Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
sukl.cz
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-14 06:37:53 UTC · ↺ Refresh
MX Hostnames
- sukl-cz.f-v1.mx.microsoft
MX Priorities
- sukl-cz.f-v1.mx.microsoft: 0
A / AAAA Records
- 46.30.92.87 (no PTR)
Mail Server IPs
- 52.101.73.28 ↩ mail-am7pr05cu00204.inbound.protection.outlook.com
- 52.101.68.3 ↩ mail-db7pr03cu00403.inbound.protection.outlook.com
- 52.101.68.15 ↩ mail-db6pr03cu00107.inbound.protection.outlook.com
- 52.101.73.26 ↩ mail-as9pr05cu01302.inbound.protection.outlook.com
- 2a01:111:f403:ca04::d ↩ mail-db6pr03cu00105.inbound.protection.outlook.com
- 2a01:111:f403:ca04::4 ↩ mail-db4pr02cu00204.inbound.protection.outlook.com
- 2a01:111:f403:ca04::5 ↩ mail-db3pr0202cu00205.inbound.protection.outlook.com
- 2a01:111:f403:ca04::9 ↩ mail-db7pr03cu00601.inbound.protection.outlook.com
SOA Record
Raw SOA
nsf1.sukl.cz hostmaster.sukl.cz 2026010600 86400 7200 1209600 1800
Primary NS (mname)
nsf1.sukl.cz
Admin Email (rname)
hostmaster@sukl.cz
Serial
2026010600
Refresh
86400s
Retry
7200s
Expire
1209600s
Minimum TTL
1800s
Nameservers (NS)
nsf6.sukl.cz
nsf2.sukl.cz
nsf1.sukl.cz
nsf5.sukl.cz
SPF Record
✓ Strict (-all)
v=spf1 ip4:46.30.88.68/32 ip4:46.30.88.69/32 ip4:88.208.65.55/32 ip4:185.145.37.160/27 ip4:212.224.105.0/26 ip4:195.24.76.170/32 ip6:2001:67c:15a0::/46 ip6:2001:67c:1590::/47 include:spf.protection.outlook.com include:spf.reenio.cz -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected]; sp=quarantine; ri=86400; pct=100;
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: quarantine
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
3 records- ICxo/mAMDdaNlENRwj5Mu88k8M/0f0IXF+gOzjbQTVPbE2jp44hyGjAJEx0G5y0S5OHn76J4L3DZcUnu09+qxQ==
- SPFv=spf1 ip4:46.30.88.68/32 ip4:46.30.88.69/32 ip4:88.208.65.55/32 ip4:185.145.37.160/27 ip4:212.224.105.0/26 ip4:195.24.76.170/32 ip6:2001:67c:15a0::/46 ip6:2001:67c:1590::/47 include:spf.protection.outlook.com include:spf.reenio.cz -all
- MS=ms49799193
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