Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
alster.tax
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-23 00:16:12 UTC · ↺ Refresh
MX Hostnames
- alster-tax.mail.protection.outlook.com
MX Priorities
- alster-tax.mail.protection.outlook.com: 20
A / AAAA Records
- 84.200.229.181 (no PTR)
Mail Server IPs
- 52.101.170.1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
- 52.101.168.0 ↩ mail-beup281cu00100.inbound.protection.outlook.com
- 52.101.170.2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
- 52.101.170.0 ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
- 2a01:111:f403:ca2d::2 ↩ mail-fr6p281cu00202.inbound.protection.outlook.com
- 2a01:111:f403:ca27:: ↩ mail-beup281cu00100.inbound.protection.outlook.com
- 2a01:111:f403:ca2d:: ↩ mail-fr5p281cu00500.inbound.protection.outlook.com
- 2a01:111:f403:ca2d::1 ↩ mail-fr4p281cu03101.inbound.protection.outlook.com
SOA Record
Raw SOA
shades01.rzone.de hostmaster.strato-rz.de 2021081097 86400 7200 604800 300
Primary NS (mname)
shades01.rzone.de
Admin Email (rname)
hostmaster@strato-rz.de
Serial
2021081097
Refresh
86400s
Retry
7200s
Expire
604800s
Minimum TTL
300s
Nameservers (NS)
shades01.rzone.de
docks18.rzone.de
SPF Record
✓ Soft Fail (~all)
v=spf1 include:spf.protection.outlook.com include:mx1.sohnix-rz.de include:mx2.sohnix-rz.de include:mx3.sohnix-rz.de ip4:84.200.229.181 ip4:85.199.88.61 ip4:62.157.187.148 ip4:85.199.88.15 ~all
📊 DNS lookups: 4/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✓ Reject
v=DMARC1;p=reject;
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
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
2 records- SPFv=spf1 include:spf.protection.outlook.com include:mx1.sohnix-rz.de include:mx2.sohnix-rz.de include:mx3.sohnix-rz.de ip4:84.200.229.181 ip4:85.199.88.61 ip4:62.157.187.148 ip4:85.199.88.15 ~all
- MS=ms27040802
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