Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rkstock.cz
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-24 04:16:27 UTC · ↺ Refresh
MX Hostnames
- rkstock-cz.mail.protection.outlook.com
MX Priorities
- rkstock-cz.mail.protection.outlook.com: 10
A / AAAA Records
- 88.86.121.80 ↩ kvapem.stable.cz
Mail Server IPs
- 52.101.73.1 ↩ mail-am3pr04cu00501.inbound.protection.outlook.com
- 52.101.68.5 ↩ mail-du2pr03cu00105.inbound.protection.outlook.com
- 52.101.68.3 ↩ mail-db7pr03cu00403.inbound.protection.outlook.com
- 52.101.73.8 ↩ mail-am0pr04cu00500.inbound.protection.outlook.com
- 2a01:111:f403:ca09::8 ↩ mail-as2pr05cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca09::e ↩ mail-am7pr05cu00206.inbound.protection.outlook.com
- 2a01:111:f403:ca04::10 ↩ mail-dbapr03cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca09::3 ↩ mail-am6pr04cu00303.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1.websupport.cz admin.websupport.cz 1742236596 7200 2048 1048576 2560
Primary NS (mname)
ns1.websupport.cz
Admin Email (rname)
admin@websupport.cz
Serial
1742236596
Refresh
7200s
Retry
2048s
Expire
1048576s
Minimum TTL
2560s
Nameservers (NS)
ns3.websupport.eu
ns1.websupport.cz
ns2.websupport.cz
SPF Record
✓ Soft Fail (~all)
v=spf1 include:spf.sendinblue.com mx ~all
📊 DNS lookups: 2/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; pct=100
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 3 found
selector1._domainkey
selector2._domainkey
mail._domainkey
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
4 records- sendinblue-code:5082a1dddf4409cfaf5914abf92da9de
- MS=ms81178526
- SPFv=spf1 include:spf.sendinblue.com mx ~all
- SPFv=spf1 include:spf.protection.outlook.com -all
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