COREDNS-HTTPS3(7)

🌈 NAME 🌈

okay so this is the COREDNS-HTTPS3(7) page from the CoreDNS Plugins manual, and it's all about the https3 plugin — the one that configures DNS-over-HTTPS/3 (DoH3) server options. iykyk 💅

---

💅 DESCRIPTION 💅

the https3 plugin lets you configure parameters for the DNS-over-HTTPS/3 (DoH3) server so you can fine-tune the security posture and performance of the server. HTTPS/3 uses QUIC as the underlying transport — yes, QUIC is literally the main character here. 🦋

🫶 heads up, bestie: this plugin can only be used once per HTTPS3 listener block. one per block, no double-stacking. periodt.

---

✨ SYNTAX ✨

https3 {
    max_streams POSITIVE_INTEGER
    max_connections POSITIVE_INTEGER
}

• max_streams — caps the number of concurrent QUIC streams per connection. this helps prevent unbounded streams on a single connection from exhausting server resources. if you don't specify it, the default value is 256. set it to 0 to use the underlying QUIC transport default. 🎀
• max_connections — caps the number of concurrent HTTPS/3 connections accepted by the server. if you don't specify it, the default value is 200. connections above the configured limit are rejected. set it to 0 to disable the CoreDNS connection limit. 🫶

---

🔥 EXAMPLES 🔥

set custom limits for maximum streams:

https3://.:443 {
    tls cert.pem key.pem
    https3 {
        max_streams 50
    }
    whoami
}

set values to 0 for QUIC transport default, matching CoreDNS behaviour before v1.14.0:

https3://.:443 {
    tls cert.pem key.pem
    https3 {
        max_streams 0
    }
    whoami
}

---

mwah 💋 this has been COREDNS-HTTPS3(7) — source/version: CoreDNS, date: October 2026. go tune those DoH3 limits, bestie, and remember: one https3 block per HTTPS3 listener block. slay ✨👑