diff --git a/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServer.java b/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServer.java
index ce374017..ef78541c 100644
--- a/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServer.java
+++ b/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServer.java
@@ -159,24 +159,6 @@ public LaunchServer(LaunchServerDirectories directories, LaunchServerEnv env, La
             });
             LogHelper.debug("Init components successful");
         }
-        // Sync updates dir
-        CommonHelper.newThread("Profiles and updates sync", true, () -> {
-            try {
-                if (!IOHelper.isDir(updatesDir))
-                    Files.createDirectory(updatesDir);
-                syncUpdatesDir(null);
-                modulesManager.invokeEvent(new LaunchServerUpdatesSyncEvent(this));
-
-                // Sync profiles dir
-                if (!IOHelper.isDir(profilesDir))
-                    Files.createDirectory(profilesDir);
-                syncProfilesDir();
-                modulesManager.invokeEvent(new LaunchServerProfilesSyncEvent(this));
-            } catch (IOException e) {
-                LogHelper.error(e);
-                LogHelper.error("Updates/Profiles not synced");
-            }
-        });
         launcherModuleLoader.init();
         nettyServerSocketHandler = new NettyServerSocketHandler(this);
         // post init modules
@@ -318,6 +300,24 @@ public void run() {
                 }
             }));
             CommonHelper.newThread("Command Thread", true, commandHandler).start();
+            // Sync updates dir
+            CommonHelper.newThread("Profiles and updates sync", true, () -> {
+                try {
+                    if (!IOHelper.isDir(updatesDir))
+                        Files.createDirectory(updatesDir);
+                    syncUpdatesDir(null);
+                    modulesManager.invokeEvent(new LaunchServerUpdatesSyncEvent(this));
+
+                    // Sync profiles dir
+                    if (!IOHelper.isDir(profilesDir))
+                        Files.createDirectory(profilesDir);
+                    syncProfilesDir();
+                    modulesManager.invokeEvent(new LaunchServerProfilesSyncEvent(this));
+                } catch (IOException e) {
+                    LogHelper.error(e);
+                    LogHelper.error("Updates/Profiles not synced");
+                }
+            });
         }
         if (config.netty != null)
             rebindNettyServerSocket();
diff --git a/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServerStarter.java b/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServerStarter.java
index 16d4ef25..9b952854 100644
--- a/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServerStarter.java
+++ b/LaunchServer/src/main/java/pro/gravit/launchserver/LaunchServerStarter.java
@@ -44,6 +44,7 @@
 public class LaunchServerStarter {
     public static final boolean allowUnsigned = Boolean.getBoolean("launchserver.allowUnsigned");
     public static final boolean inDocker = Boolean.getBoolean("launchserver.dockered");
+    public static final boolean prepareMode = Boolean.getBoolean("launchserver.prepareMode");
 
     public static void main(String[] args) throws Exception {
         JVMHelper.checkStackTrace(LaunchServerStarter.class);
@@ -209,7 +210,11 @@ public void writeRuntimeConfig(LaunchServerRuntimeConfig config) throws IOExcept
                 .setLaunchServerConfigManager(launchServerConfigManager)
                 .setCertificateManager(certificateManager)
                 .build();
-        server.run();
+        if(!prepareMode) {
+            server.run();
+        } else {
+            server.close();
+        }
     }
 
     public static void initGson(LaunchServerModulesManager modulesManager) {
diff --git a/LaunchServer/src/main/java/pro/gravit/launchserver/command/service/SecurityCheckCommand.java b/LaunchServer/src/main/java/pro/gravit/launchserver/command/service/SecurityCheckCommand.java
index b1a2c032..75ce8c25 100644
--- a/LaunchServer/src/main/java/pro/gravit/launchserver/command/service/SecurityCheckCommand.java
+++ b/LaunchServer/src/main/java/pro/gravit/launchserver/command/service/SecurityCheckCommand.java
@@ -12,8 +12,17 @@
 import pro.gravit.launchserver.components.ProGuardComponent;
 import pro.gravit.launchserver.config.LaunchServerConfig;
 import pro.gravit.utils.helper.FormatHelper;
+import pro.gravit.utils.helper.IOHelper;
+import pro.gravit.utils.helper.JVMHelper;
 import pro.gravit.utils.helper.LogHelper;
 
