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301 Moved Permanently - celtf.com
HTTP Status: 301
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])
Server: nginx/1.17.6
Date: Sat, 03 May 2025 04:40:47 GMT
Content-Type: text/html
Content-Length: 169
Connection: keep-alive
Location: https://celtf.com/

HTTP Code 301 Moved Permanently

301 status code means that the requested resource has been permanently moved to a new URL. All future requests should use the new address.

When is Code 301 used?

  • When changing a website domain
  • When modifying URL structures
  • When setting up redirects for SEO

What does Code 301 mean for the user?

The browser will automatically redirect the user to the new address, and search engines will update their indexes.

200 OK - https://celtf.com/
HTTP Status: 200
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])
Server: nginx/1.17.6
Date: Sat, 03 May 2025 04:40:48 GMT
Content-Type: text/html
Content-Length: 10261
Connection: keep-alive
Last-Modified: Thu, 05 Sep 2024 07:06:46 GMT
ETag: "66d95886-2815"
Accept-Ranges: bytes
Strict-Transport-Security: max-age=31536000

HTTP Code 200 OK

200 status code is a standard successful HTTP server response. It means that the client’s request (e.g., from a browser) was successfully processed, and the server is delivering the requested data.

When is Code 200 used?

  • When loading a web page
  • When successfully receiving an API response
  • When processing a form or another HTTP request

What does Code 200 mean for the user?

The user receives content without errors, and the page or application functions properly. If Code 200 is accompanied by data, the browser or program processes and displays it to the user.

GET / HTTP/1.1
Host: celtf.com
Accept: */*
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; [email protected])

