Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
mastery.net
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-21 03:35:36 UTC · ↺ Refresh
MX Hostnames
- mastery-net.mail.protection.outlook.com
MX Priorities
- mastery-net.mail.protection.outlook.com: 0
A / AAAA Records
- 104.18.20.77 (no PTR)
- 104.18.21.77 (no PTR)
- 2606:4700::6812:154d
- 2606:4700::6812:144d
Mail Server IPs
- 52.101.41.22 ↩ mail-sj2pr05cu00406.inbound.protection.outlook.com
- 52.101.50.13 ↩ mail-mw2pr02cu00605.inbound.protection.outlook.com
- 52.101.194.19 ↩ mail-ch5pr02cu00303.inbound.protection.outlook.com
- 52.101.9.5 ↩ mail-mn2pr04cu00205.inbound.protection.outlook.com
- 2a01:111:f403:f902::1 ↩ mail-bl2pr02cu00101.inbound.protection.outlook.com
- 2a01:111:f403:f910:: ↩ mail-cy5pr03cu00300.inbound.protection.outlook.com
- 2a01:111:f403:c91d::a ↩ mail-co1pr21cu00202.inbound.protection.outlook.com
- 2a01:111:f403:f902:: ↩ mail-bl2pr04cu00100.inbound.protection.outlook.com
SOA Record
Raw SOA
mira.ns.cloudflare.com dns.cloudflare.com 2399488123 10000 2400 604800 1800
Primary NS (mname)
mira.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2399488123
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
mira.ns.cloudflare.com
wesley.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:_spf.salesforce.com include:sendgrid.net include:spf.us.exclaimer.net include:_spf.psm.knowbe4.com include:_spf.ultipro.com include:242477895.spf05.hubspotemail.net include:relay.mailchannels.net ip4:135.84.68.123 -all
📊 DNS lookups: 8/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; pct=100; fo=1; rua=mailto:[email protected]; ruf=mailto:[email protected]
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
24 records- docusign=86474a7f-6218-42d3-840c-58cfe03a844f
- apple-domain-verification=0hdBG2ft5zw6Fi2E
- google-site-verification=KndhMkiYBSZRYfPk4HFkXz6l5huBVc7rugZaWDZayYo
- _globalsign-domain-verification=f4e8FvvfaIgSFeRziuIuyM7f9-Fl6pcBaz9225Y4Rg
- _globalsign-domain-verification=m5knt-G9COgl6ppStapTZa4JegilWSFweoYxhULOi6
- 8n2b6pby1bjc3yf0tf3bt9whw8h28p25
- smartsheet-site-validation=2wQPtgPQawnARRei62qHdrI7_9z9ijJ2
- atlassian-sending-domain-verification=6c55f7ee-5504-48da-8b6e-3e28556b895e
- confluent-verification=b963e90a-7476-4a67-b6b4-2afb527b06f1
- amazon-business-verification=80f527c7c8d278c16d83400745a2703111c87fa7e026b907904a2dccdcc9cd79
- twilio-domain-verification=76e5c598f56ef4fb60432f4723ab4029
- slack-domain-verification=1lfvVck3ychQxz36DySQHz6N8vIQSX1PMZFOKwvu
- bcc9a97c-c81c-4cbf-84f3-9151a7a47950
- atlassian-domain-verification=sknAa6AVng4i7QsI5iaCV1z5hgAf5nKkZ8IewntM8x1a81DEjtXSwlPhWy7s32A7
- google-site-verification=9bW8nP03gCI39xYsB4gZbt8N2lBb6s3EBPudpv7IHRY
- SPFv=spf1 include:spf.protection.outlook.com include:_spf.salesforce.com include:sendgrid.net include:spf.us.exclaimer.net include:_spf.psm.knowbe4.com include:_spf.ultipro.com include:242477895.spf05.hubspotemail.net include:relay.mailchannels.net ip4:135.84.68.123 -all
- asv=deae6a54a8295ecb7a9fea054fb4fd75
- ZOOM_verify_i844J7CmSp6r7UWAWQwumw
- 1password-site-verification=CKWCZZHHFJDBJPJZUPECT5VJYA
- gtzDlNNjjgN6eeeUgw0Rt2MFvTO0JuGEAwjJuTTIubQ=
- mscid=hzGUg2jolA5oBLgA/rUVVRxdVv7eqUCmScbNC+QuN7MR9nsIJ2wsEdWw93iPw34plNRCmyZpMkPLtFnxhi96mw==
- new-relic-domain-verification=4e22658320334caa873c42566c9c6bd3
- browserstack-domain-verification=fc8fb209-70eb-49dc-8b57-d7f82dd17505
- rippling-domain-verification=746c0b4f7bc82d9e
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