Remove blocking CollectNow commands to fix heartbeat stability

Eliminates automatic CollectNow command sending on host connection which
was blocking the main message processing loop for up to 5 seconds per
command. Since agents transmit cached data every 2 seconds anyway, the
CollectNow optimization provided minimal benefit while causing heartbeat
detection issues. Also removes unused send_command wrapper method.

This should completely resolve intermittent host connection dropping.

.gitea/workflows/release.yml

@@ -113,13 +113,13 @@ jobs:
           NIX_HASH="sha256-$(python3 -c "import base64, binascii; print(base64.b64encode(binascii.unhexlify('$NEW_HASH')).decode())")"
           
           # Update the NixOS configuration
-          sed -i "s|version = \"v[^\"]*\"|version = \"$VERSION\"|" hosts/common/cm-dashboard.nix
-          sed -i "s|sha256 = \"sha256-[^\"]*\"|sha256 = \"$NIX_HASH\"|" hosts/common/cm-dashboard.nix
+          sed -i "s|version = \"v[^\"]*\"|version = \"$VERSION\"|" hosts/services/cm-dashboard.nix
+          sed -i "s|sha256 = \"sha256-[^\"]*\"|sha256 = \"$NIX_HASH\"|" hosts/services/cm-dashboard.nix
           
           # Commit and push changes
           git config user.name "Gitea Actions"
           git config user.email "actions@gitea.cmtec.se"
-          git add hosts/common/cm-dashboard.nix
+          git add hosts/services/cm-dashboard.nix
           git commit -m "Auto-update cm-dashboard to $VERSION
 
           - Update version to $VERSION with automated release

CLAUDE.md

@@ -115,7 +115,7 @@ This automatically:
 - Uploads binaries via Gitea API
 
 ### NixOS Configuration Updates
-Edit `~/projects/nixosbox/hosts/common/cm-dashboard.nix`:
+Edit `~/projects/nixosbox/hosts/services/cm-dashboard.nix`:
 
 ```nix
 version = "v0.1.X";

Cargo.lock

@@ -270,7 +270,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.64"
+version = "0.1.72"
 dependencies = [
  "anyhow",
  "chrono",
@@ -292,7 +292,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.64"
+version = "0.1.72"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -315,7 +315,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.64"
+version = "0.1.72"
 dependencies = [
  "chrono",
  "serde",

README.md

@@ -329,7 +329,7 @@ This triggers automated:
 - Tarball upload to Gitea
 
 ### NixOS Integration
-Update `~/projects/nixosbox/hosts/common/cm-dashboard.nix`:
+Update `~/projects/nixosbox/hosts/services/cm-dashboard.nix`:
 
 ```nix
 version = "v0.1.43";

agent/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard-agent"
-version = "0.1.65"
+version = "0.1.73"
 edition = "2021"
 
 [dependencies]

agent/src/agent.rs

@@ -351,36 +351,40 @@ impl Agent {
             _ => {}
         }
 
-        let output = tokio::process::Command::new("sudo")
-            .arg("systemctl")
-            .arg(action_str)
-            .arg(format!("{}.service", service_name))
-            .output()
-            .await?;
+        // Spawn the systemctl command asynchronously to avoid blocking the agent
+        let service_name_clone = service_name.to_string();
+        let action_str_clone = action_str.to_string();
         
+        tokio::spawn(async move {
+            let result = tokio::process::Command::new("sudo")
+                .arg("systemctl")
+                .arg(&action_str_clone)
+                .arg(format!("{}.service", service_name_clone))
+                .output()
+                .await;
+
+            match result {
+                Ok(output) => {
                     if output.status.success() {
-            info!("Service {} {} completed successfully", service_name, action_str);
+                        info!("Service {} {} completed successfully", service_name_clone, action_str_clone);
                         if !output.stdout.is_empty() {
                             debug!("stdout: {}", String::from_utf8_lossy(&output.stdout));
                         }
-            
-            // Note: User-stopped flag will be cleared by systemd collector 
-            // when service actually reaches 'active' state, not here
                     } else {
                         let stderr = String::from_utf8_lossy(&output.stderr);
-            error!("Service {} {} failed: {}", service_name, action_str, stderr);
-            return Err(anyhow::anyhow!("systemctl {} {} failed: {}", action_str, service_name, stderr));
+                        error!("Service {} {} failed: {}", service_name_clone, action_str_clone, stderr);
                     }
+                }
+                Err(e) => {
+                    error!("Failed to execute systemctl {} {}: {}", action_str_clone, service_name_clone, e);
+                }
+            }
+        });
 
