Detect Ubuntu 24.04+ and disable apt-daily auto-updates at VC startup

VERSION

@@ -1 +1 @@
-3.1.2
+3.1.3

src/VirtualClient/VirtualClient.Main/ExecuteProfileCommand.cs

@@ -17,6 +17,7 @@ namespace VirtualClient
     using Microsoft.Extensions.DependencyInjection;
     using Microsoft.Extensions.Logging;
     using Newtonsoft.Json;
+    using VirtualClient.Common;
     using VirtualClient.Common.Contracts;
     using VirtualClient.Common.Extensions;
     using VirtualClient.Common.Telemetry;
@@ -163,6 +164,11 @@ protected override async Task<int> ExecuteAsync(string[] args, IServiceCollectio
 
                 logger.LogMessage($"Platform.Initialize", telemetryContext);
 
+                // Defend long-running workloads against unattended-upgrades triggered SIGKILL on
+                // Ubuntu 24.04+ (needrestart auto-restart-on-upgrade is enabled by default).
+                // Best-effort; never fails VC startup.
+                await this.DisableLinuxAutoUpdatesAsync(logger, systemManagement, telemetryContext, cancellationToken);
+
                 if (this.Profiles?.Any() == true)
                 {
                     this.LogContextToConsole(dependencies);
@@ -243,6 +249,94 @@ protected override async Task<int> ExecuteAsync(string[] args, IServiceCollectio
             return exitCode;
         }
 
+        /// <summary>
+        /// On Ubuntu 24.04 and later, the default installation of the
+        /// <see href="https://manpages.ubuntu.com/manpages/noble/man1/needrestart.1.html">needrestart</see>
+        /// package (combined with the <c>apt-daily-upgrade.timer</c> systemd timer that fires every day
+        /// between 06:00 and 07:00 UTC) will automatically restart services whose shared libraries are
+        /// updated by unattended upgrades. For long-running workloads this manifests as the Virtual Client
+        /// process being killed mid-run, desynchronizing multi-VM experiments and invalidating results.
+        /// <para>
+        /// This method is a best-effort mitigation that masks (and stops) the apt-daily timers and
+        /// services when running on Ubuntu 24.04 or newer. Failures are logged but never propagated
+        /// so that Virtual Client startup is unaffected.
+        /// </para>
+        /// </summary>
+        protected virtual async Task DisableLinuxAutoUpdatesAsync(
+            ILogger logger,
+            ISystemManagement systemManagement,
+            EventContext telemetryContext,
+            CancellationToken cancellationToken)
+        {
+            if (systemManagement == null || systemManagement.Platform != PlatformID.Unix)
+            {
+                return;
+            }
+
+            try
+            {
+                LinuxDistributionInfo distroInfo = await systemManagement.GetLinuxDistributionAsync(cancellationToken)
+                    .ConfigureAwait(false);
+
+                // The auto-restart-on-unattended-upgrade behavior has only been confirmed on Ubuntu 24.04+.
+                // Earlier Ubuntu releases and Debian do not auto-restart services in non-interactive mode
+                // and are not known to cause this issue in the field.
+                if (distroInfo?.LinuxDistribution != LinuxDistribution.Ubuntu
+                    || !ExecuteProfileCommand.TryGetUbuntuMajorVersion(distroInfo.OperationSystemFullName, out int majorVersion)
+                    || majorVersion < 24)
+                {
+                    return;
+                }
+
+                EventContext maskContext = telemetryContext.Clone()
+                    .AddContext("linuxDistribution", distroInfo.LinuxDistribution.ToString())
+                    .AddContext("linuxDistributionFullName", distroInfo.OperationSystemFullName)
+                    .AddContext("ubuntuMajorVersion", majorVersion);
+
+                // Double-quoted -c argument is required: .NET Process argument tokenization follows
+                // Windows CommandLineToArgvW-style rules (double-quote grouping only), so single quotes
+                // would be passed literally to bash.
+                string bashArgs = "-c \"systemctl mask apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service;"
+                    + " systemctl stop apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service;"
+                    + " exit 0\"";
+
+                using (IProcessProxy process = systemManagement.ProcessManager.CreateProcess("bash", bashArgs))
+                {
+                    await process.StartAndWaitAsync(cancellationToken).ConfigureAwait(false);
+                    maskContext.AddContext("exitCode", process.ExitCode);
+                    maskContext.AddContext("standardError", process.StandardError?.ToString());
+                }
+
+                logger.LogMessage($"{nameof(ExecuteProfileCommand)}.DisabledLinuxAutoUpdates", LogLevel.Information, maskContext);
+            }
+            catch (Exception exc)
+            {
+                // Never fail VC startup because of this mitigation.
+                logger.LogMessage(
+                    $"{nameof(ExecuteProfileCommand)}.DisableLinuxAutoUpdatesFailed",
+                    LogLevel.Warning,
+                    telemetryContext.Clone().AddError(exc));
+            }
+        }
+
+        /// <summary>
+        /// Parses the Ubuntu major version (e.g. 22, 24) from the PRETTY_NAME string returned
+        /// by <see cref="LinuxDistributionInfo.OperationSystemFullName"/> (e.g. "Ubuntu 24.04.1 LTS").
+        /// Returns false when the name does not contain a parseable Ubuntu version.
+        /// </summary>
+        internal static bool TryGetUbuntuMajorVersion(string osFullName, out int majorVersion)
+        {
+            majorVersion = 0;
+
+            if (string.IsNullOrWhiteSpace(osFullName))
+            {
+                return false;
+            }
+
+            Match match = Regex.Match(osFullName, @"Ubuntu\s+(\d+)\.", RegexOptions.IgnoreCase);
+            return match.Success && int.TryParse(match.Groups[1].Value, out majorVersion);
+        }
+
         /// <summary>
         /// Downloads the profile from a remote location to the local profile downloads folder.
         /// </summary>

