feat: Support graceful shutdown

CHANGELOG.md

@@ -9,6 +9,7 @@ All notable changes to this project will be documented in this file.
 - Default stackableVersion to operator version ([#381]).
 - Configuration overrides for the JVM security properties, such as DNS caching ([#384]).
 - Support PodDisruptionBudgets ([#394]).
+- Support graceful shutdown ([#407]).
 - Added support for 3.2.4, 3.3.6 ([#409]).
 
 ### Changed
@@ -33,6 +34,7 @@ All notable changes to this project will be documented in this file.
 [#402]: https://github.com/stackabletech/hdfs-operator/pull/402
 [#404]: https://github.com/stackabletech/hdfs-operator/pull/404
 [#405]: https://github.com/stackabletech/hdfs-operator/pull/405
+[#407]: https://github.com/stackabletech/hdfs-operator/pull/407
 [#409]: https://github.com/stackabletech/hdfs-operator/pull/409
 
 ## [23.7.0] - 2023-07-14

deploy/helm/hdfs-operator/crds/crds.yaml

@@ -576,6 +576,10 @@ spec:
                                   type: array
                               type: object
                           type: object
+                        gracefulShutdownTimeout:
+                          description: Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+                          nullable: true
+                          type: string
                         logging:
                           default:
                             enableVectorAgent: null
@@ -4069,6 +4073,10 @@ spec:
                                         type: array
                                     type: object
                                 type: object
+                              gracefulShutdownTimeout:
+                                description: Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+                                nullable: true
+                                type: string
                               logging:
                                 default:
                                   enableVectorAgent: null
@@ -7621,6 +7629,10 @@ spec:
                                   type: array
                               type: object
                           type: object
+                        gracefulShutdownTimeout:
+                          description: Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+                          nullable: true
+                          type: string
                         logging:
                           default:
                             enableVectorAgent: null
@@ -11105,6 +11117,10 @@ spec:
                                         type: array
                                     type: object
                                 type: object
+                              gracefulShutdownTimeout:
+                                description: Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+                                nullable: true
+                                type: string
                               logging:
                                 default:
                                   enableVectorAgent: null
@@ -14606,6 +14622,10 @@ spec:
                                   type: array
                               type: object
                           type: object
+                        gracefulShutdownTimeout:
+                          description: Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+                          nullable: true
+                          type: string
                         logging:
                           default:
                             enableVectorAgent: null
@@ -18090,6 +18110,10 @@ spec:
                                         type: array
                                     type: object
                                 type: object
+                              gracefulShutdownTimeout:
+                                description: Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+                                nullable: true
+                                type: string
                               logging:
                                 default:
                                   enableVectorAgent: null

docs/modules/hdfs/pages/usage-guide/operations/graceful-shutdown.adoc

@@ -1,6 +1,37 @@
 = Graceful shutdown
 
-Graceful shutdown of HDFS nodes is either not supported by the product itself
-or we have not implemented it yet.
+You can configure the graceful shutdown as described in xref:concepts:operations/graceful_shutdown.adoc[].
 
-Outstanding implementation work for the graceful shutdowns of all products where this functionality is relevant is tracked in https://github.com/stackabletech/issues/issues/357
+== JournalNodes
+
+As a default, JournalNodes have `15 minutes` to shut down gracefully.
+
+The JournalNode process will always run as PID `1` and will receive a `SIGTERM` signal when Kubernetes wants to terminate the Pod.
+It will log the received signal as shown in the log below and initiate a graceful shutdown.
+After the graceful shutdown timeout runs out, and the process still didn't exit, Kubernetes will issue a `SIGKILL` signal.
+
+https://github.com/apache/hadoop/blob/a585a73c3e02ac62350c136643a5e7f6095a3dbb/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/qjournal/server/JournalNode.java#L272[This] is the relevant code that gets executed in the JournalNodes as of HDFS version `3.3.4`.
+
+
+[source,text]
+----
+2023-10-10 13:37:41,525 ERROR server.JournalNode (LogAdapter.java:error(75)) - RECEIVED SIGNAL 15: SIGTERM
+2023-10-10 13:37:41,526 INFO  server.JournalNode (LogAdapter.java:info(51)) - SHUTDOWN_MSG:
+/************************************************************
+SHUTDOWN_MSG: Shutting down JournalNode at hdfs-journalnode-default-0/10.244.0.38
+************************************************************/
+----
+
+== NameNodes
+
+As a default, NameNodes have `15 minutes` to shut down gracefully.
+They use the same mechanism described above.
+
+https://github.com/apache/hadoop/blob/a585a73c3e02ac62350c136643a5e7f6095a3dbb/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNode.java#L1080[This] is the relevant code that gets executed in the NameNodes as of HDFS version `3.3.4`.
+
+== DataNodes
+
+As a default, DataNodes have `30 minutes` to shut down gracefully.
+They use the same mechanism described above.
+
+https://github.com/apache/hadoop/blob/a585a73c3e02ac62350c136643a5e7f6095a3dbb/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java#L2004[This] is the relevant code that gets executed in the DataNodes as of HDFS version `3.3.4`.

