Symptoms: DNS Resolution Taking 5+ Seconds Intermittently

• Users and applications report intermittent slowness loading pages and connecting to services.
• DNS lookups sometimes complete in under 50ms but other times take 5-10 seconds.
• The delay is consistent at approximately 5 seconds when it occurs, suggesting a timeout.
• Applications with short connection timeouts (2-3 seconds) fail entirely during slow episodes.
• The issue affects all hosts configured with the same DNS resolver settings.
• Hosts using a different DNS configuration (e.g., 8.8.8.8) do not experience the delay.
• The problem is intermittent but increasing in frequency over the past week.
• No DNS-related error messages in syslog, just slow resolution.