Infrastructure
· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.FIPv6 ReadinessActionIPv6 records exist but unreachableFIX
Having AAAA records but an unreachable server is worse than no AAAA — clients may experience delays before falling back to IPv4.
Advertising IPv6 (AAAA records) without a reachable server means IPv6-preferring clients silently fail every connection.
Learn more ▾ ▴
Modern browsers prefer IPv6 if AAAA exists (Happy Eyeballs algorithm). If the IPv6 server isn't reachable, browsers fall back to IPv4 — but with seconds of added latency per request. Either fix IPv6 reachability or remove the AAAA records.
Source: RFC 8305 (Happy Eyeballs)
DURL VariantsActionwww/non-www, trailing slash, HTTP→HTTPSFIX
www / non-www
Inconsistent — duplicate content risk
HTTP → HTTPS
HTTP version does not redirect to HTTPS
DCDN & DeliveryActionNo CDN detectedFIX
Consider using a CDN to improve global delivery speed and reduce origin load.
BRedirect Chain1 redirect(s), 3431 ms totalREVIEW
https://usgs.gov
997 ms · HTTP/1.1
https://www.usgs.gov/
2434 ms · HTTP/1.1 FINAL
| # | URL | Status | Time | Protocol | Server |
|---|---|---|---|---|---|
| 1 | https://usgs.gov | 301 | 997 ms | HTTP/1.1 | |
| 2 | https://www.usgs.gov/ | 200 | 2434 ms | HTTP/1.1 | nginx |
See the visual redirect chain in the HTTP Probe tab →
BHTTP Probe TimingTotal 914 ms — DNS, TCP, TLS, TTFB, content transfer breakdownREVIEW
Connection waterfall
BTLS Certificate Expiry & Recommendations142 days until leaf cert expires — 2 issues to addressREVIEW
Certificate validity
Recommended actions
- Submit your domain to hstspreload.org to be added to the Chrome preload list
- Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+DNS Records1 A records, 31 ms lookupPASS
| A | 137.227.233.178 |
| AAAA | 2001:49c8:8000:121d::78 |
| CNAME | — |
| NS | ram.ns.cloudflare.com, chin.ns.cloudflare.com |
| MX | 0 usgs-gov.mail.protection.outlook.com |
| TXT | _hbyfgt08dknxtua1v3f76s538skt43l SPF v=spf1 include:_spf.usgs.gov include:_spf.doi.gov include:spf.protection.outlook... amazonses:iCXvgYeeCTBsNF5P4aaQq/gAJE3NWJAehnOg3OAoBJY= docker-verification=0b575962-d656-47f4-8fd5-5175fe2f364b |
| 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+Crawlabilityrobots.txt present, sitemap with 77 URLsPASS
#
# robots.txt
#
# This file is to prevent the crawling and indexing of certain parts
# of your site by web crawlers and spiders run by sites like Yahoo!
# and Google. By telling these "robots" where not to go on your site,
# you save bandwidth and server resources.
#
# This file will be ignored unless it is at the root of your host:
# Used: http://example.com/robots.txt
# Ignored: http://example.com/site/robots.txt
#
# For more information about the robots.txt standard, see:
# http://www.robotstxt.org/robotstxt.html
User-agent: *
# CSS, JS, Images
Allow: /core/*.css$
Allow: /core/*.css?
Allow: /core/*.js$
Allow: /core/*.js?
Allow: /core/*.gif
Allow: /core/*.jpg
Allow: /core/*.jpeg
Allow: /core/*.png
Allow: /core/*.svg
Allow: /profiles/*.css$
Allow: /profiles/*.css?
Allow: /profiles/*.js$
Allow: /profiles/*.js?