rust/crd/src/constants.rs

@@ -1,3 +1,5 @@
+use stackable_operator::time::Duration;
+
 pub const DEFAULT_DFS_REPLICATION_FACTOR: u8 = 3;
 
 pub const CONTROLLER_NAME: &str = "hdfsclusters.hdfs.stackable.tech";
@@ -41,6 +43,13 @@ pub const DEFAULT_JOURNAL_NODE_HTTP_PORT: u16 = 8480;
 pub const DEFAULT_JOURNAL_NODE_HTTPS_PORT: u16 = 8481;
 pub const DEFAULT_JOURNAL_NODE_RPC_PORT: u16 = 8485;
 
+pub const DEFAULT_JOURNAL_NODE_GRACEFUL_SHUTDOWN_TIMEOUT: Duration =
+    Duration::from_minutes_unchecked(15);
+pub const DEFAULT_NAME_NODE_GRACEFUL_SHUTDOWN_TIMEOUT: Duration =
+    Duration::from_minutes_unchecked(15);
+pub const DEFAULT_DATA_NODE_GRACEFUL_SHUTDOWN_TIMEOUT: Duration =
+    Duration::from_minutes_unchecked(30);
+
 // hdfs-site.xml
 pub const DFS_NAMENODE_NAME_DIR: &str = "dfs.namenode.name.dir";
 pub const DFS_NAMENODE_SHARED_EDITS_DIR: &str = "dfs.namenode.shared.edits.dir";

rust/crd/src/lib.rs

@@ -30,6 +30,7 @@ use stackable_operator::{
     role_utils::{GenericRoleConfig, Role, RoleGroup, RoleGroupRef},
     schemars::{self, JsonSchema},
     status::condition::{ClusterCondition, HasStatusCondition},
+    time::Duration,
 };
 use strum::{Display, EnumIter, EnumString};
 
@@ -160,6 +161,7 @@ pub trait MergedConfig {
         None
     }
     fn affinity(&self) -> &StackableAffinity;
+    fn graceful_shutdown_timeout(&self) -> Option<&Duration>;
     /// Main container shared by all roles
     fn hdfs_logging(&self) -> ContainerLogConfig;
     /// Vector container shared by all roles
@@ -845,6 +847,9 @@ pub struct NameNodeConfig {
     pub logging: Logging<NameNodeContainer>,
     #[fragment_attrs(serde(default))]
     pub affinity: StackableAffinity,
+    /// Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+    #[fragment_attrs(serde(default))]
+    pub graceful_shutdown_timeout: Option<Duration>,
 }
 
 impl MergedConfig for NameNodeConfig {
@@ -856,6 +861,10 @@ impl MergedConfig for NameNodeConfig {
         &self.affinity
     }
 
