Looking at log and configuration information can be useful to troubleshoot a cluster or job. Unfortunately, there are many log and configuration files, and gathering each one for investigation can be time consuming. To address this problem, Cloud Dataproc clusters support a special diagnose command through the Cloud SDK. This command gathers and archives important system, Spark/Hadoop, and Cloud Dataproc logs, and then uploads the archive to the Cloud Storage bucket attached to your cluster.
Using the diagnose command
You can use the Cloud SDK diagnose command on your Cloud Dataproc clusters (see Dataproc and Cloud SDK).
Once the Cloud SDK is installed and configured, you can run the
gcloud dataproc clusters diagnose
command on your cluster as shown below. Replace cluster-name with the
name of your cluster and region with your cluster's region, for
example, --region=us-central1.
gcloud dataproc clusters diagnose cluster-name \ --region=region \ ... other args ...
The command outputs the name and location of the archive that contains your data.
...
Saving archive to cloud
Copying file:///tmp/tmp.FgWEq3f2DJ/diagnostic.tar ...
Uploading ...23db9-762e-4593-8a5a-f4abd75527e6/diagnostic.tar ...
Diagnostic results saved in:
gs://bucket-name/.../cluster-uuid/.../job-id/diagnostic.tar
...
In this example, bucket-name is the Cloud Storage bucket attached to your cluster, cluster-uuid is the unique ID (UUID) of your cluster, and job-id is the UUID belonging to the system task that ran the diagnose command.
When you create a Cloud Dataproc cluster, Cloud Dataproc automatically creates a Cloud Storage bucket and attaches it to your cluster. The diagnose command outputs the archive file to this bucket. To determine the name of the bucket created by Cloud Dataproc, use the Cloud SDK clusters describe command. The bucket associated with your cluster is listed next to configurationBucket.
gcloud dataproc clusters describe cluster-name \ --region=region \ ... clusterName: cluster-name clusterUuid: daa40b3f-5ff5-4e89-9bf1-bcbfec6e0eac configuration: configurationBucket: dataproc-edc9d85f-...-us ...
Sharing the data gathered by diagnose
You can share the archive generated by the diagnose command in two ways:
- Download the file from Cloud Storage, then share the downloaded archive.
- Change the permissions on the archive to allow other Google Cloud Platform users or projects to access the file.
For example, the following command adds read permissions to the diagnose archive in a test-project:
gsutil -m acl ch -g test-project:R path-to-archive
Items included in diagnose command output
The diagnose command includes the following configuration files, logs, and outputs from your cluster in an archive file. The archive file is placed in the Cloud Storage bucket associated with your Cloud Dataproc cluster, as discussed above.
Daemon and state information
| Command executed | Location in archive |
|---|---|
yarn node -list -all |
/system/yarn-nodes.log |
hdfs dfsadmin -report -live -decommissioning |
/system/hdfs-nodes.log |
service --status-all |
/system/service.log |
df -h |
/system/df.log |
ps aux |
/system/ps.log |
free -m |
/system/free.log |
netstat -anp |
/system/netstat.log |
sysctl -a |
/system/sysctl.log |
uptime |
/system/uptime.log |
cat /proc/sys/fs/file-nr |
/system/fs-file-nr.log |
ping -c 1 |
/system/cluster-ping.log |
Logfiles
| Item(s) included | Location in archive |
|---|---|
All logs in /var/log with the following prefixes in their filename:gcsgooglegcdphadoophdfshivesparksyslogyarn |
Files are placed in the archive logs folder, and keep their original filenames. |
| Cloud Dataproc node startup logs for each node (master and worker) in your cluster. | Files are placed in the archive node_startup folder, which contains separate sub-folders for each machine in the cluster. |
Configuration files
| Item(s) included | Location in archive |
|---|---|
All files in /etc/hadoop/conf/ |
Files are placed in the archive hadoop_conf folder, and keep their original filenames. |