Troubleshooting MySQL for PCF

Warning: MySQL for PCF v2.5 is no longer supported because it has reached the End of General Support (EOGS) phase as defined by the Support Lifecycle Policy. To stay up to date with the latest software and security updates, upgrade to a supported version.

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This topic provides operators with basic instructions for troubleshooting on-demand MySQL for PCF. For information about temporary MySQL for PCF service interruptions, see Service Interruptions.

Troubleshooting Errors

This section provides information about how to troubleshooting specific errors or error messages.

Deprecated Service Bindings Found (Upgrade Error)

This problem happens when upgrading to MySQL for PCF v2.5 if there are service bindings that are still using IP addresses.

Symptom

You see in the Ops Manager installation pane that the upgrade process fails at the following step:

The error output in the logs contains a table of bindings or service keys which must be updated.

stdout    +---------------------------+--------------------------------------+------------------------+--------------------------+--------------------+-------------------+-----------------------------+
          |          service          |             service guid             |          org           |          space           | app or service key |       type        |           reason            |
          +---------------------------+--------------------------------------+------------------------+--------------------------+--------------------+-------------------+-----------------------------+
          | upgrade-outdated-instance | 34f26746-fb46-4f14-87bc-e1ddce26f340 | mysql-org-upgrade-test | mysql-space-upgrade-test | cs-accept          | appbinding        | no dns: hostname="10.0.8.5" |
          +---------------------------+--------------------------------------+------------------------+--------------------------+--------------------+-------------------+-----------------------------+
          | tlsdb                     | a999db0b-176e-4ac8-8342-d72b338d1f0c | mysql-org-upgrade-test | mysql-space-upgrade-test | cs-accept-tls      | appbinding        | no dns: hostname="10.0.8.6" |
          +---------------------------+--------------------------------------+------------------------+--------------------------+--------------------+-------------------+-----------------------------+
          | tlsdb                     | a999db0b-176e-4ac8-8342-d72b338d1f0c | mysql-org-upgrade-test | mysql-space-upgrade-test | test-cli           | servicekeybinding | no dns: hostname="10.0.8.6" |
          +---------------------------+--------------------------------------+------------------------+--------------------------+--------------------+-------------------+-----------------------------+

errand 'validate-before-upgrade-instances' completed with error (exit code 1)
exit code 1
stderr     2018/12/18 02:51:51 deprecated service instances found, try upgrade it manually before upgrading tile

Explanation

In MySQL for PCF v2.5, if you run upgrade-all-service-instances while there are service bindings that use IP addresses, app downtime can occur. This is because bindings are still directing apps to connect with IP addresses, but the TLS certificate is signed with a DNS hostname. This prevents apps that validate the server hostname in the TLS certificate from establishing a TLS connection to the database.

In MySQL for PCF v2.5, the validate-before-upgrade-instances errand checks that there are no service bindings or service keys using IP addresses, and, if there are, outputs the above error and prevents the upgrade-all-service-instances errand from running.

For general information about errands, including the upgrade-all-service-instances errand, see MySQL for PCF Errands.

Solution

To solve this issue, do the following:

1. Do the procedures in Remove IP-Based Bindings.
   After you restart all of your apps, your apps can connect to the database and resume service. However, your Ops Manager installation is still in a failed state.
2. To finish the installation, do the following:
   1. In the Ops Manager Installation Dashboard, click Review Pending Changes.
   2. In the Review Pending Changes pane, ensure that the Validate no IP-based bindings in use before upgrade-all-service-instances and Upgrade all On-demand MySQL Service Instances errands are selected.
   3. After reviewing the pending changes, click Apply Changes to complete the installation.

Failed Install

Reasons for a failed MySQL for PCF installation include:

1. Certificate issues: The on-demand broker (ODB) requires valid certificates. Ensure that your certificates are valid and generate new ones if necessary. To generate new certificates, contact Pivotal Support.
2. Deploy fails: Deploys can fail for a variety of reasons. View the logs using Ops Manager to determine why the deploy is failing.
3. Networking problems:
• Cloud Foundry cannot reach the MySQL for PCF service broker
• Cloud Foundry cannot reach the service instances
• The service network cannot access the BOSH director
4. The Register broker errand fails.
5. The smoke test errand fails.
6. Resource sizing issues: These occur when the resource sizes selected for a given plan are less than the MySQL for PCF service requires to function. Check your resource configuration in Ops Manager and ensure that the configuration matches that recommended by the service.
7. Other service-specific issues.

