DNS Chain Services

DNS Chain Services

Service Table

Service	Port	Role	Upstream
Pi-hole	53	Blocking, cache, DHCP	CoreDNS
CoreDNS	5352	Split-horizon, local zones	dnsdist
dnsdist	5330	Load balancer, Lua policy	Unbound, DNSCrypt
Unbound	5335	Recursive resolver	VPN DNS
Stubby	5360	DoT proxy (TLS)	VPN DNS
DNSCrypt	5354	DoH proxy	Cloudflare/Quad9 DoH
agentic-dns-server	853	DoT/mTLS proxy (Rust)	Chain entry

Service Definitions (from bin/agentic-dns)

SERVICES=(
    "pihole|53|${PIHOLE_HOST}|forwarder|coredns"
    "coredns|5352|127.0.0.1|split-horizon|dnsdist"
    "dnsdist|5330|127.0.0.1|loadbalancer|unbound,dnscrypt"
    "unbound|5335|127.0.0.1|resolver|vpn-dns"
    "stubby|5360|127.0.0.1|dot-proxy|vpn-dns|unbound"
    "dnscrypt|5354|127.0.0.1|doh-proxy|cloudflare-doh"
    "vpn-dns|53|${VPN_DNS:-unknown}|upstream|none"
)

Health Check Logic

is_listening() {
    # Checks `ss -tulnp` for port
    # VPN DNS tested via active dig query
}

dns_query() {
    timeout 5 dig +short "$domain" @"$addr" -p "$port"
}

get_service_status() {
    # Returns: up / unhealthy / down
}