Allow: /profiles/*.gif
Allow: /profiles/*.jpg
Allow: /profiles/*.jpeg
Allow: /profiles/*.png
Allow: /profiles/*.svg
# Directories
Disallow: /core/
Disallow: /profiles/
# Files
Disallow: /README.txt
Disallow: /web.config
# Paths (clean URLs)
Disallow: /admin/
Disallow: /comment/reply/
Disallow: /filter/tips
Disallow: /node/add/
Disallow: /search/
Disallow: /user/register/
Disallow: /user/password/
Disallow: /user/login/
Disallow: /user/logout/
# Paths (no clean URLs)
Disallow: /index.php/admin/
Disallow: /index.php/comment/reply/
Disallow: /index.php/filter/tips
Disallow: /index.php/node/add/
Disallow: /index.php/search/
Disallow: /index.php/user/password/
Disallow: /index.php/user/register/
Disallow: /index.php/user/login/
Disallow: /index.php/user/logout/
Sitemap: https://www.usgs.gov/sitemap.xml
- https://www.usgs.gov/sitemap.xml?page=1
- https://www.usgs.gov/sitemap.xml?page=2
- https://www.usgs.gov/sitemap.xml?page=3
- https://www.usgs.gov/sitemap.xml?page=4
- https://www.usgs.gov/sitemap.xml?page=5
- https://www.usgs.gov/sitemap.xml?page=6
- https://www.usgs.gov/sitemap.xml?page=7
- https://www.usgs.gov/sitemap.xml?page=8
- https://www.usgs.gov/sitemap.xml?page=9
- https://www.usgs.gov/sitemap.xml?page=10
- https://www.usgs.gov/sitemap.xml?page=11
- https://www.usgs.gov/sitemap.xml?page=12
- https://www.usgs.gov/sitemap.xml?page=13
- https://www.usgs.gov/sitemap.xml?page=14
- https://www.usgs.gov/sitemap.xml?page=15
- https://www.usgs.gov/sitemap.xml?page=16
- https://www.usgs.gov/sitemap.xml?page=17
- https://www.usgs.gov/sitemap.xml?page=18
- https://www.usgs.gov/sitemap.xml?page=19
- https://www.usgs.gov/sitemap.xml?page=20
- https://www.usgs.gov/sitemap.xml?page=21
- https://www.usgs.gov/sitemap.xml?page=22
- https://www.usgs.gov/sitemap.xml?page=23
- https://www.usgs.gov/sitemap.xml?page=24
- https://www.usgs.gov/sitemap.xml?page=25
- https://www.usgs.gov/sitemap.xml?page=26
- https://www.usgs.gov/sitemap.xml?page=27
- https://www.usgs.gov/sitemap.xml?page=28
- https://www.usgs.gov/sitemap.xml?page=29
- https://www.usgs.gov/sitemap.xml?page=30
- https://www.usgs.gov/sitemap.xml?page=31
- https://www.usgs.gov/sitemap.xml?page=32
- https://www.usgs.gov/sitemap.xml?page=33
- https://www.usgs.gov/sitemap.xml?page=34
- https://www.usgs.gov/sitemap.xml?page=35
- https://www.usgs.gov/sitemap.xml?page=36
- https://www.usgs.gov/sitemap.xml?page=37
- https://www.usgs.gov/sitemap.xml?page=38
- https://www.usgs.gov/sitemap.xml?page=39
- https://www.usgs.gov/sitemap.xml?page=40
- https://www.usgs.gov/sitemap.xml?page=41
- https://www.usgs.gov/sitemap.xml?page=42
- https://www.usgs.gov/sitemap.xml?page=43
- https://www.usgs.gov/sitemap.xml?page=44
- https://www.usgs.gov/sitemap.xml?page=45
- https://www.usgs.gov/sitemap.xml?page=46
- https://www.usgs.gov/sitemap.xml?page=47
- https://www.usgs.gov/sitemap.xml?page=48
- https://www.usgs.gov/sitemap.xml?page=49
- https://www.usgs.gov/sitemap.xml?page=50
- https://www.usgs.gov/sitemap.xml?page=51
- https://www.usgs.gov/sitemap.xml?page=52
- https://www.usgs.gov/sitemap.xml?page=53
- https://www.usgs.gov/sitemap.xml?page=54
- https://www.usgs.gov/sitemap.xml?page=55
- https://www.usgs.gov/sitemap.xml?page=56
- https://www.usgs.gov/sitemap.xml?page=57
- https://www.usgs.gov/sitemap.xml?page=58
- https://www.usgs.gov/sitemap.xml?page=59
- https://www.usgs.gov/sitemap.xml?page=60
- https://www.usgs.gov/sitemap.xml?page=61
- https://www.usgs.gov/sitemap.xml?page=62
- https://www.usgs.gov/sitemap.xml?page=63
- https://www.usgs.gov/sitemap.xml?page=64
- https://www.usgs.gov/sitemap.xml?page=65
- https://www.usgs.gov/sitemap.xml?page=66
- https://www.usgs.gov/sitemap.xml?page=67
- https://www.usgs.gov/sitemap.xml?page=68
- https://www.usgs.gov/sitemap.xml?page=69
- https://www.usgs.gov/sitemap.xml?page=70
- https://www.usgs.gov/sitemap.xml?page=71
- https://www.usgs.gov/sitemap.xml?page=72
- https://www.usgs.gov/sitemap.xml?page=73
- https://www.usgs.gov/sitemap.xml?page=74
- https://www.usgs.gov/sitemap.xml?page=75
- https://www.usgs.gov/sitemap.xml?page=76
- https://www.usgs.gov/sitemap.xml?page=77
A+Domain Intelligenceusgs.gov — via get.gov, 28 years, 11 months oldPASS
50 days
September 2, 2026
142 days
Issued by DigiCert Inc
28 years, 11 months
Registered October 2, 1997
Enabled
Protects against DNS spoofing
Unknown
2001:49c8:8000:121d::78
get.gov
Expiry timeline
Recommended actions
- Renew the domain or enable auto-renewal to prevent accidental expiry
- Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
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