Domaincloudflare.com
✓ 23 Pass
⚠ 1 Warn
ℹ 9 Info
Action Items
Failures first, then warnings
Warn
MX Records
Reverse PTR records
WARNING. No PTR records found for MX hosts.
Category
Status
Test name
Information
PARENT
Info
Parent delegation records
Delegation NS records returned by parent zone com (a.gtld-servers.net):
ns3.cloudflare.comglue=[162.159.0.33, 162.159.7.226, 2400:cb00:2049:1::a29f:21, 2400:cb00:2049:1::a29f:7e2] resolved=[162.159.0.33, 162.159.7.226, 2400:cb00:2049:1::a29f:7e2, 2400:cb00:2049:1::a29f:21][TTL=172800]
ns5.cloudflare.comglue=[162.159.2.9, 162.159.9.55, 2400:cb00:2049:1::a29f:209, 2400:cb00:2049:1::a29f:937] resolved=[162.159.2.9, 162.159.9.55, 2400:cb00:2049:1::a29f:209, 2400:cb00:2049:1::a29f:937][TTL=172800]
ns4.cloudflare.comglue=[162.159.1.33, 162.159.8.55, 2400:cb00:2049:1::a29f:121, 2400:cb00:2049:1::a29f:837] resolved=[162.159.1.33, 162.159.8.55, 2400:cb00:2049:1::a29f:837, 2400:cb00:2049:1::a29f:121][TTL=172800]
ns6.cloudflare.comglue=[162.159.3.11, 162.159.5.6, 2400:cb00:2049:1::a29f:30b, 2400:cb00:2049:1::a29f:506] resolved=[162.159.3.11, 162.159.5.6, 2400:cb00:2049:1::a29f:30b, 2400:cb00:2049:1::a29f:506][TTL=172800]
ns7.cloudflare.comglue=[162.159.4.8, 162.159.6.6] resolved=[162.159.4.8, 162.159.6.6, 2400:cb00:2049:1::a29f:408, 2400:cb00:2049:1::a29f:606][TTL=172800]
PARENT
Pass
Nameservers listed at parent
Good. Parent server a.gtld-servers.net has the nameservers listed.
PARENT
Pass
Nameserver IPv4 address records
Good. Every nameserver has IPv4 A records. IPv6 AAAA records are informational only.
PARENT
Pass
DNS Parent sent Glue
Good. Parent response included glue address records.
Category
Status
Test name
Information
NS
Info
NS records
NS records from the nameservers. Address health checks validate IPv4 A records only.
ns3.cloudflare.com[162.159.0.33, 162.159.7.226][TTL=21600]
ns4.cloudflare.com[162.159.1.33, 162.159.8.55][TTL=21600]
ns5.cloudflare.com[162.159.2.9, 162.159.9.55][TTL=21600]
ns6.cloudflare.com[162.159.3.11, 162.159.5.6][TTL=21600]
ns7.cloudflare.com[162.159.4.8, 162.159.6.6][TTL=21600]
NS
Pass
Recursive queries
Good. The nameservers do not allow recursive queries for outside hosts.
ns3.cloudflare.com 162.159.0.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns3.cloudflare.com 162.159.7.226 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.1.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.8.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.2.9 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.9.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.3.11 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.5.6 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.4.8 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.6.6 auth=ok recursion=closed tcp=ok serial=2415557203
NS
Pass
Multiple nameservers
Good. It have 5 nameservers. RFC2182 recommends at least 3.
NS
Pass
Different subnets
Good. Nameservers are on 10 different subnets.
NS
Pass
Public IPs
Good. All nameserver IPv4 addresses are public.
NS
Pass
DNS servers responded
Good. All nameserver IPv4 addresses responded.
ns3.cloudflare.com 162.159.0.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns3.cloudflare.com 162.159.7.226 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.1.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.8.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.2.9 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.9.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.3.11 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.5.6 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.4.8 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.6.6 auth=ok recursion=closed tcp=ok serial=2415557203
NS
Pass
TCP connections
Good. All nameserver IPv4 addresses accept TCP connections on port 53.
ns3.cloudflare.com 162.159.0.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns3.cloudflare.com 162.159.7.226 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.1.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.8.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.2.9 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.9.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.3.11 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.5.6 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.4.8 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.6.6 auth=ok recursion=closed tcp=ok serial=2415557203
NS
Pass
Delegation mismatch
Good. NS records match between parent and authoritative servers.