+    fn graceful_shutdown_timeout(&self) -> Option<&Duration> {
+        self.graceful_shutdown_timeout.as_ref()
+    }
+
     fn hdfs_logging(&self) -> ContainerLogConfig {
         self.logging
             .containers
@@ -920,6 +929,7 @@ impl NameNodeConfigFragment {
             },
             logging: product_logging::spec::default_logging(),
             affinity: get_affinity(cluster_name, role),
+            graceful_shutdown_timeout: Some(DEFAULT_NAME_NODE_GRACEFUL_SHUTDOWN_TIMEOUT),
         }
     }
 }
@@ -1005,6 +1015,9 @@ pub struct DataNodeConfig {
     pub logging: Logging<DataNodeContainer>,
     #[fragment_attrs(serde(default))]
     pub affinity: StackableAffinity,
+    /// Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+    #[fragment_attrs(serde(default))]
+    pub graceful_shutdown_timeout: Option<Duration>,
 }
 
 impl MergedConfig for DataNodeConfig {
@@ -1018,6 +1031,10 @@ impl MergedConfig for DataNodeConfig {
         &self.affinity
     }
 
+    fn graceful_shutdown_timeout(&self) -> Option<&Duration> {
+        self.graceful_shutdown_timeout.as_ref()
+    }
+
     fn hdfs_logging(&self) -> ContainerLogConfig {
         self.logging
             .containers
@@ -1073,6 +1090,7 @@ impl DataNodeConfigFragment {
             },
             logging: product_logging::spec::default_logging(),
             affinity: get_affinity(cluster_name, role),
+            graceful_shutdown_timeout: Some(DEFAULT_DATA_NODE_GRACEFUL_SHUTDOWN_TIMEOUT),
         }
     }
 }
@@ -1156,6 +1174,9 @@ pub struct JournalNodeConfig {
     pub logging: Logging<JournalNodeContainer>,
     #[fragment_attrs(serde(default))]
     pub affinity: StackableAffinity,
+    /// Time period Pods have to gracefully shut down, e.g. `30m`, `1h` or `2d`. Consult the operator documentation for details.
+    #[fragment_attrs(serde(default))]
+    pub graceful_shutdown_timeout: Option<Duration>,
 }
 
 impl MergedConfig for JournalNodeConfig {
@@ -1167,6 +1188,10 @@ impl MergedConfig for JournalNodeConfig {
         &self.affinity
     }
 
+    fn graceful_shutdown_timeout(&self) -> Option<&Duration> {
+        self.graceful_shutdown_timeout.as_ref()
+    }
+
     fn hdfs_logging(&self) -> ContainerLogConfig {
         self.logging
             .containers
@@ -1210,6 +1235,7 @@ impl JournalNodeConfigFragment {
             },
             logging: product_logging::spec::default_logging(),
             affinity: get_affinity(cluster_name, role),
+            graceful_shutdown_timeout: Some(DEFAULT_JOURNAL_NODE_GRACEFUL_SHUTDOWN_TIMEOUT),
         }
     }
 }

rust/operator/src/container.rs

@@ -28,7 +28,13 @@ use stackable_hdfs_crd::{
     storage::DataNodeStorageConfig,
     DataNodeContainer, HdfsCluster, HdfsPodRef, HdfsRole, MergedConfig, NameNodeContainer,
 };
-use stackable_operator::builder::SecretFormat;
+use stackable_operator::{
+    builder::SecretFormat,
+    product_logging::framework::{
+        create_vector_shutdown_file_command, remove_vector_shutdown_file_command,
+    },
+    utils::COMMON_BASH_TRAP_FUNCTIONS,
+};
 use stackable_operator::{
     builder::{
         resources::ResourceRequirementsBuilder, ContainerBuilder, PodBuilder,
@@ -45,9 +51,12 @@ use stackable_operator::{
     },
     kube::ResourceExt,
     memory::{BinaryMultiple, MemoryQuantity},
-    product_logging,
-    product_logging::spec::{
-        ConfigMapLogConfig, ContainerLogConfig, ContainerLogConfigChoice, CustomContainerLogConfig,
+    product_logging::{
+        self,
+        spec::{
+            ConfigMapLogConfig, ContainerLogConfig, ContainerLogConfigChoice,
+            CustomContainerLogConfig,
+        },
     },
 };
 use std::{collections::BTreeMap, str::FromStr};
@@ -437,9 +446,21 @@ impl ContainerConfig {
                     HDFS_LOG4J_CONFIG_FILE,
                     merged_config.hdfs_logging(),
                 ));
+
                 args.push_str(&format!(
-                    "{hadoop_home}/bin/hdfs {role}\n",
+                    "\
+{COMMON_BASH_TRAP_FUNCTIONS}
+{remove_vector_shutdown_file_command}
+prepare_signal_handlers
+{hadoop_home}/bin/hdfs {role} &
+wait_for_termination $!
+{create_vector_shutdown_file_command}
+",
                     hadoop_home = Self::HADOOP_HOME,
+                    remove_vector_shutdown_file_command =
+                        remove_vector_shutdown_file_command(STACKABLE_LOG_DIR),
+                    create_vector_shutdown_file_command =
+                        create_vector_shutdown_file_command(STACKABLE_LOG_DIR),
                 ));
             }
             ContainerConfig::Zkfc { .. } => {

