0.0.0.0 images.adrime.com #[Adsolutions]
0.0.0.0 ad.adriver.ru
0.0.0.0 content.adriver.ru
0.0.0.0 ssp.adriver.ru
0.0.0.0 r.adrolays.de
0.0.0.0 adrotate.se
0.0.0.0 www.adrotate.net
0.0.0.0 delivery.ads-creativesyndicator.com
0.0.0.0 adsafiliados.com.br
0.0.0.0 ad.adsafiliados.com.br
0.0.0.0 v2.adsbookie.com
0.0.0.0 rh.adscale.de
0.0.0.0 assets.adtaily.com
0.0.0.0 viewster-service.adtelligence.de
0.0.0.0 adtgs.com
0.0.0.0 fusion.adtoma.com
0.0.0.0 core.adunity.com
0.0.0.0 engage2.advanstar.com
0.0.0.0 ddnk.advertur.ru
0.0.0.0 ds.advg.jp
0.0.0.0 m.adx.bg
0.0.0.0 www.adshost2.com
0.0.0.0 js.adscale.de
0.0.0.0 ih.adscale.de
0.0.0.0 adscendmedia.com
0.0.0.0 adservicedomain.info
0.0.0.0 adserver-voice-online.co.uk
0.0.0.0 adsfac.net #[Facilitate Tracking Code]
0.0.0.0 adsgangsta.com
0.0.0.0 adsfac.eu
0.0.0.0 ad.ad-srv.net
0.0.0.0 www.adshot.de
0.0.0.0 f-nod1.adsniper.ru
0.0.0.0 sync2.adsniper.ru
0.0.0.0 cdn6.adspirit.de
0.0.0.0 www.adspace.be
0.0.0.0 adsplius.lt
0.0.0.0 ads.adsponse.de
0.0.0.0 openx.adtext.ro
0.0.0.0 ads.adtiger.de
0.0.0.0 www.adtiger.de
0.0.0.0 ad.adtoma.com
0.0.0.0 au-01.adtomafusion.com
0.0.0.0 bn-01.adtomafusion.com
0.0.0.0 adv.adtotal.pl #[server down?]
0.0.0.0 rek.adtotal.pl
0.0.0.0 www.adtrade.net
0.0.0.0 www.adtrader.com
0.0.0.0 adtradr.com
0.0.0.0 ads.adtube.de
0.0.0.0 www.adultcommercial.net
0.0.0.0 adultmoneymakers.com
0.0.0.0 tracking.adultsense.com
0.0.0.0 www.adult-tracker.de
0.0.0.0 ad.aduserver.com
0.0.0.0 adv758968.ru
0.0.0.0 advaction.ru
0.0.0.0 euroad1.advantage.as
0.0.0.0 mf.advantage.as
0.0.0.0 mfad1.advantage.as
0.0.0.0 adve.net
0.0.0.0 ad.adver.com.tw
0.0.0.0 apps.advertlets.com
0.0.0.0 www.advertlets.com
0.0.0.0 ads.advertise.net
0.0.0.0 www.advertsponsor.com
0.0.0.0 ad.adverticum.net
0.0.0.0 img.adverticum.net
0.0.0.0 imgs.adverticum.net
0.0.0.0 www.advertising365.com
0.0.0.0 titan.advertserve.com
0.0.0.0 ad.advertstream.com
0.0.0.0 usas1.advfn.com
0.0.0.0 images.adviews.de
0.0.0.0 www.adviews.de
0.0.0.0 ad.adview.pl
0.0.0.0 adp.adview.pl
0.0.0.0 bi.adview.pl
0.0.0.0 chart.advinion.com
0.0.0.0 advizi.ru
0.0.0.0 adv.adwish.net
0.0.0.0 ads.adwitserver.com
0.0.0.0 ad.adworx.at
0.0.0.0 www.ad-z.de
0.0.0.0 ads.afa.net
0.0.0.0 affbeat.com
0.0.0.0 affiliate.affdirect.com
0.0.0.0 sttc.affiliate.hu
0.0.0.0 tr.affiliate.hu
0.0.0.0 img.network.affiliando.com
0.0.0.0 view.network.affiliando.com
0.0.0.0 ads.affiliateclub.com
0.0.0.0 affiliategroove.com
0.0.0.0 banners.affiliatefuture.com
0.0.0.0 images.affiliator.com
0.0.0.0 imp.affiliator.com
0.0.0.0 rotation.affiliator.com
0.0.0.0 media.affiliatelounge.com
0.0.0.0 js.affiliatelounge.com
0.0.0.0 record.affiliatelounge.com
0.0.0.0 web1.affiliatelounge.com
0.0.0.0 banners.affilimatch.de
0.0.0.0 ad.afilo.pl
0.0.0.0 adserwer.afilo.pl
0.0.0.0 ads.afraccess.com
0.0.0.0 ads.aftonbladet.se
0.0.0.0 stats.agent.co.il
0.0.0.0 stats.agentinteractive.com
