DNS Records for
co.com
🐛 Hunting for rogue glue records.
DNS Records forco.com
Domain DNS Health Score
78%
Total Tests
40
Passed
31
Critical Issues
1
First-Visit DNS
~35ms
Excellent
Returning Visit
~0ms
Fully cached
CNAME Depth
None
Optimal
TTL Strategy
Balanced
TTL values are well-balanced across record types
DNS Provider
DNS Provider
Avg NS Response
2ms
Fast
These nameservers are responsible for answering queries about your domain
4 Records
ns1.nic.co.com
ns2.nic.co.com
ns3.nic.co.com
ns4.nic.co.com
Source: This information was kindly provided by j.gtld-servers.net 🙏🏼
Good. j.gtld-servers.net has information for your TLD. This confirms your domain is properly delegated.
Good. The parent server has your nameservers listed and they match the actual NS records. This ensures consistent DNS resolution.
Glue Records from Parent Server
Information provided by j.gtld-servers.net
ns1.nic.co.com
Nameserver
IPv4 Addresses:
194.169.218.36IPv6 Addresses:
2001:67c:13cc::1:36ns2.nic.co.com
Nameserver
IPv4 Addresses:
185.24.64.36IPv6 Addresses:
2a04:2b00:13cc::1:36ns3.nic.co.com
Nameserver
IPv4 Addresses:
212.18.248.36IPv6 Addresses:
2a04:2b00:13ee::36ns4.nic.co.com
Nameserver
IPv4 Addresses:
212.18.249.36IPv6 Addresses:
2a04:2b00:13ff::36Note:
Glue records are required for these nameservers since they are under your domain. This prevents circular dependencies in DNS resolution.
| Status | Test name | Information |
|---|---|---|
Authoritative Nameservers | These nameservers are responsible for answering queries about your domain 4 Records ns1.nic.co.comns2.nic.co.comns3.nic.co.comns4.nic.co.comSource: This information was kindly provided by j.gtld-servers.net 🙏🏼 | |
TLD Delegation Check | Good. j.gtld-servers.net has information for your TLD. This confirms your domain is properly delegated. | |
Nameservers Listed at Parent | Good. The parent server has your nameservers listed and they match the actual NS records. This ensures consistent DNS resolution. | |
Glue Records from Parent | Glue Records from Parent ServerInformation provided by j.gtld-servers.net ns1.nic.co.comNameserver IPv4 Addresses: 194.169.218.36IPv6 Addresses: 2001:67c:13cc::1:36ns2.nic.co.comNameserver IPv4 Addresses: 185.24.64.36IPv6 Addresses: 2a04:2b00:13cc::1:36ns3.nic.co.comNameserver IPv4 Addresses: 212.18.248.36IPv6 Addresses: 2a04:2b00:13ee::36ns4.nic.co.comNameserver IPv4 Addresses: 212.18.249.36IPv6 Addresses: 2a04:2b00:13ff::36Note: Glue records are required for these nameservers since they are under your domain. This prevents circular dependencies in DNS resolution. |
ns3.nic.co.com
IPv4 Addresses
212.18.248.36
IPv6 Addresses
2a04:2b00:13ee::36
Authoritative
Non-Recursive
TCP
UDP
TTL: 172,800s (2 days)
ns4.nic.co.com
IPv4 Addresses
212.18.249.36
IPv6 Addresses
2a04:2b00:13ff::36
Authoritative
Non-Recursive
TCP
UDP
TTL: 172,800s (2 days)
ns2.nic.co.com
IPv4 Addresses
185.24.64.36
IPv6 Addresses
2a04:2b00:13cc::1:36
Authoritative
Non-Recursive
TCP
UDP
TTL: 172,800s (2 days)
ns1.nic.co.com
IPv4 Addresses
194.169.218.36
IPv6 Addresses
2001:67c:13cc::1:36
Authoritative
Non-Recursive
TCP
UDP
TTL: 172,800s (2 days)
Good. No nameservers allow recursive queries.
The GLUE records from the parent zone match those from your nameservers. This is important for consistent DNS resolution.
Note: Your nameservers are not under your domain, so additional glue records are not required.
