Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
czso.cz
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-14 05:37:34 UTC · ↺ Refresh
MX Hostnames
- mspool.gts.cz
- smtp3.czso.cz
MX Priorities
- mspool.gts.cz: 300
- smtp3.czso.cz: 50
A / AAAA Records
- 194.48.241.132 ↩ www.czso.cz
- 2001:67c:16c0:f001::130 (no PTR)
Mail Server IPs
- 193.85.201.247 ↩ mailx.ti.cz
- 194.48.241.146 ↩ smtp3.czso.cz
SOA Record
Raw SOA
ns1.websupport.cz admin.websupport.cz 1770044464 7200 2048 1048576 2560
Primary NS (mname)
ns1.websupport.cz
Admin Email (rname)
admin@websupport.cz
Serial
1770044464
Refresh
7200s
Retry
2048s
Expire
1048576s
Minimum TTL
2560s
Nameservers (NS)
ns2.websupport.cz
ns3.websupport.eu
ns1.websupport.cz
SPF Record
✓ Strict (-all)
v=spf1 mx a ip4:194.48.241.146 a:smtp3.czso.cz include:spf.protection.outlook.com -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected];
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 392 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
8 records- trend-micro-v1-domain-verification.c5caef547d06b5f08332a914537a7955=380e4082-0280-4928-b56c-106684be9d71
- DKIMv=DKIM1; k=rsa; h=sha256; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAjBaZgLEPnGJCD5y//GuhGXKuLMl2KoQ2DkfNlJOFMje512pNI2louOUIXvHSVeNSZRCwY7y/lSkzvMSDTLud3UZcWIxjTWTxqTN0l0RQTLvG2V47teNZ4upgSNIs2U0TMe+9qPmrrhhYqOXE45Fw3HzlAawd79ZtIjR+XN8Hoysxb7LFyPnzUODMgNtS6ACNIVX8KtFohWEPcY4aJAABedOs5y3whwrsdgIVThefR9P6dOeZzndwKACXBIcKP8KLQmCoQX4XrAL7gnt625Pa3xpWXiov03KHG6/6OgOnkxbcKxmVLK2pmrQeDtKwgGGk5Y3Q3A8Hyx+rCKb7XPcSnwIDAQAB
- _d60318s85zgg9fhf53n7vgnjy7g73nw
- apple-domain-verification=EwOXhiHf6OM54CjR
- MS=922057F72CB1C68AAB668728133F9D8A15E7F280
- DMARCv=DMARC1; p=reject; rua=mailto:[email protected];
- domain-verification=7dGw5v1BaxygO4p1awqNhZJ4FUQFv3WfWjKfiz9u7IcoiKmpf0
- SPFv=spf1 mx a ip4:194.48.241.146 a:smtp3.czso.cz include:spf.protection.outlook.com -all
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