Cannot Create or Delete Service Instances

If developers report errors such as:

Instance provisioning failed: There was a problem completing your request. Please contact your operations team providing the following information: service: redis-acceptance, service-instance-guid: ae9e232c-0bd5-4684-af27-1b08b0c70089, broker-request-id: 63da3a35-24aa-4183-aec6-db8294506bac, task-id: 442, operation: create

Follow these steps:

1. If the BOSH error shows a problem with the deployment manifest, open the manifest in a text editor to inspect it.

2. To continue troubleshooting, Log in to BOSH and target the MySQL for PCF service instance using the instructions on parsing a Cloud Foundry error message.

3. Retrieve the BOSH task ID from the error message and run the following command:

   bosh task TASK-ID

4. If you need more information, access the broker logs and use the broker-request-id from the error message above to search the logs for more information. Check for:

• Authentication errors
• Network errors
• Quota errors

Broker Request Timeouts

If developers report errors such as:

Server error, status code: 504, error code: 10001, message: The request to the service broker timed out: https://BROKER-URL/v2/service_instances/e34046d3-2379-40d0-a318-d54fc7a5b13f/service_bindings/aa635a3b-ef6d-41c3-a23f-55752f3f651b

Follow these steps:

1. Confirm that Cloud Foundry (CF) is connected to the service broker.
2. Check the BOSH queue size:
   1. Log into BOSH as an admin.
   2. Run bosh tasks.
3. If there are a large number of queued tasks, the system may be under too much load. BOSH is configured with two workers and one status worker, which may not be sufficient resources for the level of load. Advise app developers to try again once the system is under less load.

Cannot Bind to or Unbind from Service Instances

Instance Does Not Exist

If developers report errors such as:

Server error, status code: 502, error code: 10001, message: Service broker error: instance does not exist`

Follow these steps:

1. Confirm that the MySQL for PCF service instance exists in BOSH and obtain the GUID CF by running:

   cf service MY-INSTANCE --guid

2. Using the GUID obtained above, the following BOSH CLI command:

   bosh -d service-instance_GUID vms

If the BOSH deployment is not found, it has been deleted from BOSH. Contact Pivotal support for further assistance.

Other Errors

If developers report errors such as:

Server error, status code: 502, error code: 10001, message: Service broker error: There was a problem completing your request. Please contact your operations team providing the following information: service: example-service, service-instance-guid: 8d69de6c-88c6-4283-b8bc-1c46103714e2, broker-request-id: 15f4f87e-200a-4b1a-b76c-1c4b6597c2e1, operation: bind

To find out the exact issue with the binding process:

1. Access the service broker logs.

2. Search the logs for the broker-request-id string listed in the error message above.

3. Contact Pivotal support for further assistance if you are unable to resolve the problem.

4. Check for:

• Authentication errors
• Network errors

Cannot Connect to a Service Instance

If developers report that their app cannot use service instances that they have successfully created and bound:

Ask the user to send application logs that show the connection error. If the error is originating from the service, then follow MySQL for PCF-specific instructions. If the issue appears to be network-related, then:

1. Check that application security groups are configured correctly. Access should be configured for the service network that the tile is deployed to.

2. Ensure that the network the Pivotal Application Service tile is deployed to has network access to the service network. You can find the network definition for this service network in the BOSH Director tile.

3. In Ops Manager go into the service tile and see the service network that is configured in the networks tab.

4. In Ops Manager go into the tile and see the network it is assigned to. Make sure that these networks can access each other.

Service instances can also become temporarily inaccessible during upgrades and VM or network failures. See Service Interruptions for more information.

Upgrade All Instances Fails

If the upgrade-all-service-instances errand fails, look at the errand output in the Ops Manager log.

If an instance fails to upgrade, debug and fix it before running the errand again to prevent any failure issues from spreading to other on-demand instances.

Once the Ops Manager log no longer lists the deployment as failing, re-run the errand to upgrade the rest of the instances.

Missing Logs and Metrics

If no logs are being emitted by the on-demand broker, check that your syslog forwarding address is correct in Ops Manager.

1. Ensure you have configured syslog for the tile.

2. Ensure that you have network connectivity between the networks that the tile is using and the syslog destination. If the destination is external, you need to use the public ip VM extension feature available in your Ops Manager tile configuration settings.

3. Verify that Loggregator is emitting metrics:

   1. Install the cf log-stream plugin. For instructions, see the Log Stream CLI Plugin GitHub repository.

   2. Find the GUID for your service instance by running:

      cf service SERVICE-INSTANCE --guid

   3. Find logs from your service instance by running:

      cf log-stream | grep "SERVICE-GUID"

If no metrics appear within five minutes, verify that the broker network has access to the Loggregator system on all required ports.

Contact Pivotal support if you are unable to resolve the issue.