-        // Force refresh metrics after service control to update service status
-        if matches!(action, ServiceAction::Start | ServiceAction::Stop | ServiceAction::UserStart | ServiceAction::UserStop) {
-            info!("Triggering immediate metric refresh after service control");
-            if let Err(e) = self.collect_metrics_only().await {
-                error!("Failed to refresh metrics after service control: {}", e);
-            } else {
-                info!("Service status refreshed immediately after {} {}", action_str, service_name);
-            }
-        }
+        info!("Service {} {} command initiated (non-blocking)", service_name, action_str);
+
+        // Note: Service status will be updated by the normal metric collection cycle
+        // once the systemctl operation completes
 
         Ok(())
     }

agent/src/config/mod.rs

@@ -150,6 +150,9 @@ pub struct NotificationConfig {
     /// List of metric names to exclude from email notifications
     #[serde(default)]
     pub exclude_email_metrics: Vec<String>,
+    /// Path to maintenance mode file that suppresses email notifications when present
+    #[serde(default = "default_maintenance_mode_file")]
+    pub maintenance_mode_file: String,
 }
 
 
@@ -157,6 +160,10 @@ fn default_heartbeat_interval_seconds() -> u64 {
     5
 }
 
+fn default_maintenance_mode_file() -> String {
+    "/tmp/cm-maintenance".to_string()
+}
+
 impl AgentConfig {
     pub fn from_file<P: AsRef<Path>>(path: P) -> Result<Self> {
         loader::load_config(path)

agent/src/notifications/mod.rs

@@ -59,6 +59,6 @@ impl NotificationManager {
     }
 
     fn is_maintenance_mode(&self) -> bool {
-        std::fs::metadata("/tmp/cm-maintenance").is_ok()
+        std::fs::metadata(&self.config.maintenance_mode_file).is_ok()
     }
 }

dashboard/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard"
-version = "0.1.65"
+version = "0.1.73"
 edition = "2021"
 
 [dependencies]

dashboard/src/app.rs

@@ -67,11 +67,8 @@ impl Dashboard {
             }
         };
 
-        // Connect to configured hosts from configuration
-        let hosts: Vec<String> = config.hosts.keys().cloned().collect();
-
         // Try to connect to hosts but don't fail if none are available
-        match zmq_consumer.connect_to_predefined_hosts(&hosts).await {
+        match zmq_consumer.connect_to_predefined_hosts(&config.hosts).await {
             Ok(_) => info!("Successfully connected to ZMQ hosts"),
             Err(e) => {
                 warn!(
@@ -137,12 +134,6 @@ impl Dashboard {
         })
     }
 
-    /// Send a command to a specific agent
-    pub async fn send_command(&mut self, hostname: &str, command: AgentCommand) -> Result<()> {
-        self.zmq_command_sender
-            .send_command(hostname, command)
-            .await
-    }
 
     pub async fn run(&mut self) -> Result<()> {
         info!("Starting dashboard main loop");
@@ -215,35 +206,19 @@ impl Dashboard {
                         metric_message.metrics.len()
                     );
 
-                    // Check if this is the first time we've seen this host
+                    // Track first contact with host (no command needed - agent sends data every 2s)
                     let is_new_host = !self
                         .initial_commands_sent
                         .contains(&metric_message.hostname);
 
                     if is_new_host {
                         info!(
-                            "First contact with host {}, sending initial CollectNow command",
-                            metric_message.hostname
-                        );
-
-                        // Send CollectNow command for immediate refresh
-                        if let Err(e) = self
-                            .send_command(&metric_message.hostname, AgentCommand::CollectNow)
-                            .await
-                        {
-                            error!(
-                                "Failed to send initial CollectNow command to {}: {}",
-                                metric_message.hostname, e
-                            );
-                        } else {
-                            info!(
-                                "✓ Sent initial CollectNow command to {}",
+                            "First contact with host {} - data will update automatically",
                             metric_message.hostname
                         );
                         self.initial_commands_sent
                             .insert(metric_message.hostname.clone());
                     }
-                    }
 
