Domain Overview
DNS: ✓ 6h ago
Checker: ✓ 6h ago
rtc.edu
Yes
✓ Yes
Barracuda
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-05-20 23:44:04 UTC · ↺ Refresh
MX Hostnames
- d340177b.ess.barracudanetworks.com
- d340177a.ess.barracudanetworks.com
MX Priorities
- d340177b.ess.barracudanetworks.com: 10
- d340177a.ess.barracudanetworks.com: 0
A / AAAA Records
- 192.124.249.110 ↩ cloudproxy10110.sucuri.net
Mail Server IPs
- 209.222.82.255 ↩ mail.ess.barracuda.com
- 209.222.82.252 ↩ mail.ess.barracuda.com
- 209.222.82.253 ↩ mail.ess.barracuda.com
SOA Record
Raw SOA
ns-1551.awsdns-01.co.uk awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-1551.awsdns-01.co.uk
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-1551.awsdns-01.co.uk
ns-461.awsdns-57.com
ns-675.awsdns-20.net
ns-1478.awsdns-56.org
SPF Record
✓ Soft Fail (~all)
v=spf1 ip4:192.64.1.146 ip4:134.39.27.208 ip4:168.156.21.170 ip4:168.156.9.200 ip4:168.156.16.2 include:sendgrid.net include:spf.protection.outlook.com include:amazonses.com include:spf.ess.barracudanetworks.com ~all
📊 DNS lookups: 4/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
~ Quarantine
v=DMARC1;p=quarantine;pct=0;adkim=r;aspf=r;rua=mailto:[email protected],mailto:[email protected];ruf=mailto:[email protected],mailto:[email protected];fo=1
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected],mailto:[email protected]
⚠ Policy applies to 0% of failing messages only
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._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
16 records- adobe-sign-verification=a489096576229045762ed293c2f1ade7
- apple-domain-verification=hy3Fihi4EryTKLXW
- csmhreft8f99fuhgf1rhpid6ui
- google-site-verification=C134SSWdyjzTPeeteRoIGPQLYgwOBR48f1FuOmihvSA
- i4d0eaessitpogt8v8gsq33tnv
- mpandu011801irs5tsvc9og0ds
- mtonfcqm7uvjq50n241ri3bjgq
- qep9crifikr7me8jc2qhekqt3d
- thvnlh3mog86t9so9r7rhspljq
- urc05fv9ph768p4dltjlojoocm
- SPFv=spf1 ip4:192.64.1.146 ip4:134.39.27.208 ip4:168.156.21.170 ip4:168.156.9.200 ip4:168.156.16.2 include:sendgrid.net include:spf.protection.outlook.com include:amazonses.com include:spf.ess.barracudanetworks.com ~all
- 3t938jsf7b63plqmppq3dnbq7h
- MS=ms58030735
- OkpqejfF9fy+FWZUPGVUQqpQ+j/K+wsVDmwarNgy+lUX1MGPknT5t/u8UV+1Hc+B1atZhoMNdlVSXbUz62lyPA==
- adobe-idp-site-verification=96063d4304393aae47b714a219a4c07ff0b4acb03141a0e0fc3e0b9d5c15648c
- adobe-idp-site-verification=de3cbb97-f8ec-4403-8071-cddd037c6dd7
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