Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
co.delaware.pa.us
Yes
✓ Yes
Mimecast
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-26 13:50:19 UTC · ↺ Refresh
MX Hostnames
- usb-smtp-inbound-2.mimecast.com
- usb-smtp-inbound-1.mimecast.com
MX Priorities
- usb-smtp-inbound-2.mimecast.com: 10
- usb-smtp-inbound-1.mimecast.com: 10
A / AAAA Records
- 204.13.204.205 ↩ www.co.delaware.pa.us
Mail Server IPs
- 170.10.150.242 ↩ usb-smtp-delivery-2.mimecast.com
- 170.10.152.242 ↩ usb-smtp-delivery-2.mimecast.com
SOA Record
Raw SOA
dns3.dciu.net administrator.co.delaware.pa.us 2006083311 3600 3600 86400 3600
Primary NS (mname)
dns3.dciu.net
Admin Email (rname)
administrator@co.delaware.pa.us
Serial
2006083311
Refresh
3600s
Retry
3600s
Expire
86400s
Minimum TTL
3600s
Nameservers (NS)
dns4.dciu.net
dns2.dciu.net
dns3.dciu.net
SPF Record
✓ Strict (-all)
v=spf1 include:usb._netblocks.mimecast.com include:spf.protection.outlook.com -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 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
12 records- dgp5lej5s619j1r07hhe0l2u4g
- apple-domain-verification=BLSubbjPHql8QRMe
- aesv1coasrvr281o9u0d5c05l4
- IfdQL3blWqP17rpAMqzdqn8XEDJBcwSZ0CPAtpkMDUnrtUmR/LXhDIbIjOfls4numsbGLlnUN/fg6DekOXErsw==
- MS=ms32507081
- _xd61twyecrj9agz3mysu39os90fgbeo
- ap2ahoh1qof4kfil831s07eq1m
- SPFv=spf1 include:usb._netblocks.mimecast.com include:spf.protection.outlook.com -all
- pexip-ms-tenant-domain-verification=1ebc4d57-0fa1-4fdf-b0d0-2ee49c2e399b
- dgp5lej5s619j1r07hhe0l2u4g.
- grtb4os1s84832b1ubetnnn731
- duo_sso_verification=POlMud9HKEQlukqWyYevVadDCFKeOUIJCUs9rzcCGjsf4W9yvxluV6P69nETX8UU
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