src/VirtualClient/VirtualClient.Main/profiles/PERF-SPECCPU-FPRATE.json

@@ -41,14 +41,6 @@
         }
     ],
     "Dependencies": [
-        {
-            "Type": "ExecuteCommand",
-            "Parameters": {
-                "Scenario": "MaskAptDailyTimers",
-                "SupportedPlatforms": "linux-x64,linux-arm64",
-                "Command": "bash -c 'systemctl mask apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; systemctl stop apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; exit 0'"
-            }
-        },
         {
             "Type": "ChocolateyInstallation",
             "Parameters": {

src/VirtualClient/VirtualClient.Main/profiles/PERF-SPECCPU-FPSPEED.json

@@ -41,14 +41,6 @@
         }
     ],
     "Dependencies": [
-        {
-            "Type": "ExecuteCommand",
-            "Parameters": {
-                "Scenario": "MaskAptDailyTimers",
-                "SupportedPlatforms": "linux-x64,linux-arm64",
-                "Command": "bash -c 'systemctl mask apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; systemctl stop apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; exit 0'"
-            }
-        },
         {
             "Type": "ChocolateyInstallation",
             "Parameters": {

src/VirtualClient/VirtualClient.Main/profiles/PERF-SPECCPU-INTRATE.json

@@ -41,14 +41,6 @@
         }
     ],
     "Dependencies": [
-        {
-            "Type": "ExecuteCommand",
-            "Parameters": {
-                "Scenario": "MaskAptDailyTimers",
-                "SupportedPlatforms": "linux-x64,linux-arm64",
-                "Command": "bash -c 'systemctl mask apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; systemctl stop apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; exit 0'"
-            }
-        },
         {
             "Type": "ChocolateyInstallation",
             "Parameters": {

src/VirtualClient/VirtualClient.Main/profiles/PERF-SPECCPU-INTSPEED.json

@@ -41,14 +41,6 @@
         }
     ],
     "Dependencies": [
-        {
-            "Type": "ExecuteCommand",
-            "Parameters": {
-                "Scenario": "MaskAptDailyTimers",
-                "SupportedPlatforms": "linux-x64,linux-arm64",
-                "Command": "bash -c 'systemctl mask apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; systemctl stop apt-daily.timer apt-daily-upgrade.timer apt-daily.service apt-daily-upgrade.service; exit 0'"
-            }
-        },
         {
             "Type": "ChocolateyInstallation",
             "Parameters": {

src/VirtualClient/VirtualClient.UnitTests/ExecuteProfileCommandTests.cs

@@ -498,6 +498,22 @@ public async Task RunProfileCommandSupportsParametersOnListInProfile_Scenario4_P
             Assert.AreEqual("conditionalA", profile.Parameters["Parameter4"].ToString());
         }
 
+        [TestCase("Ubuntu 24.04.1 LTS", true, 24)]
+        [TestCase("Ubuntu 24.04 LTS", true, 24)]
+        [TestCase("Ubuntu 22.04.3 LTS", true, 22)]
+        [TestCase("Ubuntu 25.10", true, 25)]
+        [TestCase("ubuntu 24.04.1 lts", true, 24)]
+        [TestCase("Debian GNU/Linux 12 (bookworm)", false, 0)]
+        [TestCase("Ubuntu Noble Numbat (development branch)", false, 0)]
+        [TestCase("", false, 0)]
+        [TestCase(null, false, 0)]
+        public void TryGetUbuntuMajorVersionParsesExpectedValues(string prettyName, bool expectedSuccess, int expectedMajor)
+        {
+            bool actualSuccess = ExecuteProfileCommand.TryGetUbuntuMajorVersion(prettyName, out int actualMajor);
+            Assert.AreEqual(expectedSuccess, actualSuccess);
+            Assert.AreEqual(expectedMajor, actualMajor);
+        }
+
         private class TestRunProfileCommand : ExecuteProfileCommand
         {
             public new PlatformExtensions Extensions