Update infrastructure/ipv6.md

infrastructure/acme.md

@@ -10,6 +10,18 @@ We agreed to use **ACME DNS-01 challenges** for issuing certificates for **both
 - Keep **low TTLs** (e.g., 60-120s) on both CNAME and TXT records to speed up renewals.
 - Restrict write access to the challenge zone to the ACME automation only.
 
+## Meetings
+- 05.08.2025: Bert-Jan Fikse, Tobias Schaller, Tobias Wüst, Tom Jampen (inital version)
+
+## Background
+The following article explains how DNS-01 challenges can be effectively used to issue Let's Encrypt certificates for servers with internal IP addresses:
+
+- https://lists.bfh.science/pipermail/bfh-linux-announce/2021-September/000134.html
+
+The following manpage explains important implementation details for correctly handling DNS-01 challenges:
+
+- https://sources.debian.org/src/open-infrastructure-service-tools/20250626-2/dehydrated/share/man/dehydrated-nsupdate.1.rst#L20
+
 ## Reference Design
 **Dedicated zone:**
 `_acme.digitalboard.ch`

infrastructure/ipv6.md

@@ -6,7 +6,7 @@ We agreed to setup dual stack by default as IPv6 is essential for modern IT infr
 ## Decisions
 - Use **Dual Stack** (IPv4 and IPv6 addresses)
 - Rely on **DNS names instead of raw IP addresses**
-- **Each school is responsible for its DNS records** and must them for IPv4/IPv6 (including CNAME records for ACME)
+- **Each school is responsible for its DNS records** and must manage them for IPv4/IPv6 (including CNAME records for ACME)
 - The Digitalboard provides an optional service (dynamic DNS zone for acme challenge responses) as described in the [ACME documentation](./acme.md)
 - The Digitalboard might act as a RIPE customer and provide a `/32` or `/48` IPv6 network for interested schools