Good. The NS records at all your nameservers are identical.
Good. All nameservers listed at the parent server responded.
All NS records appear to be valid hostnames.
You have 4 nameservers. This meets the minimum requirement, though RFC2182 section 5 recommends at least 3 for better reliability.
Good. All nameservers are answering authoritatively for your domain.
Good. All NS records match between parent and nameservers, as required by RFC1034 section 3.6.
Good. All parent-listed nameservers are reported by your nameservers, as required by RFC1034 section 3.6.
Good. No CNAME records found for NS records, as per RFC1912 section 2.4 and RFC2181 section 10.3.
Warning
Found 1 pair(s) of nameserver IPs in the same /16 subnet. For better redundancy, consider using nameservers on different subnets as recommended by RFC2182 section 5. Affected pairs: 212.18.248.36 and 212.18.249.36. Note: providers using anycast may have geographic redundancy despite shared subnets.
Good. All nameserver IPs (both IPv4 and IPv6) are public, ensuring global accessibility as required by RFC1035.
Good. All DNS servers allow TCP connections, which is required for larger DNS responses as per RFC1035.
Good. All DNS servers allow UDP connections, which is required for standard DNS queries.
Good. Your nameservers appear to be on different networks, providing better redundancy.
Good. All nameservers in your zone are properly registered at the parent. This ensures consistent DNS resolution for all users.
| Status | Test name | Information |
|---|---|---|
Nameserver Records from Zone | ns3.nic.co.comIPv4 Addresses 212.18.248.36 IPv6 Addresses 2a04:2b00:13ee::36 Authoritative Non-Recursive TCP UDP TTL: 172,800s (2 days) ns4.nic.co.comIPv4 Addresses 212.18.249.36 IPv6 Addresses 2a04:2b00:13ff::36 Authoritative Non-Recursive TCP UDP TTL: 172,800s (2 days) ns2.nic.co.comIPv4 Addresses 185.24.64.36 IPv6 Addresses 2a04:2b00:13cc::1:36 Authoritative Non-Recursive TCP UDP TTL: 172,800s (2 days) ns1.nic.co.comIPv4 Addresses 194.169.218.36 IPv6 Addresses 2001:67c:13cc::1:36 Authoritative Non-Recursive TCP UDP TTL: 172,800s (2 days) | |
Open Recursive Queries | Good. No nameservers allow recursive queries. | |
Glue Record Consistency | The GLUE records from the parent zone match those from your nameservers. This is important for consistent DNS resolution. | |
Missing Glue for NS Records | Note: Your nameservers are not under your domain, so additional glue records are not required. | |
Mismatched NS records | Good. The NS records at all your nameservers are identical. | |
DNS servers responded | Good. All nameservers listed at the parent server responded. | |
Name of nameservers are valid | All NS records appear to be valid hostnames. | |
Nameserver Redundancy Check | You have 4 nameservers. This meets the minimum requirement, though RFC2182 section 5 recommends at least 3 for better reliability. | |
Lame Delegation Check | Good. All nameservers are answering authoritatively for your domain. | |
Parent Missing Nameservers | Good. All NS records match between parent and nameservers, as required by RFC1034 section 3.6. | |
Zone Missing Nameservers | Good. All parent-listed nameservers are reported by your nameservers, as required by RFC1034 section 3.6. | |
CNAMEs at Apex Check | Good. No CNAME records found for NS records, as per RFC1912 section 2.4 and RFC2181 section 10.3. | |
NS IP Subnet Diversity | Found 1 pair(s) of nameserver IPs in the same /16 subnet. For better redundancy, consider using nameservers on different subnets as recommended by RFC2182 section 5. Affected pairs: 212.18.248.36 and 212.18.249.36. Note: providers using anycast may have geographic redundancy despite shared subnets. | |
NS IP Public Accessibility | Good. All nameserver IPs (both IPv4 and IPv6) are public, ensuring global accessibility as required by RFC1035. | |
DNS servers allow TCP connection | Good. All DNS servers allow TCP connections, which is required for larger DNS responses as per RFC1035. | |
DNS servers allow UDP connection | Good. All DNS servers allow UDP connections, which is required for standard DNS queries. | |
NS AS Diversity Check | Good. Your nameservers appear to be on different networks, providing better redundancy. | |
Stealth Nameserver Check | Good. All nameservers in your zone are properly registered at the parent. This ensures consistent DNS resolution for all users. |
Info
Primary Nameserver
ns0.nic.co.com
Hostmaster Email
hostmaster.co.com
Serial Number
2014408867
Non-Standard (Unix Timestamp)
A unique version number that changes whenever the zone file is updated
Time Intervals
Refresh900 seconds (15 minutes)
How often secondary nameservers check for updates (20m - 24h)
Retry1800 seconds (30 minutes)
How long to wait before retrying a failed zone transfer (2m - 2h)
Expire6048000 seconds (70 days)
How long secondary servers serve stale zone data (1w - 4w)
TTL3600 seconds (1 hours)
Default time-to-live for resource records (5m - 24h)
SOA Serial numbers per nameserver:
ns3.nic.co.com: 2014408867
ns4.nic.co.com: 2014408867
ns2.nic.co.com: 2014408867
ns1.nic.co.com: 2014408867
Good. All nameservers report the same SOA serial number.