0.0.0.0 w.ahalogy.com
0.0.0.0 ac.ajur.info #[WebBug]
0.0.0.0 openx.ajur.info
0.0.0.0 adlik2.akavita.com
0.0.0.0 dmtracking2.alibaba.com
0.0.0.0 all2lnk.com
0.0.0.0 ads.allaccess.com.ph
0.0.0.0 adcontent2.allaccess.com.ph
0.0.0.0 adservice.aliexpress.com
0.0.0.0 ad.allstar.cz
0.0.0.0 taobaoafp.allyes.cn
0.0.0.0 bokee.allyes.com
0.0.0.0 demoafp.allyes.com
0.0.0.0 eastmoney.allyes.com
0.0.0.0 smarttrade.allyes.com
0.0.0.0 sroomafp.allyes.com
0.0.0.0 taobaoafp.allyes.com
0.0.0.0 tom.allyes.com
0.0.0.0 uuseeafp.allyes.com
0.0.0.0 yeskyafp.allyes.com
0.0.0.0 eas.almamedia.fi
0.0.0.0 ad.altervista.org
0.0.0.0 pqwaker.altervista.org
0.0.0.0 adimg.alice.it
0.0.0.0 adv.alice.it
0.0.0.0 advloc.alice.it
0.0.0.0 altmedia101.com
0.0.0.0 www.alwayson-network.com
0.0.0.0 adtools2.amakings.com
0.0.0.0 banner.amateri.cz
0.0.0.0 amazing-offers.co.il
0.0.0.0 ad.amgdgt.com
0.0.0.0 adserver.amna.gr
0.0.0.0 10394-127.ampxchange.com #[Spamdexing]
0.0.0.0 10394-4254.ampxchange.com
0.0.0.0 10394-2468.ampxchange.com
0.0.0.0 vfdeprod.amobee.com
0.0.0.0 widgets.amung.us
0.0.0.0 whos.amung.us #[WebBug]
0.0.0.0 analytics.analytics-egain.com
0.0.0.0 cloud-us.analytics-egain.com
0.0.0.0 gw.anametrix.net #[WebBug]
0.0.0.0 www.anastasiasaffiliate.com
0.0.0.0 advert.ananzi.co.za
0.0.0.0 advert2.ananzi.co.za
0.0.0.0 box.anchorfree.net
0.0.0.0 rpt.anchorfree.net
0.0.0.0 a.androidandme.com
0.0.0.0 analytics.androidandme.com #[Piwik.Analytics]
0.0.0.0 www.anticlown.com
0.0.0.0 antventure.com
0.0.0.0 webtracker.apicasystem.com
0.0.0.0 junior.apk.net
0.0.0.0 openx.apollo.lv
0.0.0.0 ads.asia1.com.sg
0.0.0.0 ads.ask.com #[sv-click.looksmart.com]
0.0.0.0 www.asknew.com #[Spamdexing]
0.0.0.0 stats.asp24.pl
0.0.0.0 ads.aspalliance.com
0.0.0.0 www.astalavista.us
0.0.0.0 atemda.com
0.0.0.0 logw349.ati-host.net
0.0.0.0 rules.atgsvcs.com
0.0.0.0 logw312.ati-host.net
0.0.0.0 p.ato.mx
0.0.0.0 s.ato.mx
0.0.0.0 ads.auctionads.com
0.0.0.0 banners.audioholics.com
0.0.0.0 ad.auditude.com
0.0.0.0 ads.auctioncity.co.nz
0.0.0.0 d.audienceiq.com
0.0.0.0 ads.autoscout24.com
0.0.0.0 ads.autotrader.com
0.0.0.0 adserving.autotrader.com
0.0.0.0 profiling.avandor.com
0.0.0.0 avantlink.com
0.0.0.0 www.avantlink.com
0.0.0.0 fhg.avrevenue.com #[server down?]
0.0.0.0 rev.avsforum.com
0.0.0.0 ads.avusa.co.za
0.0.0.0 engine.awaps.net
0.0.0.0 analytics.aweber.com
0.0.0.0 clicks.aweber.com #[affects newsletters]
0.0.0.0 tracker.azet.sk
0.0.0.0 www.azmsoft.com

Referência

https://en.wikipedia.org/wiki/Hosts_(file)

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Breno RdV

Software Architect and Backend Developer (almost Fullstack), I usually work with C#, PowerShell, Python, Golang, bash and Unity (this one is more for a hobby). I'm always looking for something new to learn, adding new tools to my utility belt.

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