Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
optimal-systems.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-28 07:32:24 UTC · ↺ Refresh
MX Hostnames
- mail.optimal-systems.de
MX Priorities
- mail.optimal-systems.de: 100
A / AAAA Records
- 185.76.237.144 (no PTR)
- 2a00:1c98:60:1350::d33a:41a9 (no PTR)
Mail Server IPs
- 20.170.21.100 (no PTR)
SOA Record
Raw SOA
ns-1052.awsdns-03.org awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-1052.awsdns-03.org
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-1052.awsdns-03.org
ns-1951.awsdns-51.co.uk
ns-44.awsdns-05.com
ns-932.awsdns-52.net
SPF Record
✓ Strict (-all)
v=spf1 ip4:213.61.224.33 ip4:46.225.1.76 include:spf.imc-hosting.com include:spf.protection.outlook.com include:spf.sendinblue.com include:_spf.salesforce.com include:amazonses.com mx -all
📊 DNS lookups: 6/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; pct=100; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 5 found
selector1._domainkey
selector2._domainkey
mail._domainkey
s1._domainkey
s2._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- google-site-verification=lfSotKu2ZHccZihZuCrkM-9GPUd5Z-rIegDoXfp-5ko
- SPFv=spf1 ip4:213.61.224.33 ip4:46.225.1.76 include:spf.imc-hosting.com include:spf.protection.outlook.com include:spf.sendinblue.com include:_spf.salesforce.com include:amazonses.com mx -all
- MS=CD74DDF7BE948BDF16DE1686AD97440AA6822211
- MS=ms28370874
- Sendinblue-code:9b1d3422ea4cced23a56732fc28e5bf1
- apple-domain-verification=7R275TA5RWsTq8pl
- atlassian-domain-verification=wB2uJrqE2EGTOA3Ugqv2pZCl/IS79Lc5GeFM7/VtepaS87uD45e4dISzl6DzNDhh
- google-site-verification=0DNmZPk3BVYMtIjbvjW23vK2bGIsOJF8-GB-42StPxU
Full email verification for optimal-systems.de
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