Why was the SSL VPN client not receiving DNS IP on USG FLEX H device?

Zyxel_Emily

Question:
Why was the SSL VPN client not receiving DNS IP on USG FLEX H device?

Answer:
The issue occurred when the DNS was set to “ZyWALL” or certain other combinations in the global DNS setup for SSL VPN. This configuration caused the SSL VPN client (e.g., OpenVPN or SecuExtender) to miss custom DNS settings. This behavior was identified as a bug. The fix will be included in the next official firmware release (version 1.39), scheduled for release around July 2026.