Warning
Warning: Primary nameserver ns0.nic.co.com is not listed in your NS records. MNAME doesn't match a member of the NS RRSET. This is OK but may be problematic with zones using Dynamic Updates.
Info
Your SOA serial number is: 2014408867.
Warning
Warning: SOA REFRESH interval is 900 seconds (15 minutes). This is below the recommended minimum of 1200 seconds as per RFC1912 section 2.2.
Warning
Warning: SOA RETRY value (1800 seconds) is higher than refresh (900 seconds). According to RFC1912 section 2.2, retry should be less than refresh to prevent unnecessary zone transfer attempts.
Warning
Current expire time is 6048000 seconds (70 days).
Warning: Common practice recommends a maximum of 28 days (2419200 seconds) to avoid stale data being served for too long.
Pass
OK. Your SOA MINIMUM TTL is: 3600 seconds (60 minutes). This value is used for negative caching and is within the recommended range of 180-86400 seconds as per RFC2308 section 4.
| Status | Test name | Information |
|---|---|---|
SOA record | Primary Nameserverns0.nic.co.com Hostmaster Emailhostmaster.co.com Serial Number 2014408867 Non-Standard (Unix Timestamp) A unique version number that changes whenever the zone file is updated Time IntervalsRefresh900 seconds (15 minutes) How often secondary nameservers check for updates (20m - 24h) Retry1800 seconds (30 minutes) How long to wait before retrying a failed zone transfer (2m - 2h) Expire6048000 seconds (70 days) How long secondary servers serve stale zone data (1w - 4w) TTL3600 seconds (1 hours) Default time-to-live for resource records (5m - 24h) | |
SOA Serial Consistency | SOA Serial numbers per nameserver:
ns3.nic.co.com: 2014408867
ns4.nic.co.com: 2014408867
ns2.nic.co.com: 2014408867
ns1.nic.co.com: 2014408867
Good. All nameservers report the same SOA serial number. | |
SOA MNAME entry | Warning: Primary nameserver ns0.nic.co.com is not listed in your NS records. MNAME doesn't match a member of the NS RRSET. This is OK but may be problematic with zones using Dynamic Updates. | |
SOA Serial | Your SOA serial number is: 2014408867. | |
SOA REFRESH | Warning: SOA REFRESH interval is 900 seconds (15 minutes). This is below the recommended minimum of 1200 seconds as per RFC1912 section 2.2. | |
SOA RETRY | Warning: SOA RETRY value (1800 seconds) is higher than refresh (900 seconds). According to RFC1912 section 2.2, retry should be less than refresh to prevent unnecessary zone transfer attempts. | |
SOA EXPIRE | Current expire time is 6048000 seconds (70 days).
