DNS Relay | Hard Code DNS Servers | Pros | Cons |
Enabled | Yes | Clients receive fixed local DNS server. Router can immediately proxy dns queries. | DNS servers may become out-of-date. |
Enabled | No | Clients receive fixed local DNS server. Router receives update-to-date DNS entries. | Some small delay in proxying queries. May delay troubleshooting. |
Disabled | Yes | Clients receive fixed DNS servers. | DNS queries become part of standard traffic and are inspected by the SPI engine. |
Disabled | No | Clients receive ISP's update-to-date dns server entries if known. | During periods when the WAN link is down, clients recieve DHCP leases without any dns servers. |