seo - 网站为什么使用不同类型的机器人 txt？

Question

大家好，我浏览了很多网站，但我发现了一种不同类型的机器人 txt 任何人都可以帮助我知道为什么使用这种类型的机器人 txt

这个的优点和缺点是什么....

User-Agent: Googlebot-Images
Disallow: 

User-agent: OmniExplorer_Bot
Disallow: 

User-agent: FreeFind
Disallow: 

User-agent: BecomeBot
Disallow: 

User-agent: Nutch
Disallow: 

User-agent: Jetbot/1.0
Disallow: 

User-agent: Jetbot
Disallow: 

User-agent: WebVac
Disallow: 

User-agent: Stanford
Disallow: 

User-agent: naver
Disallow: 

User-agent: dumbot
Disallow: 

User-agent: Hatena Antenna
Disallow: 

User-agent: grub-client
Disallow: 

User-agent: grub
Disallow: 

User-agent: looksmart
Disallow: 

User-agent: WebZip
Disallow: 

User-agent: larbin
Disallow: 

User-agent: b2w/0.1
Disallow: 

User-agent: Copernic
Disallow: 

User-agent: psbot
Disallow: 

User-agent: Python-urllib
Disallow: 

User-agent: NetMechanic
Disallow: 

User-agent: URL_Spider_Pro
Disallow: 

User-agent: CherryPicker
Disallow: 

User-agent: EmailCollector
Disallow: 

User-agent: EmailSiphon
Disallow: 

User-agent: WebBandit
Disallow: 

User-agent: EmailWolf
Disallow: 

User-agent: ExtractorPro
Disallow: 

User-agent: CopyRightCheck
Disallow: 

User-agent: Crescent
Disallow: 

User-agent: SiteSnagger
Disallow: 

User-agent: ProWebWalker
Disallow: 

User-agent: CheeseBot
Disallow: 

User-agent: LNSpiderguy
Disallow: 

User-agent: Mozilla
Disallow: 

User-agent: mozilla
Disallow: 

User-agent: mozilla/3
Disallow: 

User-agent: mozilla/4
Disallow: 

User-agent: mozilla/5
Disallow: 

User-agent: Mozilla/4.0 (compatible; MSIE 4.0; Windows NT)
Disallow: 

User-agent: Mozilla/4.0 (compatible; MSIE 4.0; Windows 95)
Disallow: 

User-agent: Mozilla/4.0 (compatible; MSIE 4.0; Windows 98)
Disallow: 

User-agent: Mozilla/4.0 (compatible; MSIE 4.0; Windows XP)
Disallow: 

User-agent: Mozilla/4.0 (compatible; MSIE 4.0; Windows 2000)
Disallow: 

User-agent: ia_archiver
Disallow: 

User-agent: ia_archiver/1.6
Disallow: 

User-agent: Alexibot
Disallow: 

User-agent: Teleport
Disallow: 

User-agent: TeleportPro
Disallow: 

User-agent: Stanford Comp Sci
Disallow: 

User-agent: MIIxpc
Disallow: 

User-agent: Telesoft
Disallow: 

User-agent: Website Quester
Disallow: 

User-agent: moget/2.1
Disallow: 

User-agent: WebZip/4.0
Disallow: 

User-agent: WebStripper
Disallow: 

User-agent: WebSauger
Disallow: 

User-agent: WebCopier
Disallow: 

User-agent: NetAnts
Disallow: 

User-agent: Mister PiX
Disallow: 

User-agent: WebAuto
Disallow: 

User-agent: TheNomad
Disallow: 

User-agent: WWW-Collector-E
Disallow: 

User-agent: RMA
Disallow: 

User-agent: libWeb/clsHTTP
Disallow: 

User-agent: asterias
Disallow: 

User-agent: httplib
Disallow: 

User-agent: turingos
Disallow: 

User-agent: spanner
Disallow: 

User-agent: InfoNaviRobot
Disallow: 

User-agent: Harvest/1.5
Disallow: 

User-agent: Bullseye/1.0
Disallow: 

User-agent: Mozilla/4.0 (compatible; BullsEye; Windows 95)
Disallow: 

User-agent: Crescent Internet ToolPak HTTP OLE Control v.1.0
Disallow: 

User-agent: CherryPickerSE/1.0
Disallow: 

User-agent: CherryPickerElite/1.0
Disallow: 

User-agent: WebBandit/3.50
Disallow: 

User-agent: NICErsPRO
Disallow: 

User-agent: Microsoft URL Control - 5.01.4511
Disallow: 

User-agent: DittoSpyder
Disallow: 

User-agent: Foobot
Disallow: 