rust/operator/src/hdfs_controller.rs

@@ -54,7 +54,10 @@ use crate::{
     discovery::build_discovery_configmap,
     event::{build_invalid_replica_message, publish_event},
     kerberos,
-    operations::pdb::add_pdbs,
+    operations::{
+        graceful_shutdown::{self, add_graceful_shutdown_config},
+        pdb::add_pdbs,
+    },
     product_logging::{extend_role_group_config_map, resolve_vector_aggregator_address},
     OPERATOR_NAME,
 };
@@ -204,6 +207,9 @@ pub enum Error {
         source: PropertiesWriterError,
         rolegroup: String,
     },
+
+    #[snafu(display("failed to configure graceful shutdown"))]
+    GracefulShutdown { source: graceful_shutdown::Error },
 }
 
 impl ReconcilerError for Error {
@@ -694,6 +700,8 @@ fn rolegroup_statefulset(
     )
     .context(FailedToCreateContainerAndVolumeConfigurationSnafu)?;
 
+    add_graceful_shutdown_config(merged_config, &mut pb).context(GracefulShutdownSnafu)?;
+
     let mut pod_template = pb.build_template();
     if let Some(pod_overrides) = hdfs.pod_overrides_for_role(role) {
         pod_template.merge_from(pod_overrides.clone());

rust/operator/src/operations/graceful_shutdown.rs

@@ -0,0 +1,26 @@
+use snafu::{ResultExt, Snafu};
+use stackable_hdfs_crd::MergedConfig;
+use stackable_operator::builder::PodBuilder;
+
+#[derive(Debug, Snafu)]
+pub enum Error {
+    #[snafu(display("Failed to set terminationGracePeriod"))]
+    SetTerminationGracePeriod {
+        source: stackable_operator::builder::pod::Error,
+    },
+}
+
+pub fn add_graceful_shutdown_config(
+    merged_config: &(dyn MergedConfig + Send + 'static),
+    pod_builder: &mut PodBuilder,
+) -> Result<(), Error> {
+    // This must be always set by the merge mechanism, as we provide a default value,
+    // users can not disable graceful shutdown.
+    if let Some(graceful_shutdown_timeout) = merged_config.graceful_shutdown_timeout() {
+        pod_builder
+            .termination_grace_period(graceful_shutdown_timeout)
+            .context(SetTerminationGracePeriodSnafu)?;
+    }
+
+    Ok(())
+}

rust/operator/src/operations/mod.rs

@@ -1 +1,2 @@
+pub mod graceful_shutdown;
 pub mod pdb;

tests/templates/kuttl/smoke/30-assert.yaml.j2

@@ -23,6 +23,7 @@ spec:
         - name: vector
 {% endif %}
         - name: zkfc
+      terminationGracePeriodSeconds: 900
 status:
   readyReplicas: 2
   replicas: 2
@@ -46,6 +47,7 @@ spec:
 {% if lookup('env', 'VECTOR_AGGREGATOR') %}
         - name: vector
 {% endif %}
+      terminationGracePeriodSeconds: 900
 status:
   readyReplicas: 1
   replicas: 1
@@ -69,6 +71,7 @@ spec:
 {% if lookup('env', 'VECTOR_AGGREGATOR') %}
         - name: vector
 {% endif %}
+      terminationGracePeriodSeconds: 1800
 status:
   readyReplicas: {{ test_scenario['values']['number-of-datanodes'] }}
   replicas: {{ test_scenario['values']['number-of-datanodes'] }}