WS-7640
Cisco WS-7640 DNS Resolution Error
Cisco
DNS Resolution Error
ASA
91% fix rate
Cause
DNSSEC validation failure for requested domain
Fix Steps
- Open router admin panel and navigate to DNS settings
- Change primary DNS to 8.8.8.8 (Google) or 1.1.1.1 (Cloudflare)
- Set secondary DNS to 8.8.4.4 or 1.0.0.1
- Flush DNS cache: ipconfig /flushdns (Windows) or sudo dscacheutil -flushcache (Mac)
- Restart router and connected devices
- Test DNS resolution: nslookup google.com