                     // Update metric store
                     self.metric_store

dashboard/src/communication/mod.rs

@@ -84,13 +84,14 @@ impl ZmqConsumer {
         }
     }
 
-    /// Connect to predefined hosts
-    pub async fn connect_to_predefined_hosts(&mut self, hosts: &[String]) -> Result<()> {
+
+    /// Connect to predefined hosts using their configuration
+    pub async fn connect_to_predefined_hosts(&mut self, hosts: &std::collections::HashMap<String, crate::config::HostDetails>) -> Result<()> {
         let default_port = self.config.subscriber_ports[0];
 
-        for hostname in hosts {
-            // Try to connect, but don't fail if some hosts are unreachable
-            if let Err(e) = self.connect_to_host(hostname, default_port).await {
+        for (hostname, host_details) in hosts {
+            // Try to connect using configured IP, but don't fail if some hosts are unreachable
+            if let Err(e) = self.connect_to_host_with_details(hostname, host_details, default_port).await {
                 warn!("Could not connect to {}: {}", hostname, e);
             }
         }
@@ -104,6 +105,15 @@ impl ZmqConsumer {
         Ok(())
     }
 
+    /// Connect to a host using its configuration details
+    pub async fn connect_to_host_with_details(&mut self, hostname: &str, host_details: &crate::config::HostDetails, port: u16) -> Result<()> {
+        // Get primary connection IP only - no fallbacks
+        let primary_ip = host_details.get_connection_ip(hostname);
+        
+        // Connect directly without fallback attempts
+        self.connect_to_host(&primary_ip, port).await
+    }
+
     /// Receive command output from any connected agent (non-blocking)  
     pub async fn receive_command_output(&mut self) -> Result<Option<CommandOutputMessage>> {
         match self.subscriber.recv_bytes(zmq::DONTWAIT) {

dashboard/src/config/mod.rs

@@ -29,6 +29,17 @@ fn default_heartbeat_timeout_seconds() -> u64 {
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct HostDetails {
     pub mac_address: Option<String>,
+    /// Primary IP address (local network)
+    pub ip: Option<String>,
+}
+
+
+impl HostDetails {
+    /// Get the IP address for connection (uses ip field or hostname as fallback)
+    pub fn get_connection_ip(&self, hostname: &str) -> String {
+        self.ip.as_ref().unwrap_or(&hostname.to_string()).clone()
+    }
+
 }
 
 /// System configuration

dashboard/src/ui/mod.rs

@@ -251,12 +251,14 @@ impl TuiApp {
                 KeyCode::Char('r') => {
                     // System rebuild command - works on any panel for current host
                     if let Some(hostname) = self.current_host.clone() {
+                        let connection_ip = self.get_connection_ip(&hostname);
                         // Create command that shows logo, rebuilds, and waits for user input
                         let logo_and_rebuild = format!(
-                            "bash -c 'cat << \"EOF\"\nNixOS System Rebuild\nTarget: {}\n\nEOF\nssh -tt {}@{} \"bash -ic {}\"\necho\necho \"========================================\"\necho \"Rebuild completed. Press any key to close...\"\necho \"========================================\"\nread -n 1 -s\nexit'",
+                            "bash -c 'cat << \"EOF\"\nNixOS System Rebuild\nTarget: {} ({})\n\nEOF\nssh -tt {}@{} \"bash -ic {}\"\necho\necho \"========================================\"\necho \"Rebuild completed. Press any key to close...\"\necho \"========================================\"\nread -n 1 -s\nexit'",
                             hostname,
+                            connection_ip,
                             self.config.ssh.rebuild_user,
-                            hostname,
+                            connection_ip,
                             self.config.ssh.rebuild_alias
                         );
                         
