feat: limit incoming connections to lodestar (#5860)

* feat: limit incoming connections to lodestar * chore: revise comment
ChainSafe · Aug 12, 2023 · f1a2291 · f1a2291
1 parent 3c7b815
commit f1a2291
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/packages/beacon-node/src/network/libp2p/index.ts b/packages/beacon-node/src/network/libp2p/index.ts
@@ -75,6 +75,10 @@ export async function createNodeJsLibp2p(
     transports: [
       tcp({
         maxConnections: networkOpts.maxPeers,
+        // socket option: the maximum length of the queue of pending connections
+        // https://nodejs.org/dist/latest-v18.x/docs/api/net.html#serverlisten
+        // it's not safe if we increase this number
+        backlog: 5,
         closeServerOnMaxConnections: {
           closeAbove: networkOpts.maxPeers ?? Infinity,
           listenBelow: networkOpts.maxPeers ?? Infinity,
@@ -101,6 +105,9 @@ export async function createNodeJsLibp2p(
       //maxConnections: options.maxConnections,
       // DOCS: There is no way to turn off autodial other than setting minConnections to 0
       minConnections: 0,
+      // the maximum number of pending connections libp2p will accept before it starts rejecting incoming connections.
+      // make it the same to backlog option above
+      maxIncomingPendingConnections: 5,
     },
     datastore,
     services: {