Unable to Determine Leader and Follower (Errand Error)

This problem happens when the configure-leader-follower errand fails because it cannot determine the VM roles.

Symptom

The configure-leader-follower errand exits with 1 and the errand logs contain the following:

$ Unable to determine leader and follower based on transaction history.

Explanation

Something has happened to the instances, such as a failure or manual intervention. As a result, there is not enough information available to determine the correct state and topology without operator intervention to resolve the issue.

Solution

Use the inspect errand to determine which instance should be the leader. Then, using the orchestration errands and backup/restore, you can put the service instance into a safe topology, and then rerun the configure-leader-follower errand. This is shown in the example below. This example shows one outcome that the inspect errand can return:

1. Use the inspect errand to retrieve relevant information about the two VMs:

     $ bosh -e my-env -d my-dep run-errand inspect
     [...]
     Instance   mysql/4ecad54b-0704-47eb-8eef-eb228cab9724
     Exit Code  0
     Stdout     -
     Stderr     2017/12/11 18:25:54 Started executing command: inspect
              2017/12/11 18:25:54 Started GET https://127.0.0.1:8443/status
              2017/12/11 18:25:54
              Has Data: false
              Read Only: true
              GTID Executed: 1d774323-de9e-11e7-be01-42010a001014:1-25
              Replication Configured: false
   
   
     Instance   mysql/e0b94ade-0114-4d49-a929-ce1616d8beda
     Exit Code  0
     Stdout     -
     Stderr     2017/12/11 18:25:54 Started executing command: inspect
              2017/12/11 18:25:54 Started GET https://127.0.0.1:8443/status
              2017/12/11 18:25:54
              Has Data: true
              Read Only: true
              GTID Executed: 1d774323-de9e-11e7-be01-42010a001014:1-25
              Replication Configured: true
   
   
     2 errand(s)
   
     Succeeded
     

   In the above scenario, the first instance is missing data but does not have replication configured. The second instance has data, and also has replication configured. The instructions below resolve this by copying data to the first instance, and resuming replication.
2. Take a backup of the second instance using the Manual Backup steps.
3. Restore the backup artifact to the first instance using the Manual Restore steps.
   
   At this point, the instances have equivalent data.
4. Run the configure-leader-follower errand to reconfigure replication:

   bosh -e ENVIRONMENT -d DEPLOYMENT run-errand configure-leader-follower --instance=mysql/GUID-OF-LEADER

   For example:

   $ bosh -e my-env -d my-dep \
       run-errand configure-leader-follower \
       --instance=mysql/4ecad54b-0704-47eb-8eef-eb228cab9724

Both Leader and Follower Instances Are Writable (Errand Error)

This problem happens when theconfigure-leader-follower

errand fails because both VMs are writable and the VMs might hold differing data.

Symptom

The configure–leader-follower errand exits with 1 and the errand logs contain the following:

$ Both mysql instances are writable. Please ensure no divergent data and set one instance to read-only mode.

Explanation

MySQL for PCF tries to ensure that there is only one writable instance of the leader-follower pair at any given time. However, in certain situations, such as network partitions, or manual intervention outside of the provided bosh errands, it is possible for both instances to be writable. The service instances remain in this state until an operator resolves the issue to ensure that the correct instance is promoted and reduce the potential for data divergence.

Solution

1. Use the inspect errand to retrieve the GTID Executed set for each VM:

   $ bosh -e my-env -d my-dep run-errand inspect
     [...]
     Instance   mysql/4ecad54b-0704-47eb-8eef-eb228cab9724
     Exit Code  0
     Stdout     -
     Stderr     2017/12/11 18:25:54 Started executing command: inspect
              2017/12/11 18:25:54 Started GET https:127.0.0.1:8443/status
              2017/12/11 18:25:54
              Has Data: true
              Read Only: false
              GTID Executed: 1d774323-de9e-11e7-be01-42010a001014:1-23
              Replication Configured: false
   
   
     Instance   mysql/e0b94ade-0114-4d49-a929-ce1616d8beda
     Exit Code  0
     Stdout     -
     Stderr     2017/12/11 18:25:54 Started executing command: inspect
              2017/12/11 18:25:54 Started GET https:127.0.0.1:8443/status
              2017/12/11 18:25:54
              Has Data: true
              Read Only: false
              GTID Executed: 1d774323-de9e-11e7-be01-42010a001014:1-25
              Replication Configured: false
   
   
     2 errand(s)
   
