WDY-570: Enable systemd-resolved for container DNS#43
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mihai-chiorean wants to merge 2 commits intomainfrom
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WDY-570: Enable systemd-resolved for container DNS#43mihai-chiorean wants to merge 2 commits intomainfrom
mihai-chiorean wants to merge 2 commits intomainfrom
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Resolves EDG-295 **Problem:** When macOS Internet Connection Sharing (ICS) is enabled, both the Mac and EdgeOS device try to run DHCP servers on the USB interface, causing: - DHCP conflicts and network failures - Only IPv6 connectivity after toggling ICS - Unpredictable behavior when ICS is disabled/re-enabled **Solution:** Replace the device's DHCP server with a DHCP client + link-local fallback: - **DHCP client mode:** Accepts IP from Mac ICS when available - **Link-local fallback:** Auto-configures 169.254.x.x when no DHCP server - **IPv6 link-local:** Always available (fe80::...) **Benefits:** 1. **Works with Mac ICS enabled:** - Device gets DHCP address (192.168.2.x from Mac) - Internet sharing works through Mac - Proper DNS and routing 2. **Works with Mac ICS disabled:** - Both host and device auto-configure link-local - Connection still works via 169.254.x.x - No DHCP timeouts or delays 3. **Works with mDNS:** - Device always accessible via edgeos-<uuid>.local - Link-local addresses advertised via mDNS - Works on both IPv4 and IPv6 **Testing:** - ✅ Mac ICS enabled: Device gets 192.168.2.6, internet works - ✅ Mac ICS disabled: Both use link-local, SSH works - ✅ IPv6 link-local: Always accessible via fe80::...%interface - ✅ mDNS discovery: Works in all configurations
Container DNS was broken because /etc/resolv.conf pointed to 127.0.0.53 (systemd-resolved stub), which doesn't work in containers. This enables systemd-resolved and configures it to create /run/systemd/resolve/resolv.conf with actual upstream DNS servers. **Changes:** - Enable 'resolved' in systemd PACKAGECONFIG (alongside existing networkd) - Auto-enable systemd-resolved.service at boot - Configure resolved with fallback DNS (8.8.8.8, 1.1.1.1) - Disable LLMNR (not needed) - Enable MulticastDNS for .local domains (Avahi compatibility) **How it works:** 1. systemd-resolved runs and listens on 127.0.0.53 2. Creates /run/systemd/resolve/resolv.conf with real DNS servers 3. wendy-agent mounts this file into containers (from PR #173) 4. Containers get working DNS without stub resolver issues **Benefits:** - Containers can resolve DNS properly - Works with modern systemd-resolved systems - Fallback DNS ensures reliability - Compatible with existing mDNS/Avahi setup Related: WDY-570
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Summary
This PR enables systemd-resolved on WendyOS to support proper DNS resolution in containers created by wendy-agent.
Problem
Containers need access to upstream DNS servers, but
/etc/resolv.conftypically points to systemd-resolved's stub resolver at 127.0.0.53, which doesn't work inside containers.Solution
Enable and configure systemd-resolved to create
/run/systemd/resolve/resolv.conf, which contains actual upstream DNS servers that containers can use.Changes
systemd Recipe Configuration
resolvedto PACKAGECONFIG alongsidenetworkdFiles Added
/etc/systemd/system/multi-user.target.wants/systemd-resolved.service- Service enablement/etc/systemd/resolved.conf.d/10-edgeos.conf- DNS configurationHow It Works
/run/systemd/resolve/resolv.confRelated Changes
This complements the wendy-agent changes in wendylabsinc/wendy-agent#173 which mount
/run/systemd/resolve/resolv.confinto containers.Testing
After deploying WendyOS with this change:
systemctl status systemd-resolved/run/systemd/resolve/resolv.confexists and contains real DNS servers