zimbra.com

Checked 22 October 2026, 11:43 UTC · via 8.8.8.8
!Passed with warnings
21 passed 6 warnings 0 failed 3 info

SPF

warn

SPF record published

Found

Record
v=spf1 ptr mx ip4:52.7.157.95 ip4:52.70.125.224 ip4:52.204.246.185 ip4:52.205.85.65 ip4:66.64.15.66 ip4:167.89.32.168 ip4:173.227.76.247 ip4:14.141.104.38 ip4:193.122.206.174 ip4:193.122.199.60 ip4:129.213.200.110 ip4:150.136.98.232 ip4:150.136.146.2 ip4:129.80.213.239 ip4:193.122.157.30 ip4:141.148.3.168 ip4:129.213.104.172 ip4:193.122.141.196/32 ip4:150.136.208.81/32 include:us._netblocks.mimecast.com include:_spf.salesforce.com include:212115.spf01.hubspotemail.net include:4366039.spf01.hubspotemail.net -all
DNS lookups
7 of 10
Void lookups
0 of 2

Checks

  • !
    Uses deprecated ptr mechanism
    The ptr mechanism in SPF records is deprecated due to performance issues and should be avoided.
    #1
  • ✓ 7 of 10 DNS lookups #2
    SPF record needs 7 DNS lookups (limit is 10).
  • ✓ Ends with -all #3
    SPF record properly uses -all to restrict unauthorized senders.
  • ✓ Record published #6
    SPF record exists for this domain.
  • ✓ Single record #16
    Exactly one SPF record is published.
  • ✓ Valid syntax #25
    All SPF mechanisms and modifiers are valid.
  • ✓ No void lookups #26
    All include/redirect targets exist.
  • ✓ No overly broad IP ranges #27
    All ip4/ip6 ranges are narrow enough.

DMARC

warn

p=reject (_dmarc.zimbra.com)

Found

Record
v=DMARC1;p=reject;rua=mailto:dmarc@zimbra.com;ruf=mailto:dmarc@zimbra.com;aspf=s;sp=none
Found at
_dmarc.zimbra.com
TagValueMeaning
vDMARC1Version
prejectPolicy
spnoneSubdomain policy
ruamailto:dmarc@zimbra.comAggregate report addresses
rufmailto:dmarc@zimbra.comFailure report addresses
aspfsSPF alignment (r = relaxed, s = strict)

Checks

  • ✓ Policy: reject #4
    DMARC policy is set to 'reject', which provides the strongest protection against email spoofing.
  • ✓ Record published #5
    DMARC record exists for this domain.
  • ✓ Valid syntax #17
    DMARC record syntax is valid.
  • ✓ Applies to 100% of mail #18
    DMARC policy applies to all failing mail.
  • ✓ Aggregate reports enabled #19
    Aggregate reports are sent to: mailto:dmarc@zimbra.com
  • !
    Subdomains unprotected (sp=none)
    DMARC subdomain policy is sp=none, so spoofed mail from subdomains is not blocked. Consider sp=quarantine or sp=reject.
    #20
  • ✓ Report addresses in own domain #29
    All report addresses are in your own organizational domain.

DKIM

warn

No keys found under the checked selectors

Found

Selectors
None found
_domainkey
NOERROR

Checks

  • !
    No key under common selectors
    The _domainkey name exists but no DKIM key was found under the common selectors. Selectors are provider-specific; check yours with -selector.
    #7

DNSSEC

warn

Not signed

Found

DNSKEY records
No (0)
DS at parent
No

Checks

  • !
    Not enabled
    DNSSEC is not enabled for this domain. Consider enabling DNSSEC to protect against DNS spoofing attacks.
    #8

MX

warn

2 mail servers

Found

PriorityHostRecordsReverse DNS
10us-smtp-inbound-1.mimecast.comA 170.10.128.221 A 170.10.128.242 A 170.10.132.221 A 170.10.132.141 A 170.10.128.141 A 170.10.132.242us-smtp-inbound-1.mimecast.com ✓ us-smtp-inbound-1.mimecast.com ✓ us-smtp-inbound-2.mimecast.com ✓ us-smtp-inbound-1.mimecast.com ✓ us-smtp-inbound-2.mimecast.com ✓ us-smtp-inbound-2.mimecast.com ✓
10us-smtp-inbound-2.mimecast.comA 170.10.128.141 A 170.10.128.221 A 170.10.132.141 A 170.10.132.242 A 170.10.128.242 A 170.10.132.221us-smtp-inbound-1.mimecast.com ✓ us-smtp-inbound-2.mimecast.com ✓ us-smtp-inbound-1.mimecast.com ✓ us-smtp-inbound-1.mimecast.com ✓ us-smtp-inbound-1.mimecast.com ✓ us-smtp-inbound-1.mimecast.com ✓

Checks

  • ✓ 2 MX records #9
    Found 2 MX records for this domain.
  • ✓ All hosts resolve #10
    All MX records resolve to valid IP addresses.
  • !
    Hosts without IPv6
    The following MX hosts could not be resolved to IPv6 addresses: us-smtp-inbound-1.mimecast.com, us-smtp-inbound-2.mimecast.com
    #11
  • ✓ Redundant MX hosts #12
    Found 2 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 2 MX records, which is within the recommended range (1-5).
  • ✓ No localhost targets #14
    No MX records pointing to localhost found.
  • ✓ No private IP addresses #15
    No MX records resolving to private IP addresses found.
  • ✓ No CNAME targets #22
    No MX records point to a CNAME.
  • ✓ Reverse DNS confirmed #30
    All 12 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 0 of 2 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
us-smtp-inbound-1.mimecast.comnone-
us-smtp-inbound-2.mimecast.comnone-

Checks

  • !
    Not configured
    MTA-STS is not configured, so other mail servers fall back to unencrypted delivery when TLS fails or is stripped by an attacker. Publish a _mta-sts TXT record and a policy at https://mta-sts.<domain>/.well-known/mta-sts.txt.
    #32
  • i
    Not configured
    TLS-RPT lets senders report TLS delivery problems to you. It is most useful together with MTA-STS or DANE.
    #35
  • i
    Not used
    No MX host publishes TLSA records. DANE lets senders verify your mail server's certificate through DNSSEC; it requires DNSSEC on the MX host's zone.
    #36

BIMI

info

No BIMI record

Checks

  • i
    Not configured
    BIMI shows your logo next to your mail in supporting mail clients. It requires DMARC enforcement.
    #38