NS
Pass
SOA serial consistency
Good. All nameservers agree on SOA serial: 2415557203.
ns3.cloudflare.com 162.159.0.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns3.cloudflare.com 162.159.7.226 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.1.33 auth=ok recursion=closed tcp=ok serial=2415557203
ns4.cloudflare.com 162.159.8.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.2.9 auth=ok recursion=closed tcp=ok serial=2415557203
ns5.cloudflare.com 162.159.9.55 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.3.11 auth=ok recursion=closed tcp=ok serial=2415557203
ns6.cloudflare.com 162.159.5.6 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.4.8 auth=ok recursion=closed tcp=ok serial=2415557203
ns7.cloudflare.com 162.159.6.6 auth=ok recursion=closed tcp=ok serial=2415557203
Category
Status
Test name
Information
SOA
Info
SOA record
SOA record details:
Primary NS : ns3.cloudflare.com
Hostmaster : dns@cloudflare.com
Serial : 2415557203
Refresh : 10000
Retry : 2400
Expire : 604800
Min TTL : 300
SOA
Pass
SOA MNAME
OK. ns3.cloudflare.com is listed in the NS records.
SOA
Info
SOA Serial
Current SOA serial is 2415557203. RFC 1912 recommends the YYYYMMDDnn date-based format(Year-Month-Day-Revision).
SOA
Pass
SOA Refresh
Refresh: 10000 (2 hour(s)). OK. Within recommended 1 to 24 hours range.
SOA
Pass
SOA Retry
Retry: 2400 (40 min(s)). OK.
SOA
Pass
SOA Expire
Expire: 604800 (7 day(s)). OK.
SOA
Pass
SOA Minimum TTL
Min TTL: 300 (5 min(s)). OK. RFC2308 recommends 1-3 hours for negative caching.
Category
Status
Test name
Information
MX
Info
MX Records
Current MX records:
5 mxb-canary.global.inbound.cf-emailsecurity.net [172.65.65.66]
5 mxa-canary.global.inbound.cf-emailsecurity.net [172.65.169.99]
10 mxa.global.inbound.cf-emailsecurity.net [172.65.65.97]
10 mxb.global.inbound.cf-emailsecurity.net [172.65.64.78]
MX
Pass
MX count
Zone have 4 MX record(s). Good redundancy.
MX
Pass
MX IPv4 addresses are public
Good. All MX records use public IPv4 addresses.
MX
Pass
MX is hostname
Good. All MX records use hostnames, not IP addresses.
MX
Pass
MX CNAME check
OK. No CNAME records found for MX hosts.
MX
Warn
Reverse PTR records
WARNING. No PTR records found for MX hosts.
172.65.65.66 → (no PTR)
172.65.169.99 → (no PTR)
172.65.65.97 → (no PTR)
172.65.64.78 → (no PTR)
Category
Status
Test name
Information
DNSSEC
Info
DS records
DS records published at parent:
2371 alg=13 digest=2 32996839A6D808AFE3EB4A795A0E6A7A39A76FC52FF228B22B76F6D63826F2B9
DNSSEC
Info
DNSKEY records
DNSKEY records published at child:
34505 alg=13 flags=256 protocol=3
2371 alg=13 flags=257 protocol=3
DNSSEC
Pass
DNSSEC chain
DS records at parent match child DNSKEY records.
Category
Status
Test name
Information
WWW
Info
WWW A Record
www.cloudflare.com resolves to:
104.16.123.96
104.16.124.96
WWW
Info
WWW AAAA (IPv6)
IPv6 addresses:
2606:4700::6810:7c60
2606:4700::6810:7b60
WWW
Pass
WWW IPv4 addresses are public
Good. All WWW IPv4 addresses are public.
WWW
Pass
WWW CNAME
OK. www resolves via A record directly.
Processed in 0.388s · Real DNS resolution via dnspython · Wed, 23 Sep 2026 20:38:12 GMT