Warning: Common practice recommends a maximum of 28 days (2419200 seconds) to avoid stale data being served for too long. | |
SOA MINIMUM TTL | OK. Your SOA MINIMUM TTL is: 3600 seconds (60 minutes). This value is used for negative caching and is within the recommended range of 180-86400 seconds as per RFC2308 section 4. |
IPv4 Configuration
Single IPv4 address configuration
IPv4 Addresses
169.60.151.232TTL: 300s
Provides a good balance between propagation speed and DNS loadPass
TTL of 300 seconds provides a good balance between propagation speed and DNS load.
| Status | Test name | Information |
|---|---|---|
A Record Configuration | IPv4 ConfigurationSingle IPv4 address configuration IPv4 Addresses 169.60.151.232TTL: 300s Provides a good balance between propagation speed and DNS load | |
A Record TTL | TTL of 300 seconds provides a good balance between propagation speed and DNS load. |
Info
No AAAA (IPv6) records found. While not required, IPv6 support is recommended for future-proofing your domain and improving accessibility for IPv6 users.
| Status | Test name | Information |
|---|---|---|
IPv6 Support | No AAAA (IPv6) records found. While not required, IPv6 support is recommended for future-proofing your domain and improving accessibility for IPv6 users. |
All nameservers are reporting the same mail server configuration. This consistency ensures reliable email delivery.
Mail Exchange Configuration
| Priority | Mail Server | Actions |
|---|---|---|
10 | mx.spamexperts.com | |
20 | fallbackmx.spamexperts.eu | |
30 | lastmx.spamexperts.net |
All mail server hostnames are properly formatted.
All mail servers use public IP addresses, ensuring global email delivery.
Pass
Mail servers are properly configured without CNAME records.
Warning
Warning: The following IP addresses are shared between multiple mail servers:
38.101.250.150 is shared by: mx.spamexperts.com, fallbackmx.spamexperts.eu
38.89.254.156 is shared by: fallbackmx.spamexperts.eu, lastmx.spamexperts.net
38.71.16.244 is shared by: fallbackmx.spamexperts.eu, lastmx.spamexperts.net
This may indicate suboptimal mail handling distribution.
Reverse DNS Records
All Valid
| PTR Query | Hostname |
|---|---|
150.250.101.38.in-addr.arpa | fe3-r2-in.atl06.l.antispamcloud.com |
156.254.89.38.in-addr.arpa | fe1-r2-in.ch03.l.antispamcloud.com |
244.16.71.38.in-addr.arpa | fe2-r2-in.la10.l.antispamcloud.com |
150.250.101.38.in-addr.arpa | fe3-r2-in.atl06.l.antispamcloud.com |
244.16.71.38.in-addr.arpa | fe2-r2-in.la10.l.antispamcloud.com |
27.75.13.149.in-addr.arpa | fe1-r3-in.fra02.l.antispamcloud.com |
23.104.59.154.in-addr.arpa | fe2-r3-in.ams14.l.antispamcloud.com |
156.254.89.38.in-addr.arpa | fe1-r2-in.ch03.l.antispamcloud.com |
Proper reverse DNS records are essential for email deliverability. Mail servers often check if sending IPs have matching PTR records.
| Status | Test name | Information | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Mail Server Consistency | All nameservers are reporting the same mail server configuration. This consistency ensures reliable email delivery. | |||||||||||||||||||
Mail Server Configuration | Mail Exchange Configuration
| |||||||||||||||||||
Mail Server Hostname Validation | All mail server hostnames are properly formatted. | |||||||||||||||||||
Public IP Validation | All mail servers use public IP addresses, ensuring global email delivery. | |||||||||||||||||||
CNAME Validation | Mail servers are properly configured without CNAME records. | |||||||||||||||||||
IP Uniqueness | Warning: The following IP addresses are shared between multiple mail servers:
38.101.250.150 is shared by: mx.spamexperts.com, fallbackmx.spamexperts.eu
38.89.254.156 is shared by: fallbackmx.spamexperts.eu, lastmx.spamexperts.net
38.71.16.244 is shared by: fallbackmx.spamexperts.eu, lastmx.spamexperts.net
This may indicate suboptimal mail handling distribution. | |||||||||||||||||||
Reverse DNS Records | Reverse DNS RecordsAll Valid
Proper reverse DNS records are essential for email deliverability. Mail servers often check if sending IPs have matching PTR records. |
WWW record type: A
www.
