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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
84
GRADE
B
FIX
0
REVIEW
4
PASS
4
INFO
1
Probed from Singapore, Singapore
301 Moved Permanently
Checks
9
4 PASS 4 REVIEW
C
DNS Records
Action
1 A records, 211 ms lookup
REVIEW
1 A records, 211 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 23.202.136.150
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
Has 2 IPv6 (AAAA) record(s)
Got: 2600:1413:b000:390::1b62, 2600:1413:b000:38d::1b62
Warning::
CNAME record at zone apex
A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.
Got: e7010.dscg.akamaiedge.net
Info::
No NS records found
Info::
No MX records — email not configured via DNS
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Warning::
DNS resolution is slow (211 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 211 ms
A23.202.136.150
AAAA2600:1413:b000:390::1b62, 2600:1413:b000:38d::1b62
CNAMEe7010.dscg.akamaiedge.net
NS—
MX—
TXT—
CAALookup not available with standard resolver
Resolved in 211 ms

Multiple A records provide failover if one server goes down.

Why this matters

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

A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.

Why this matters

CNAME at the apex (example.com) breaks every other apex record (MX, TXT, NS) — DNS-protocol violation per RFC 1034.

Learn more ▾

RFC 1034 forbids CNAME alongside other records at the same name. Some DNS providers offer ALIAS / ANAME / flattened-CNAME records that work around this — use those instead. Otherwise apex-level CNAME breaks email (no MX), domain ownership verification (no TXT), and more.

Source: RFC 1034

CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.

Why this matters

Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.

SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.

Why this matters

Without SPF, receiving servers can't validate sending IPs — your domain is easier to spoof in phishing.

Learn more ▾

SPF complements DMARC. Both should be published. SPF records list authorized sending IPs (e.g., `v=spf1 include:_spf.google.com ~all` for Google Workspace). After publishing, verify in Google Postmaster Tools or mxtoolbox.

Source: RFC 7208 (SPF)

Slow DNS adds latency to every page load. Consider a faster DNS provider.

Why this matters

DNS resolution is slow — anycast DNS providers (Cloudflare, Route 53) typically resolve <50ms globally.

Source: DNS performance benchmarks

C
Crawlability
Action
robots.txt present, sitemap with 0 URLs
REVIEW
robots.txt present, sitemap with 0 URLs
Info::
robots.txt is present
Got: 127 bytes
Info::
sitemap.xml is present
Warning::
sitemap.xml contains invalid XML
Search engines may not be able to parse the sitemap. Fix XML validation errors.
Warning::
sitemap.xml is empty — no URLs found
An empty sitemap provides no value. Add <url> entries for your pages.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Search engines may not be able to parse the sitemap. Fix XML validation errors.

Why this matters

An unparseable sitemap is silently ignored by Google — the URLs it advertises are never queued for crawl.

Learn more ▾

Google's sitemap parser is strict about XML validity. A single unescaped `&` or unclosed tag invalidates the whole file. Run your sitemap through a validator (Search Console's Sitemaps report flags it) and fix the offending entry. Most generators escape correctly; mistakes usually come from manually-written entries.

Source: sitemaps.org / Google Search Central

An empty sitemap provides no value. Add <url> entries for your pages.

Why this matters

An empty sitemap signals 'no content to index' to Google — actively harmful versus having no sitemap at all.

Learn more ▾

Google compares URLs in the sitemap against URLs it has crawled. An empty sitemap on a site with thousands of pages signals abandonment. Either populate it correctly (most CMSes auto-generate) or delete the file and let Google crawl normally.

Source: Google Search Central / sitemaps.org

Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Why this matters

robots.txt omits Sitemap: directive — crawlers must fetch /sitemap.xml by convention; reliable but missing the explicit hint.

Source: sitemaps.org

robots.txt 200 OK
Size 127 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
# Comcast 

# robots.txt for http://www.comcast.net

# Modified on 1/25/2017

# Hosted on the Edge


User-agent: *

Disallow:
sitemap.xml 200 OK
Type URL Set URLs 0 entries Valid XML No
B
TLS Certificate Expiry & Recommendations
197 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

197
days left
0d 30d 60d 90d+

Recommended actions

  • Enable HSTS: Strict-Transport-Security: max-age=31536000; includeSubDomains
  • 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
B
CDN & Delivery
Akamai
REVIEW
Akamai
Info::
Site is served via Akamai CDN
Got: server header
CDN Detected: Akamai
Provider Akamai Evidence server header
A
Redirect Chain
1 redirect(s), 230 ms total
PASS
1 redirect(s), 230 ms total
Info::
Single redirect
Got: https://www.comcast.net → https://www.xfinity.com/ (301)
Info::
Cross-domain redirect detected

https://www.comcast.net

206 ms · HTTP/1.1

301

https://www.xfinity.com/

24 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.comcast.net301206 msHTTP/1.1AkamaiGHost
2https://www.xfinity.com/40324 msHTTP/1.1

See the visual redirect chain in the HTTP Probe tab →

A+
IPv6 Readiness
IPv6 reachable (1 ms)
PASS
IPv6 reachable (1 ms)
Info::
IPv6 is configured and reachable at 2600:1413:b000:390::1b62, 2600:1413:b000:38d::1b62
Got: 1 ms connect
IPv6 Ready
AAAA Records 2600:1413:b000:390::1b62, 2600:1413:b000:38d::1b62 Connection Reachable (1 ms)
A+
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.comcast.net/
https://comcast.net/

HTTP → HTTPS

301http://www.comcast.net/ → https://www.xfinity.com/

Consistent

A+
HTTP Probe Timing
Total 220 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
198 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
1 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
20 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
220 ms
Total Time Total request time from DNS lookup through full response.
220 ms

Connection waterfall

DNS Lookup 198 ms TCP Connect 1 ms TLS Handshake 20 ms Server Processing 2 ms Content Transfer 0 ms
Domain Intelligence
Domain intelligence data not available
INFO
Domain intelligence data not available

RDAP and WHOIS lookup both failed

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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