Infrastructure
· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.BTLS Certificate Expiry & Recommendations68 days until leaf cert expires — 4 issues to addressREVIEW
Certificate validity
Recommended actions
- Add includeSubDomains to the HSTS directive
- Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
- Enable DNSSEC on your domain for DNS spoofing protection
- Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+DNS Records1 A records, 11 ms lookupPASS
| A | 76.76.21.21 |
| AAAA | 2600:9000:a51d:27c1:6748:d035:a989:fb3c, 2600:9000:a602:b1e6:5b89:50a1:7cf7:67b8 |
| CNAME | — |
| NS | ns-1359.awsdns-41.org, ns-1558.awsdns-02.co.uk, ns-197.awsdns-24.com, ns-557.awsdns-05.net |
| MX | 1 aspmx.l.google.com 5 alt1.aspmx.l.google.com 5 alt2.aspmx.l.google.com 10 alt4.aspmx.l.google.com 10 alt3.aspmx.l.google.com |
| TXT | 723757a747 MS=34DDD317D9FEB51560ED2178552EF5F487EFDA34 MS=ms19736920 MS=ms46037000 anthropic-domain-verification-vpgx4y=uwN6CwOz0NQijKYGDthCAEt9C asv=c034fa773cb1b431402a28453995174d atlassian-domain-verification=nffRaFBNr1PtD33kaEsaD9CvW1YDeLVUva1REQBQXomao5ORxy... atlassian-sending-domain-verification=8ec3fea9-480e-4fea-ad9d-b8106e2f47bd docker-verification=3d97b1d0-f13c-49a5-a608-a4e126994fb2 figma-domain-verification=1c2de6e8a2ed198f2e74b79eb341b1e7fa0c2f8f77d967c3df1a34... google-site-verification=4uv57KflyDjYKic07oPiF5ypArLxQQYp_e-u2RCQ2rE google-site-verification=FdhZ5m0ygy7zoBLQNWvqJ3v0wQop9dTu5ZHYvojZlPE google-site-verification=HHC0j5mcC05kfiQfxmiYUfsicdbGYAJyh0gKySbCcDM google-site-verification=aISd8KPh1T5nM6tv78IhxrYXTvLqrjMLcOsV6tDc9xw google-site-verification=uvcAEZ3qnz0lx7zpKE9DMg7FqYBSPuVK61d7zlxew3g hubspot-domain-verification=ZjA2YWQ4OGMtYTJmMi00NGM3LWJkM2ItZGNjNjYwY2I1NTQ2 notion-domain-verification=5N4i2ZyFxTIAh8yjBjVknqRdZp9BFylUmFFV3h6M3sg openai-domain-verification=dv-3qK0xjzrDgu9vT3wfpM2P0g2 reachdesk-verification=gzGzYoV4RdcIj5gGsLsXBmdtmVBeVfDfro9HrQ2Q6TCsKUF5xQW6PGnmT... stripe-verification=0ba99cfebb16921aa06471ec2581cf92c47b39cb15a8877a174bb78829e1... stripe-verification=5fcd1c876b6a81bf6ec1888417271c54c1a7186b90e858e181224cc31b2c... stripe-verification=a72a667972336ba404d79c4c29f31c0e9226e2260da4c6a4c7dce3af1ec2... stripe-verification=d1e4db8d6a928fe01eaf24de20ea7dc4c6ebc1fa91940e3a6a0cc5908202... SPF v=spf1 include:_spf.google.com include:_spf.salesforce.com include:40004831.spf0... |
| CAA | Lookup not available with standard resolver |
Multiple A records provide failover if one server goes down.
Single A record means a single point of failure — if that IP goes down, your site is unreachable until DNS TTL expires.
Learn more ▾ ▴
Add multiple A records for round-robin failover, or use a managed DNS provider with health-checked failover (Route 53, Cloudflare, NS1). Short TTL (60-300s) lets clients recover faster on outages.
Source: SRE practice / DNS architecture
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.
A+Redirect ChainNo redirects — direct accessPASS
https://tailscale.com
112 ms · HTTP/1.1 FINAL
| # | URL | Status | Time | Protocol | Server |
|---|---|---|---|---|---|
| 1 | https://tailscale.com | 200 | 112 ms | HTTP/1.1 | Vercel |
A+IPv6 ReadinessIPv6 reachable (1 ms)PASS
A+Crawlabilityrobots.txt present, sitemap with 1092 URLsPASS
User-agent: *
Disallow:
User-agent: atlassian-bot
Allow: /docs/
Sitemap: https://tailscale.com/sitemap.xml
AURL Variantswww/non-www, trailing slash, HTTP→HTTPSPASS
www / non-www
HTTP → HTTPS
Use 301 (permanent) instead of 302 (temporary)
A+Domain Intelligencetailscale.com — via MarkMonitor Inc., 8 years, 9 months oldPASS
61 days
August 15, 2026
68 days
Issued by Let's Encrypt
8 years, 9 months
Registered August 15, 2017
Not enabled
Protects against DNS spoofing
Unknown
2600:9000:a51d:27c1:6748:d035:a989:fb3c
MarkMonitor Inc.
Expiry timeline
Recommended actions
- Renew the domain or enable auto-renewal to prevent accidental expiry
- Enable DNSSEC to protect visitors from DNS spoofing
- Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Without DNSSEC, an attacker who can poison your DNS can hijack your domain — and SSL certs alone don't stop them.
Learn more ▾ ▴
DNSSEC adds cryptographic signatures to DNS records, preventing forged responses from poisoning resolver caches. Without it, an attacker who controls the network path can redirect your domain to a malicious server before any HTTPS handshake happens. Most modern registrars (Cloudflare, Google Domains, Route 53) enable it with one toggle.
Source: ICANN / RFC 4033
The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.
Without registrar lock, an attacker who phishes your registrar credentials can transfer the domain in minutes — total brand hijack.
Learn more ▾ ▴
Registrar lock (clientTransferProhibited, clientUpdateProhibited, clientDeleteProhibited) requires extra verification before any transfer/update/delete. Every major registrar offers it free. Combined with 2FA on your registrar account, it's the strongest defense against domain hijacking.
Source: ICANN / domain-security best practice