     Succeeded
   

   If the GTID Executed sets for both instances are the same, continue to Step 2. If they are different, continue to Step 4.
2. Look at the value of GTID Executed for both instances.
   • If the range after the GUID is equivalent, either instance can be made read-only, as described in Step 3.
   • If one instance has a range that is a subset of the other, the instance with the subset should must be made read-only, as described in Step 3.
3. Based on the information you gathered in the step above, run the make-read-only errand to make the appropriate instance read-only:

   bosh -e ENVIRONMENT -d DEPLOYMENT run-errand make-read-only --instance=mysql/MYSQL-SUBSET-INSTANCE

   For example:

   $ bosh -e my-env -d my-dep \
           run-errand make-read-only \
           --instance=mysql/e0b94ade-0114-4d49-a929-ce1616d8beda
         [...]
         succeeded

4. If the GTID Executed sets are neither equivalent nor subsets, data has diverged and you must determine what data has diverged as part of the procedure below:
   1. Use the make-read-only errand to set both instances to read-only to prevent further data divergence.

      bosh -e ENVIRONMENT -d DEPLOYMENT run-errand make-read-only --instance=mysql/MYSQL-INSTANCE

      For example:

      $ bosh -e my-env -d my-dep \
                  run-errand make-read-only \
                  --instance=mysql/e0b94ade-0114-4d49-a929-ce1616d8beda
                  [...]
                  succeeded

   2. Take a backup of both instances using the Manual Backup steps.
   3. Manually inspect the data on each instance to determine the discrepancies and put the data on the instance that is further ahead—this instance has the higher GTID Executed set, and will be the new leader.
   4. Migrate all appropriate data to the new leader instance.
   5. After putting all data on the leader, ssh onto the follower:

      bosh -e ENVIRONMENT -d DEPLOYMENT ssh mysql/GUID-OF-FOLLOWER

      For example:

      $ bosh -e my-env -d my-dep ssh mysql/e0b94ade-0114-4d49-a929-ce1616d8beda

   6. Become root with the command sudo su.
      
   7. Stop the mysql process with the command monit stop mysql.
   8. Delete the data directory of the follower with the command rm -rf /var/vcap/store/mysql.
   9. Start the mysql process with the command monit start mysql.
   10. Use the configure-leader-follower errand to copy the leader’s data to the follower and resume replication:

       bosh -e ENVIRONMENT -d DEPLOYMENT run-errand configure-leader-follower --instance=mysql/GUID-OF-LEADER

       For example:

       $ bosh -e my-env -d my-dep \
                 run-errand configure-leader-follower \
                 --instance=mysql/4ecad54b-0704-47eb-8eef-eb228cab9724

Both Leader and Follower Instances Are Read-Only

In a leader-follower topology, the leader VM is writable and the follower VM is read-only. However if both VMs are read only, apps cannot write to the database.

Symptom

Developers report that apps cannot write to the database.

Explanation

This problem happens if the leader VM fails and the BOSH Resurrector is enabled. When the leader is resurrected, it is set as read-only.

Solution

1. Use the inspect errand to confirm that both VMs are in a read-only state:

   bosh -e ENVIRONMENT -d DEPLOYMENT run-errand inspect

2. Examine the output and locate the information about the leader-follower MySQL VMs:

   Instance   mysql/4eexample54b-0704-47eb-8eef-eb2example724
   Exit Code  0
   Stdout     -
   Stderr     2017/12/11 18:25:54 Started executing command: inspect
            2017/12/11 18:25:54 Started GET https:999.0.0.1:8443/status
            2017/12/11 18:25:54
            Has Data: true
            Read Only: true
            GTID Executed: 1d779999-de9e-11e7-be01-42010a009999:1-23
            Replication Configured: true
   
   
   Instance   mysql/e0exampleade-0114-4d49-a929-cexample8beda
   Exit Code  0
   Stdout     -
   Stderr     2017/12/11 18:25:54 Started executing command: inspect
            2017/12/11 18:25:54 Started GET https:999.0.0.1:8443/status
            2017/12/11 18:25:54
            Has Data: true
            Read Only: true
            GTID Executed: 1d779999-de9e-11e7-be01-42010a009999:1-25
            Replication Configured: false
   
   
   2 errand(s)
   
   Succeeded
   

3. If Read Only is set to true for both VMs, make the leader writable using the following command:

   bosh -e ENVIRONMENT -d DEPLOYMENT run-errand configure-leader-follower --instance=mysql/GUID-OF-LEADER

   For example, if the second instance above is the leader:

   $ bosh -e my-env -d my-dep \
     run-errand configure-leader-follower \
     --instance=mysql/e0exampleade-0114-4d49-a929-cexample8beda
   

Persistent Disk is Full

If your persistent disk is full, apps become inoperable. In this state, read, write, and Cloud Foundry Command-Line Interface (cf CLI) operations do not work.