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<title data-rh="true">個人で出来るCTF練習サイト | CELTF</title><meta data-rh="true" name="viewport" content="width=device-width,initial-scale=1"><meta data-rh="true" name="twitter:card" content="summary_large_image"><meta data-rh="true" property="og:image" content="https://celtf.com/img/ogimg.png"><meta data-rh="true" name="twitter:image" content="https://celtf.com/img/ogimg.png"><meta data-rh="true" property="og:url" content="https://celtf.com/"><meta data-rh="true" name="docusaurus_locale" content="en"><meta data-rh="true" name="docusaurus_tag" content="default"><meta data-rh="true" name="docsearch:language" content="en"><meta data-rh="true" name="docsearch:docusaurus_tag" content="default"><meta data-rh="true" property="og:title" content="個人で出来るCTF練習サイト | CELTF"><meta data-rh="true" name="description" content="CELTFは個人でCTFの練習を行うためのサービスです。ゲーム感覚で手軽に試すことができます。"><meta data-rh="true" property="og:description" content="CELTFは個人でCTFの練習を行うためのサービスです。ゲーム感覚で手軽に試すことができます。"><link data-rh="true" rel="icon" href="/img/favicon.png"><link data-rh="true" rel="canonical" href="https://celtf.com/"><link data-rh="true" rel="alternate" href="https://celtf.com/" hreflang="en"><link data-rh="true" rel="alternate" href="https://celtf.com/" hreflang="x-default"><script data-rh="true">function maybeInsertBanner(){window.__DOCUSAURUS_INSERT_BASEURL_BANNER&&insertBanner()}function insertBanner(){var n=document.getElementById("__docusaurus-base-url-issue-banner-container");if(n){n.innerHTML='\n<div id="__docusaurus-base-url-issue-banner" style="border: thick solid red; background-color: rgb(255, 230, 179); margin: 20px; padding: 20px; font-size: 20px;">\n   <p style="font-weight: bold; font-size: 30px;">Your Docusaurus site did not load properly.</p>\n   <p>A very common reason is a wrong site <a href="https://docusaurus.io/docs/docusaurus.config.js/#baseUrl" style="font-weight: bold;">baseUrl configuration</a>.</p>\n   <p>Current configured baseUrl = <span style="font-weight: bold; color: red;">/</span>  (default value)</p>\n   <p>We suggest trying baseUrl = <span id="__docusaurus-base-url-issue-banner-suggestion-container" style="font-weight: bold; color: green;"></span></p>\n</div>\n';var e=document.getElementById("__docusaurus-base-url-issue-banner-suggestion-container"),s=window.location.pathname,r="/"===s.substr(-1)?s:s+"/";e.innerHTML=r}}window.__DOCUSAURUS_INSERT_BASEURL_BANNER=!0,document.addEventListener("DOMContentLoaded",maybeInsertBanner)</script><link rel="preconnect" href="https://www.google-analytics.com">
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<div id="__docusaurus-base-url-issue-banner-container"></div><div role="region" aria-label="Skip to main content"><a class="skipToContent_fXgn" href="#__docusaurus_skipToContent_fallback">Skip to main content</a></div><nav aria-label="Main" class="navbar navbar--fixed-top"><div class="navbar__inner"><div class="navbar__items"><button aria-label="Toggle navigation bar" aria-expanded="false" class="navbar__toggle clean-btn" type="button"><svg width="30" height="30" viewBox="0 0 30 30" aria-hidden="true"><path stroke="currentColor" stroke-linecap="round" stroke-miterlimit="10" stroke-width="2" d="M4 7h22M4 15h22M4 23h22"></path></svg></button><a class="navbar__brand" href="/"><div class="navbar__logo"><img src="/img/favicon.png" alt="CELTF" class="themedImage_ToTc themedImage--light_HNdA"><img src="/img/favicon.png" alt="CELTF" class="themedImage_ToTc themedImage--dark_i4oU"></div><b class="navbar__title text--truncate">CELTF</b></a><a class="navbar__item navbar__link" href="/docs/about-celtf/introduction">サイトについて</a><a class="navbar__item navbar__link" href="/docs/about-celtf/manual">操作方法</a><a href="https://fealone.fanbox.cc/" target="_blank" rel="noopener noreferrer" class="navbar__item navbar__link">開発を支援する</a><a href="https://lonesec.com/" target="_blank" rel="noopener noreferrer" class="navbar__item navbar__link">ブログ</a></div><div class="navbar__items navbar__items--right"><a href="https://play.celtf.com/" target="_blank" rel="noopener noreferrer" class="navbar__item navbar__link">CELTFを始める</a><div class="searchBox_ZlJk"></div></div></div><div role="presentation" class="navbar-sidebar__backdrop"></div></nav><div id="__docusaurus_skipToContent_fallback" class="main-wrapper mainWrapper_z2l0"><header class="hero hero--primary heroBanner_UJJx"><div class="container"><div class="hero__logo"><img class="logoImage_CqVr" src="img/favicon.png" alt="icon"></div><h1 class="hero__title">CELTF</h1><p class="hero__subtitle">ゲーム性を重視した CTF練習サイト</p><div class="buttons_pzbO"><div class="getStartedButtons_JYhV"><a href="https://play.celtf.com" target="_blank" rel="noopener noreferrer" class="button button--outline button--secondary button--lg getStartedButton_HGFM">CELTFを始める</a></div><div class="optionButtons_Ysbm"><a href="https://beginner.celtf.com/" target="_blank" rel="noopener noreferrer" class="button button--outline button--secondary button--lg optionButton_My1a">CTFを学びながら体験する</a><a href="https://fealone.fanbox.cc/" target="_blank" rel="noopener noreferrer" class="button button--outline button--secondary button--lg optionButton_My1a">開発を支援する(FANBOX)</a></div></div></div></header><main><section class="features_keug"><div class="container"><div class="row"><div class="col col--4"><div class="text--center"><img class="featureImage_yA8i" src="/img/undraw_hacker_mind.svg" alt="個人で練習"></div><h3>個人で練習</h3><p>練習用サイトで取得したフラグを入力する事で簡単に検証する事ができます。 クリアした結果は保存され、いつでも確認する事ができます。</p></div><div class="col col--4"><div class="text--center"><img class="featureImage_yA8i" src="/img/undraw_web_developer.svg" alt="実践で学ぶ"></div><h3>実践で学ぶ</h3><p>問題形式のCTFとは異なり、実践にフォーカスしたCTF練習サイトです。 難易度で別れた練習サイトから、フラグを探し出す必要が有ります。 難易度ごとに別れているため、入門としても利用できます。</p></div><div class="col col--4"><div class="text--center"><img class="featureImage_yA8i" src="/img/undraw_game_world.svg" alt="ゲーム感覚で楽しく"></div><h3>ゲーム感覚で楽しく</h3><p>簡素な問題形式ではなく、実際のサービスを意識して構成されています。 問題を解くのではなく、サービスを攻撃する当事者としてゲーム感覚でフラグを探査していきます。</p></div></div></div></section></main></div><footer class="footer footer--dark"><div class="container container-fluid"><div class="row footer__links"><div class="col footer__col"><div class="footer__title">Documents</div><ul class="footer__items clean-list"><li class="footer__item"><a class="footer__link-item" href="/docs/about-celtf">サイトについて</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/about-ctf">CTFについて</a></li><li class="footer__item"><a class="footer__link-item" href="/docs/privacy-policy">プライバシーポリシー</a></li></ul></div><div class="col footer__col"><div class="footer__title">Community</div><ul class="footer__items clean-list"><li class="footer__item"><a href="https://twitter.com/xfealonex" target="_blank" rel="noopener noreferrer" class="footer__link-item">Twitter<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 4-6.977 7.07 2.828 2.828 6.977-7.07 4.125 4.172v-11z"></path></svg></a></li></ul></div><div class="col footer__col"><div class="footer__title">More</div><ul class="footer__items clean-list"><li class="footer__item"><a href="https://lonesec.com" target="_blank" rel="noopener noreferrer" class="footer__link-item">Blog<svg width="13.5" height="13.5" aria-hidden="true" viewBox="0 0 24 24" class="iconExternalLink_nPIU"><path fill="currentColor" d="M21 13v10h-21v-19h12v2h-10v15h17v-8h2zm3-12h-10.988l4.035 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Whois info of domain

Domain Name: CELTF.COM
Registry Domain ID: 2562342204_DOMAIN_COM-VRSN
Registrar WHOIS Server: whois.discount-domain.com
Registrar URL: http://gmo.jp
Updated Date: 2024-08-31T14:14:02Z
Creation Date: 2020-09-27T14:56:25Z
Registry Expiry Date: 2025-09-27T14:56:25Z
Registrar: GMO Internet Group, Inc. d/b/a Onamae.com
Registrar IANA ID: 49
Registrar Abuse Contact Email: [email protected]
Registrar Abuse Contact Phone: +81.337709199
Domain Status: ok https://icann.org/epp#ok
Name Server: 01.DNSV.JP
Name Server: 02.DNSV.JP
Name Server: 03.DNSV.JP
Name Server: 04.DNSV.JP
DNSSEC: unsigned
URL of the ICANN Whois Inaccuracy Complaint Form: https://www.icann.org/wicf/
>>> Last update of whois database: 2025-05-03T04:40:37Z <<<
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