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.LinkOption;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.attribute.PosixFilePermission;
+import java.util.Set;
 import java.util.StringTokenizer;
 
 public class SecurityCheckCommand extends Command {
@@ -188,6 +197,54 @@ public void invoke(String... args) {
             if (!bad)
                 printCheckResult(LogHelper.Level.INFO, profileModuleName, "", true);
         }
+
+        //Linux permissions check
+        if(JVMHelper.OS_TYPE == JVMHelper.OS.LINUX) {
+            try {
+                int uid = 0, gid = 0;
+                String[] status = new String(IOHelper.read(Paths.get("/proc/self/status"))).split("\n");
+                for(String line : status) {
+                    String[] parts = line.split(":");
+                    if(parts.length == 0) continue;
+                    if(parts[0].trim().equalsIgnoreCase("Uid")) {
+                        String[] words = parts[1].trim().split(" ");
+                        uid = Integer.parseInt(words[0]);
+                        if(Integer.parseInt(words[0]) == 0 || Integer.parseInt(words[0]) == 0) {
+                            LogHelper.error("The process is started as root! It is not recommended");
+                        }
+                    }
+                    if(parts[0].trim().equalsIgnoreCase("Gid")) {
+                        String[] words = parts[1].trim().split(" ");
+                        gid = Integer.parseInt(words[0]);
+                        if(Integer.parseInt(words[0]) == 0 || Integer.parseInt(words[0]) == 0) {
+                            LogHelper.error("The process is started as root group! It is not recommended");
+                        }
+                    }
+                }
+                if(checkOtherWriteAccess(IOHelper.getCodeSource(LaunchServer.class))) {
+                    LogHelper.warning("Write access to LaunchServer.jar. Please use 'chmod 755 LaunchServer.jar'");
+                }
+                if(Files.exists(server.dir.resolve("private.key")) && checkOtherReadOrWriteAccess(server.dir.resolve("private.key"))) {
+                    LogHelper.warning("Write or read access to private.key. Please use 'chmod 600 private.key'");
+                }
+                if(Files.exists(server.dir.resolve("LaunchServerConfig.json")) && checkOtherReadOrWriteAccess(server.dir.resolve("LaunchServerConfig.json"))) {
+                    LogHelper.warning("Write or read access to LaunchServerConfig.json. Please use 'chmod 600 LaunchServerConfig.json'");
+                }
+                if(Files.exists(server.dir.resolve("LaunchServerRuntimeConfig.json")) && checkOtherReadOrWriteAccess(server.dir.resolve("LaunchServerRuntimeConfig.json"))) {
+                    LogHelper.warning("Write or read access to LaunchServerRuntimeConfig.json. Please use 'chmod 600 LaunchServerRuntimeConfig.json'");
+                }
+            } catch (IOException e) {
+                LogHelper.error(e);
+            }
+        }
         LogHelper.info("Check completed");
     }
+    public boolean checkOtherWriteAccess(Path file) throws IOException {
+        Set<PosixFilePermission> permissionSet = Files.getPosixFilePermissions(file);
+        return permissionSet.contains(PosixFilePermission.OTHERS_WRITE);
+    }
+    public boolean checkOtherReadOrWriteAccess(Path file) throws IOException {
+        Set<PosixFilePermission> permissionSet = Files.getPosixFilePermissions(file);
+        return permissionSet.contains(PosixFilePermission.OTHERS_WRITE) || permissionSet.contains(PosixFilePermission.OTHERS_READ);
+    }
 }