Add flag to disable warning logs for duplicate gossip messages (#5009)

* Add flag to disable warning logs for duplicate gossip messages.

* Update Lighthouse book.

beacon_node/lighthouse_network/src/config.rs

@@ -158,6 +158,10 @@ pub struct Config {
 
     /// Configuration for the inbound rate limiter (requests received by this node).
     pub inbound_rate_limiter_config: Option<InboundRateLimiterConfig>,
+
+    /// Whether to disable logging duplicate gossip messages as WARN. If set to true, duplicate  
+    /// errors will be logged at DEBUG level.
+    pub disable_duplicate_warn_logs: bool,
 }
 
 impl Config {
@@ -375,6 +379,7 @@ impl Default for Config {
             outbound_rate_limiter_config: None,
             invalid_block_storage: None,
             inbound_rate_limiter_config: None,
+            disable_duplicate_warn_logs: false,
         }
     }
 }

beacon_node/lighthouse_network/src/service/mod.rs

@@ -128,6 +128,8 @@ pub struct Network<AppReqId: ReqId, TSpec: EthSpec> {
     gossip_cache: GossipCache,
     /// This node's PeerId.
     pub local_peer_id: PeerId,
+    /// Flag to disable warning logs for duplicate gossip messages and log at DEBUG level instead.
+    pub disable_duplicate_warn_logs: bool,
     /// Logger for behaviour actions.
     log: slog::Logger,
 }
@@ -425,6 +427,7 @@ impl<AppReqId: ReqId, TSpec: EthSpec> Network<AppReqId, TSpec> {
             update_gossipsub_scores,
             gossip_cache,
             local_peer_id,
+            disable_duplicate_warn_logs: config.disable_duplicate_warn_logs,
             log,
         };
 
@@ -743,7 +746,21 @@ impl<AppReqId: ReqId, TSpec: EthSpec> Network<AppReqId, TSpec> {
                     .gossipsub_mut()
                     .publish(Topic::from(topic.clone()), message_data.clone())
                 {
-                    slog::warn!(self.log, "Could not publish message"; "error" => ?e);
+                    if self.disable_duplicate_warn_logs && matches!(e, PublishError::Duplicate) {
+                        debug!(
+                            self.log,
+                            "Could not publish message";
+                            "error" => ?e,
+                            "kind" => %topic.kind(),
+                        );
+                    } else {
+                        warn!(
+                            self.log,
+                            "Could not publish message";
+                            "error" => ?e,
+                            "kind" => %topic.kind(),
+                        );
+                    };
 
                     // add to metrics
                     match topic.kind() {

beacon_node/src/cli.rs

@@ -1288,5 +1288,15 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                 .default_value("64")
                 .takes_value(true)
         )
+        .arg(
+            Arg::with_name("disable-duplicate-warn-logs")
+                .long("disable-duplicate-warn-logs")
+                .help("Disable warning logs for duplicate gossip messages. The WARN level log is \
+                    useful for detecting a duplicate validator key running elsewhere. However, this may \
+                    result in excessive warning logs if the validator is broadcasting messages to \
+                    multiple beacon nodes via the validator client --broadcast flag. In this case, \
+                    disabling these warn logs may be useful.")
+                .takes_value(false)
+        )
         .group(ArgGroup::with_name("enable_http").args(&["http", "gui", "staking"]).multiple(true))
 }

beacon_node/src/config.rs

@@ -1395,6 +1395,9 @@ pub fn set_network_config(
             Some(config_str.parse()?)
         }
     };
+
+    config.disable_duplicate_warn_logs = cli_args.is_present("disable-duplicate-warn-logs");
+
     Ok(())
 }