diff --git a/CHANGES.txt b/CHANGES.txt
index 65875b8a15..c195d65179 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -28,6 +28,7 @@
  * Fixed multiple single-node SAI query bugs relating to static columns (CASSANDRA-20338)
  * Upgrade com.datastax.cassandra:cassandra-driver-core:3.11.5 to org.apache.cassandra:cassandra-driver-core:3.12.1 (CASSANDRA-17231)
 Merged from 4.1:
+ * Do not crash on first boot with data_disk_usage_max_disk_size set when data directory is not created yet (CASSANDRA-20787)
  * Rework / simplification of nodetool get/setguardrailsconfig commands (CASSANDRA-20778)
  * IntrusiveStack.accumulate is not accumulating correctly (CASSANDRA-20670)
  * Add nodetool get/setguardrailsconfig commands (CASSANDRA-19552)
diff --git a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
index b8991c1572..68be14cd8f 100644
--- a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
+++ b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
@@ -467,6 +467,8 @@ public class DatabaseDescriptor
 
         applySslContext();
 
+        createAllDirectories();
+
         applyGuardrails();
 
         applyStartupChecks();
diff --git a/test/distributed/org/apache/cassandra/distributed/impl/Instance.java b/test/distributed/org/apache/cassandra/distributed/impl/Instance.java
index e0eda7afce..89d7a9c348 100644
--- a/test/distributed/org/apache/cassandra/distributed/impl/Instance.java
+++ b/test/distributed/org/apache/cassandra/distributed/impl/Instance.java
@@ -608,7 +608,6 @@ public class Instance extends IsolatedExecutor implements IInvokableInstance
                         CONSISTENT_SIMULTANEOUS_MOVES_ALLOW.setBoolean(true);
                 }
 
-                mkdirs();
 
                 assert config.networkTopology().contains(config.broadcastAddress()) : String.format("Network topology %s doesn't contain the address %s",
                                                                                                     config.networkTopology(), config.broadcastAddress());
@@ -621,7 +620,6 @@ public class Instance extends IsolatedExecutor implements IInvokableInstance
                 LoggingSupportFactory.getLoggingSupport().onStartup();
 
                 FileUtils.setFSErrorHandler(new DefaultFSErrorHandler());
-                DatabaseDescriptor.createAllDirectories();
                 CassandraDaemon.getInstanceForTesting().migrateSystemDataIfNeeded();
                 CassandraDaemon.logSystemInfo(inInstancelogger);
                 CommitLog.instance.start();
@@ -824,15 +822,6 @@ public class Instance extends IsolatedExecutor implements IInvokableInstance
         ).run();
     }
 
-    private void mkdirs()
-    {
-        new File(config.getString("saved_caches_directory")).tryCreateDirectories();
-        new File(config.getString("hints_directory")).tryCreateDirectories();
-        new File(config.getString("commitlog_directory")).tryCreateDirectories();
-        for (String dir : (String[]) config.get("data_file_directories"))
-            new File(dir).tryCreateDirectories();
-    }
-
     private Config loadConfig(IInstanceConfig overrides)
     {
         Map<String, Object> params = overrides.getParams();
diff --git a/test/distributed/org/apache/cassandra/distributed/test/guardrails/GuardrailDiskUsageTest.java b/test/distributed/org/apache/cassandra/distributed/test/guardrails/GuardrailDiskUsageTest.java
index b2bb8ea098..dd205bf87a 100644
--- a/test/distributed/org/apache/cassandra/distributed/test/guardrails/GuardrailDiskUsageTest.java
+++ b/test/distributed/org/apache/cassandra/distributed/test/guardrails/GuardrailDiskUsageTest.java
@@ -72,6 +72,7 @@ public class GuardrailDiskUsageTest extends GuardrailTester
         cluster = init(Cluster.build(2)
                               .withInstanceInitializer(DiskStateInjection::install)
                               .withConfig(c -> c.with(Feature.GOSSIP, Feature.NATIVE_PROTOCOL)
+                                                .set("data_disk_usage_max_disk_size", "10GiB")
                                                 .set("data_disk_usage_percentage_warn_threshold", 98)
                                                 .set("data_disk_usage_percentage_fail_threshold", 99)
                                                 .set("authenticator", "PasswordAuthenticator"))