Fix/dns hosts configuration

scripts/device-agent.sh

@@ -115,6 +115,8 @@ source "${SCRIPT_DIR}/modules/harbor.sh"
 source "${SCRIPT_DIR}/modules/certificates.sh"
 source "${SCRIPT_DIR}/modules/agent.sh"
 source "${SCRIPT_DIR}/modules/observability.sh"
+source "${SCRIPT_DIR}/modules/dns-host-config.sh"
+
 
 
 export GOINSECURE='github.com/margo/*'
@@ -178,6 +180,8 @@ install_prerequisites() {
   if [ "$DEVICE_TYPE" = "k3s" ]; then
     setup_k3s
     configure_harbor_trust_for_k3s
+    sleep 5
+    configure_coredns_hosts
   fi
 
   echo 'prerequisites installation completed.'

scripts/modules/dns-host-config.sh

@@ -0,0 +1,154 @@
+#!/bin/bash
+
+#------------------------------------------------------------------------------
+# Returns the IPv4 address of the specified hostname from /etc/hosts.
+#------------------------------------------------------------------------------
+get_ip_from_hosts() {
+    local hostname="$1"
+    local hosts_file="/etc/hosts"
+    local ip
+
+    if [[ ! -r "$hosts_file" ]]; then
+        echo "[ERROR] Unable to read ${hosts_file}." >&2
+        return 1
+    fi
+
+    ip=$(
+        awk -v host="$hostname" '
+            /^[[:space:]]*#/ { next }
+            NF >= 2 && $2 == host {
+                print $1
+                exit
+            }
+        ' "$hosts_file"
+    )
+
+    if [[ -z "$ip" ]]; then
+        echo "[ERROR] Host '${hostname}' not found in ${hosts_file}." >&2
+        return 1
+    fi
+
+    if [[ ! "$ip" =~ ^([0-9]{1,3}\.){3}[0-9]{1,3}$ ]]; then
+        echo "[ERROR] Invalid IPv4 address '${ip}' for '${hostname}'." >&2
+        return 1
+    fi
+
+    printf '%s\n' "$ip"
+}
+
+#------------------------------------------------------------------------------
+# Adds or updates NodeHosts entries in the CoreDNS ConfigMap.
+#------------------------------------------------------------------------------
+configure_coredns_hosts() {
+    set -euo pipefail
+
+    local namespace="kube-system"
+    local configmap="coredns"
+
+    local harbor_host="harbor.machine"
+    local symphony_host="symphony.machine"
+
+    local harbor_ip
+    local symphony_ip
+
+    local nodehosts
+    local updated
+
+    echo "[INFO] Validating dependencies..."
+
+    for cmd in kubectl jq awk sed; do
+        if ! command -v "$cmd" >/dev/null 2>&1; then
+            echo "[ERROR] Required command '$cmd' is not installed." >&2
+            return 1
+        fi
+    done
+
+    echo "[INFO] Reading IP addresses from /etc/hosts..."
+
+    harbor_ip=$(get_ip_from_hosts "$harbor_host")
+    symphony_ip=$(get_ip_from_hosts "$symphony_host")
+
+    echo "[INFO] Verifying CoreDNS ConfigMap..."
+
+    if ! kubectl -n "$namespace" get configmap "$configmap" >/dev/null 2>&1; then
+        echo "[ERROR] ConfigMap '${configmap}' not found in namespace '${namespace}'." >&2
+        return 1
+    fi
+
+    nodehosts=$(
+        kubectl -n "$namespace" get configmap "$configmap" \
+            -o jsonpath='{.data.NodeHosts}' 2>/dev/null || true
+    )
+
+    updated="$nodehosts"
+
+    add_or_update_host() {
+        local ip="$1"
+        local host="$2"
+
+        if awk -v host="$host" '
+            /^[[:space:]]*#/ { next }
+            $2 == host { found=1 }
+            END { exit !found }
+        ' <<<"$updated"; then
+
+            updated=$(
+                awk -v ip="$ip" -v host="$host" '
+                    /^[[:space:]]*#/ {
+                        print
+                        next
+                    }
+
+                    $2 == host {
+                        print ip " " host
+                        next
+                    }
+
+                    {
+                        print
+                    }
+                ' <<<"$updated"
+            )
+
+        else
+            if [[ -n "$updated" ]]; then
+                updated+=$'\n'
+            fi
+            updated+="${ip} ${host}"
+        fi
+    }
+
+    add_or_update_host "$harbor_ip" "$harbor_host"
+    add_or_update_host "$symphony_ip" "$symphony_host"
+
+    updated=$(sed '/^[[:space:]]*$/d' <<<"$updated")
+
+    if [[ "$updated" == "$nodehosts" ]]; then
+        echo "[INFO] CoreDNS NodeHosts already up to date."
+        return 0
+    fi
+
+    echo "[INFO] Updating CoreDNS ConfigMap..."
+
+    kubectl -n "$namespace" patch configmap "$configmap" \
+        --type merge \
+        --patch "$(cat <<EOF
+{
+  "data": {
+    "NodeHosts": $(printf '%s' "$updated" | jq -Rs .)
+  }
+}
+EOF
+)"
+
+    echo "[INFO] Restarting CoreDNS..."
+
+    kubectl -n "$namespace" rollout restart deployment/coredns
+
+    echo "[INFO] Waiting for CoreDNS rollout to complete..."
+
+    kubectl -n "$namespace" rollout status deployment/coredns --timeout=180s
+
+    echo "[INFO] CoreDNS NodeHosts updated successfully."
+}
+