diff --git a/docker-compose.yml b/docker-compose.yml
index 7a0d155..d02cf5c 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -61,9 +61,6 @@ services:
       - "4001:4001/udp"
       - "${IPFS_GATEWAY_BIND:-127.0.0.1}:8080:8080"
     networks: [mynet]
-    sysctls:
-      net.core.rmem_max: "2500000"
-      net.core.wmem_max: "2500000"
     ulimits:
       nofile: { soft: 65536, hard: 65536 }
 
diff --git a/start.sh b/start.sh
index abaa6da..0e528cd 100644
--- a/start.sh
+++ b/start.sh
@@ -36,17 +36,31 @@ fi
 ask_or_keep() {
   local key="$1"; shift
   local prompt="$1"; shift
-  local def="$1"; shift || true
+  local def=""
+  if [[ $# -gt 0 ]]; then
+    def="$1"
+    shift
+  fi
+  local invalid=""
+  if [[ $# -gt 0 ]]; then
+    invalid="$1"
+    shift
+  fi
   local cur
   cur=$(ini_val "$key")
-  if [[ -n "$cur" ]]; then
+  if [[ -n "$cur" && ( -z "$invalid" || "$cur" != "$invalid" ) ]]; then
     echo "$key is set in .env; keeping existing value"
     eval "$key=\"$cur\""
-  else
-    read -rp "$prompt [${def}]: " val || true
-    val=${val:-$def}
-    eval "$key=\"$val\""
+    return
   fi
+  local hint="$def"
+  if [[ -n "$hint" ]]; then
+    read -rp "$prompt [${hint}]: " val || true
+    val=${val:-$hint}
+  else
+    read -rp "$prompt: " val || true
+  fi
+  eval "$key=\"$val\""
 }
 
 if [[ "$NODE_PRIVACY" == "private" ]]; then
@@ -58,10 +72,10 @@ fi
 
 ask_or_keep SANIC_PORT "Internal app port (SANIC_PORT)" "$(ini_val SANIC_PORT)"
 ask_or_keep BACKEND_HTTP_PORT "Published backend port on host (BACKEND_HTTP_PORT)" "$(ini_val BACKEND_HTTP_PORT)"
-ask_or_keep BOOTSTRAP_SEEDS "Bootstrap seeds (comma-separated URLs)" "$(ini_val BOOTSTRAP_SEEDS)"
+ask_or_keep BOOTSTRAP_SEEDS "Bootstrap seeds (comma-separated URLs)" "" "https://my-bootstrap-1.example.com,https://my-bootstrap-2.example.com"
 ask_or_keep HANDSHAKE_INTERVAL_SEC "Handshake interval seconds" "$(ini_val HANDSHAKE_INTERVAL_SEC)"
-ask_or_keep TELEGRAM_API_KEY "Telegram uploader bot token (TELEGRAM_API_KEY)" "$(ini_val TELEGRAM_API_KEY)"
-ask_or_keep CLIENT_TELEGRAM_API_KEY "Telegram client bot token (CLIENT_TELEGRAM_API_KEY)" "$(ini_val CLIENT_TELEGRAM_API_KEY)"
+ask_or_keep TELEGRAM_API_KEY "Telegram uploader bot token (TELEGRAM_API_KEY)" "" "YOUR_UPLOADER_BOT_TOKEN"
+ask_or_keep CLIENT_TELEGRAM_API_KEY "Telegram client bot token (CLIENT_TELEGRAM_API_KEY)" "" "YOUR_CLIENT_BOT_TOKEN"
 
 echo "Applying configuration to $ENV_FILE ..."
 
@@ -83,7 +97,24 @@ fi
 update_env SANIC_PORT "$SANIC_PORT"
 update_env BACKEND_HTTP_PORT "$BACKEND_HTTP_PORT"
 update_env BOOTSTRAP_SEEDS "$BOOTSTRAP_SEEDS"
+local local_bootstrap_required=$(ini_val BOOTSTRAP_REQUIRED)
+if [[ -z "$BOOTSTRAP_SEEDS" ]]; then
+  echo "No bootstrap seeds provided; disabling mandatory bootstrap."
+  update_env BOOTSTRAP_REQUIRED 0
+else
+  local_bootstrap_required=${local_bootstrap_required:-1}
+  update_env BOOTSTRAP_REQUIRED "$local_bootstrap_required"
+fi
 update_env HANDSHAKE_INTERVAL_SEC "$HANDSHAKE_INTERVAL_SEC"
+if [[ -z "$TELEGRAM_API_KEY" || "$TELEGRAM_API_KEY" == "YOUR_UPLOADER_BOT_TOKEN" ]]; then
+  echo "TELEGRAM_API_KEY must be provided (create a bot via @BotFather)." >&2
+  exit 1
+fi
+if [[ -z "$CLIENT_TELEGRAM_API_KEY" || "$CLIENT_TELEGRAM_API_KEY" == "YOUR_CLIENT_BOT_TOKEN" ]]; then
+  echo "CLIENT_TELEGRAM_API_KEY must be provided (client bot token)." >&2
+  exit 1
+fi
+
 update_env TELEGRAM_API_KEY "$TELEGRAM_API_KEY"
 update_env CLIENT_TELEGRAM_API_KEY "$CLIENT_TELEGRAM_API_KEY"