A Record
IPv4 Addresses
173.192.76.171Recommendation
Consider using a CNAME record for better flexibility
| Status | Test name | Information |
|---|---|---|
WWW Configuration | WWW record type: A www. A Record IPv4 Addresses 173.192.76.171Recommendation Consider using a CNAME record for better flexibility |
Error
DNSSEC validation failed. This indicates a problem with your DNSSEC configuration:
• DNSKEY query failed with SERVFAIL
• DS query failed with SERVFAIL
Please check your DNSSEC configuration with your DNS provider.
Pass
Zone transfer (AXFR) is properly restricted. Tested 4 nameservers — all refused the transfer request.
Learn more: https://dnschkr.com/blog/dns-attacks-guide#dns-zone-transfer-attack-axfr
Warning
Warning: Wildcard DNS records found. This means any subdomain will resolve to an IP address, which could pose security risks.
Warning
Warning: Server does not return NXDOMAIN for non-existent domains. This could indicate misconfiguration or intentional wildcard records.
Info
No CAA records found. While optional, CAA records help control which Certificate Authorities can issue certificates for your domain.
Checked 8 common subdomains — none have external CNAME records. No subdomain takeover risk from dangling CNAMEs.
Learn more: https://dnschkr.com/blog/dns-attacks-guide#subdomain-takeover
| Status | Test name | Information |
|---|---|---|
DNSSEC | DNSSEC validation failed. This indicates a problem with your DNSSEC configuration:
• DNSKEY query failed with SERVFAIL
• DS query failed with SERVFAIL
Please check your DNSSEC configuration with your DNS provider. | |
Zone Transfer | Zone transfer (AXFR) is properly restricted. Tested 4 nameservers — all refused the transfer request.
Learn more: https://dnschkr.com/blog/dns-attacks-guide#dns-zone-transfer-attack-axfr | |
Wildcard DNS | Warning: Wildcard DNS records found. This means any subdomain will resolve to an IP address, which could pose security risks. | |
NXDOMAIN Response | Warning: Server does not return NXDOMAIN for non-existent domains. This could indicate misconfiguration or intentional wildcard records. | |
CAA Records | No CAA records found. While optional, CAA records help control which Certificate Authorities can issue certificates for your domain. | |
Subdomain Takeover | Checked 8 common subdomains — none have external CNAME records. No subdomain takeover risk from dangling CNAMEs.
Learn more: https://dnschkr.com/blog/dns-attacks-guide#subdomain-takeover |
Info
Click any row to copy the raw value
v | spf1 mx ip4:169.60.151.232 ip4:184.172.61.109 ip4:169.60.163.139 ip4:169.60.135.222 a:codotcom.kayako.com include:servers.mcsv.net -all |
google-site-verification | 7OcubotXUUSYYCSil8JjPJ_2uxorUHKIpmbUGsV_caA |
Showing 2 of 2 records
Pass
Found SPF record: v=spf1 mx ip4:169.60.151.232 ip4:184.172.61.109 ip4:169.60.163.139 ip4:169.60.135.222 a:codotcom.kayako.com include:servers.mcsv.net -all
Pass
Found DMARC record: v=DMARC1; p=quarantine; sp=none; rua=mailto:[email protected]
Click any row to copy the raw value
google-site-verification | 7OcubotXUUSYYCSil8JjPJ_2uxorUHKIpmbUGsV_caA |
Showing 1 of 1 record
| Status | Test name | Information | ||||||
|---|---|---|---|---|---|---|---|---|
TXT Records | Click any row to copy the raw value
Showing 2 of 2 records | |||||||
SPF Record | Found SPF record: v=spf1 mx ip4:169.60.151.232 ip4:184.172.61.109 ip4:169.60.163.139 ip4:169.60.135.222 a:codotcom.kayako.com include:servers.mcsv.net -all | |||||||
DMARC Record | Found DMARC record: v=DMARC1; p=quarantine; sp=none; rua=mailto:[email protected] | |||||||
Domain Verification | Click any row to copy the raw value
Showing 1 of 1 record |