@@ -289,10 +291,11 @@ impl TuiApp {
                 KeyCode::Char('J') => {
                     // Show service logs via journalctl in tmux split window
                     if let (Some(service_name), Some(hostname)) = (self.get_selected_service(), self.current_host.clone()) {
+                        let connection_ip = self.get_connection_ip(&hostname);
                         let journalctl_command = format!(
                             "bash -c \"ssh -tt {}@{} 'sudo journalctl -u {}.service -f --no-pager -n 50'; exit\"",
                             self.config.ssh.rebuild_user,
-                            hostname,
+                            connection_ip,
                             service_name
                         );
                         
@@ -312,10 +315,11 @@ impl TuiApp {
                         // Check if this service has a custom log file configured
                         if let Some(host_logs) = self.config.service_logs.get(&hostname) {
                             if let Some(log_config) = host_logs.iter().find(|config| config.service_name == service_name) {
+                                let connection_ip = self.get_connection_ip(&hostname);
                                 let tail_command = format!(
                                     "bash -c \"ssh -tt {}@{} 'sudo tail -n 50 -f {}'; exit\"",
                                     self.config.ssh.rebuild_user,
-                                    hostname,
+                                    connection_ip,
                                     log_config.log_file_path
                                 );
                                 
@@ -368,10 +372,11 @@ impl TuiApp {
                 KeyCode::Char('t') => {
                     // Open SSH terminal session in tmux window
                     if let Some(hostname) = self.current_host.clone() {
+                        let connection_ip = self.get_connection_ip(&hostname);
                         let ssh_command = format!(
                             "ssh -tt {}@{}",
                             self.config.ssh.rebuild_user,
-                            hostname
+                            connection_ip
                         );
                         
                         std::process::Command::new("tmux")
@@ -824,8 +829,10 @@ impl TuiApp {
                 let host_widgets = self.get_or_create_host_widgets(&hostname);
                 host_widgets.system_scroll_offset
             };
+            // Clone the config to avoid borrowing issues
+            let config = self.config.clone();
             let host_widgets = self.get_or_create_host_widgets(&hostname);
-            host_widgets.system_widget.render_with_scroll(frame, inner_area, scroll_offset, &hostname);
+            host_widgets.system_widget.render_with_scroll(frame, inner_area, scroll_offset, &hostname, Some(&config));
         }
     }
 
@@ -917,6 +924,15 @@ impl TuiApp {
     }
 
     /// Parse MAC address string (e.g., "AA:BB:CC:DD:EE:FF") to [u8; 6]
+    /// Get the connection IP for a hostname based on host configuration
+    fn get_connection_ip(&self, hostname: &str) -> String {
+        if let Some(host_details) = self.config.hosts.get(hostname) {
+            host_details.get_connection_ip(hostname)
+        } else {
+            hostname.to_string()
+        }
+    }
+
     fn parse_mac_address(mac_str: &str) -> Result<[u8; 6], &'static str> {
         let parts: Vec<&str> = mac_str.split(':').collect();
         if parts.len() != 6 {

dashboard/src/ui/widgets/system.rs

@@ -439,7 +439,7 @@ impl Widget for SystemWidget {
 
 impl SystemWidget {
     /// Render with scroll offset support
-    pub fn render_with_scroll(&mut self, frame: &mut Frame, area: Rect, scroll_offset: usize, hostname: &str) {
+    pub fn render_with_scroll(&mut self, frame: &mut Frame, area: Rect, scroll_offset: usize, hostname: &str, config: Option<&crate::config::DashboardConfig>) {
         let mut lines = Vec::new();
 
         // NixOS section
@@ -457,6 +457,16 @@ impl SystemWidget {
             Span::styled(format!("Agent: {}", agent_version_text), Typography::secondary())
         ]));
         
+        // Display detected connection IP
+        if let Some(config) = config {
+            if let Some(host_details) = config.hosts.get(hostname) {
+                let detected_ip = host_details.get_connection_ip(hostname);
+                lines.push(Line::from(vec![
+                    Span::styled(format!("IP: {}", detected_ip), Typography::secondary())
+                ]));
+            }
+        }
+        
 
         // CPU section
         lines.push(Line::from(vec![

shared/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-dashboard-shared"
-version = "0.1.65"
+version = "0.1.73"
 edition = "2021"
 
 [dependencies]