🌐DNS
2 A · 2 MX · 3 NS · 8 CAA · 2 PTR · 1 SOA · 3 TXT · 2 AAAA
🔒SSL/TLS
GlobalSign nv-sa · TLSv1.2 · expires in 191d · 2 SANs
✉️Email Auth
SPF ✗ · DKIM ✗ · DMARC ✗
🔐DNSSEC
signed · valid chain of trust
💻Tech Stack
Host: China Education and Research Network Center · Email: Self-hosted · nginx
📡HTTP
HTTP 200 · HSTS ✗ · CSP ✗ · X-Frame ✓ · Nosniff ✗
🛡️Security
B (163/215) · 2 critical · 1 high
📈Deliverability
B (80/100) · 2 MX · 2 IPs · 4 issue(s)
🔍Subdomains
8 found · 112 answered — imap, m, mail, pop, pop3, smtp +2 more
📚Web Archive
no snapshots found