User-agent: WebmasterWorldForumBot
Disallow: 

User-agent: SpankBot
Disallow: 

User-agent: BotALot
Disallow: 

User-agent: lwp-trivial/1.34
Disallow: 

User-agent: lwp-trivial
Disallow: 

User-agent: http://www.WebmasterWorld.com bot
Disallow: 

User-agent: BunnySlippers
Disallow: 

User-agent: Microsoft URL Control - 6.00.8169
Disallow: 

User-agent: URLy Warning
Disallow: 

User-agent: Wget/1.6
Disallow: 

User-agent: Wget/1.5.3
Disallow: 

User-agent: Wget
Disallow: 

User-agent: LinkWalker
Disallow: 

User-agent: cosmos
Disallow: 

User-agent: moget
Disallow: 

User-agent: hloader
Disallow: 

User-agent: humanlinks
Disallow: 

User-agent: LinkextractorPro
Disallow: 

User-agent: Offline Explorer
Disallow: 

User-agent: Mata Hari
Disallow: 

User-agent: LexiBot
Disallow: 

User-agent: Web Image Collector
Disallow: 

User-agent: The Intraformant
Disallow: 

User-agent: True_Robot/1.0
Disallow: 

User-agent: True_Robot
Disallow: 

User-agent: BlowFish/1.0
Disallow: 

User-agent: http://www.SearchEngineWorld.com bot
Disallow: 

User-agent: http://www.WebmasterWorld.com bot
Disallow: 

User-agent: JennyBot
Disallow: 

User-agent: MIIxpc/4.2
Disallow: 

User-agent: BuiltBotTough
Disallow: 

User-agent: ProPowerBot/2.14
Disallow: 

User-agent: BackDoorBot/1.0
Disallow: 

User-agent: toCrawl/UrlDispatcher
Disallow: 

User-agent: WebEnhancer
Disallow: 

User-agent: suzuran
Disallow: 

User-agent: VCI WebViewer VCI WebViewer Win32
Disallow: 

User-agent: VCI
Disallow: 

User-agent: Szukacz/1.4
Disallow: 

User-agent: QueryN Metasearch
Disallow: 

User-agent: Openfind data gathere
Disallow: 

User-agent: Openfind
Disallow: 

User-agent: Xenu's Link Sleuth 1.1c
Disallow: 

User-agent: Xenu's
Disallow: 

User-agent: Zeus
Disallow: 

User-agent: RepoMonkey Bait & Tackle/v1.01
Disallow: 

User-agent: RepoMonkey
Disallow: 

User-agent: Microsoft URL Control
Disallow: 

User-agent: Openbot
Disallow: 

User-agent: URL Control
Disallow: 

User-agent: Zeus Link Scout
Disallow: 

User-agent: Zeus 32297 Webster Pro V2.9 Win32
Disallow: 

User-agent: Webster Pro
Disallow: 

User-agent: EroCrawler
Disallow: 

User-agent: LinkScan/8.1a Unix
Disallow: 

User-agent: Keyword Density/0.9
Disallow: 

User-agent: Kenjin Spider
Disallow: 

User-agent: Iron33/1.0.2
Disallow: 

User-agent: Bookmark search tool
Disallow: 

User-agent: GetRight/4.2
Disallow: 

User-agent: FairAd Client
Disallow: 

User-agent: Gaisbot
Disallow: 

User-agent: Aqua_Products
Disallow: 

User-agent: Radiation Retriever 1.1
Disallow: 

User-agent: WebmasterWorld Extractor
Disallow: 

User-agent: Flaming AttackBot
Disallow: 

User-agent: Oracle Ultra Search
Disallow: 

User-agent: MSIECrawler
Disallow: 

User-agent: PerMan
Disallow: 

User-agent: searchpreview
Disallow: 

User-agent: sootle
Disallow: 

User-agent: es
Disallow: 

User-agent: Enterprise_Search/1.0
Disallow: 

User-agent: Enterprise_Search
Disallow: 

Answer 1

就目前而言，该文件根本没有做任何有用的事情。它实际上与以下内容完全相同:

User-agent: *
Disallow:

空的 Disallow: 表示“允许一切”，因此您也可以通过使用空的 robots.txt 文件或根本没有任何 robots.txt 文件来获得相同的效果。如果您计划允许所有人抓取所有内容，则无需列出单独的用户代理。

我只能推测为什么这个文件存在。也许它最初有:

User-agent: *
Disallow: /

作为最后两行，(以阻止上面未明确列出的任何爬虫)然后有人删除了这两行以允许一切。或者可能编写该文件的人错误地认为 Disallow: 意味着“阻止一切”。