Symptom

Developers report that read, write, and cf CLI operations do not work. Developers cannot upgrade to a larger MySQL service plan to free up disk space.

Explanation

This problem happens if your persistent disk is full. When you use the BOSH CLI to target your deployment, you see that instances are at 100% persistent disk usage.

Available disk space can be increased by deleting log files. After deleting logs, you can then upgrade to a larger MySQL service plan.

Solution

To resolve this issue, you must free up disk space by deleting binary logs.

For instructions for deleting binary logs, see MySQL for PCF hangs when server VM persistent disk is full in the Pivotal Support knowledge base.

Warning: Deleting binary logs is a destructive procedure and can result in MySQL data loss. Only do this procedure with the assistance of Pivotal Support.

Unresponsive Node in a Highly Available Cluster

Symptom

A client connected to a MySQL cluster node reports the following error:

WSREP has not yet prepared this node for application use

Some clients might instead return the following:

  unknown error

Explanation

If the client is connected to a MySQL cluster node and that node loses connection to the rest of the cluster, the node stops accepting writes. If the connection to this node is made through the proxy, the proxy automatically re-routes further connections to a different node.

Solutions

A node can become unresponsive for a number of reasons. For solutions, see the following:

• Network Latency: If network latency causes a node to become unresponsive, the node drops but eventually rejoins. The node automatically rejoins only if one node has left the cluster. Consult your IaaS network settings to reduce your network latency.
• MySQL Process Failure: If the MySQL process crashes, monit and BOSH should restore the process. If the process is not restored, run the download-logs tool and consult the error logs it generates. For more information, see the download-logs section below.
• Firewall Rule Change: If your firewall rules change, it might prevent a node from communicating with the rest of the cluster. This causes the node to become unresponsive. In this case, the logs show the node leaving the cluster but do not show network latency errors.
  
  To confirm that the node is unresponsive because of a firewall rule change, SSH from a responsive node to the unresponsive node. If you cannot connect, the node is unresponsive due to a firewall rule change. Change your firewall rules to enable the unresponsive node to rejoin the cluster.
• VM Failure: If you cannot SSH into a node and you are not detecting either network latency or firewall issues, your node might be down due to VM failure. To confirm that the node is unresponsive and re-create the VM, see Re-create a Corrupted VM in a Highly Available below.
• Node Unable to Rejoin: If a detached existing node fails to join the cluster, its sequence_number might be higher than those of the nodes with quorum. A higher sequence_number on the detached node indicates that it has recent changes to the data that the primary component lacks. You can check this by looking at the node’s error log at /var/vcap/sys/log/pxc-mysql/mysql.err.log.
  
  To restore the cluster, do one the following:
  • If the detached node has a higher sequence number than the primary component, do the procedures in Bootstrapping.
  • If bootstrapping does not restore the cluster, you can manually force the node to rejoin the cluster. This removes all of the unsynchronized data from the detached server node and creates a new copy of the cluster data on the node. For more information, see Force a Node to Rejoin a Highly Available Cluster Manually below.

    Warning: Forcing a node to rejoin the cluster is a destructive procedure. Only do this procedure with the assistance of Pivotal Support.

Many Replication Errors in Logs for Highly Available Clusters

This problem happens when there are errors in SQL statements.

Symptom

You see many replication errors in the MySQL logs, like the following:

  160318 9:25:16 [Warning] WSREP: RBR event 1 Query apply warning: 1, 16992456
160318 9:25:16 [Warning] WSREP: Ignoring error for TO isolated action: source: abcd1234-abcd-1234-abcd-1234abcd1234 version: 3 local: 0 state: APPLYING flags: 65 conn_id: 246804 trx_id: -1 seqnos (l: 865022, g: 16992456, s: 16992455, d: 16992455, ts: 2530660989030983)
160318 9:25:16 [ERROR] Slave SQL: Error 'Duplicate column name 'number'' on query. Default database: 'cf_0123456_1234_abcd_1234_abcd1234abcd'. Query: 'ALTER TABLE ...'

Explanation and Solution

For solutions for replication errors in MySQL log files, see the table below.

If you see replication errors, but no ALTER TABLE or persistent disk or memory issues, you can ignore the replication errors.

Troubleshooting Components

This section provides guidance on checking for and fixing issues in on-demand service components.

BOSH Problems

Large BOSH Queue

On-demand service brokers add tasks to the BOSH request queue, which can back up and cause delay under heavy loads. An app developer who requests a new MySQL for PCF instance sees create in progress in the Cloud Foundry Command Line Interface (cf CLI) until BOSH processes the queued request.

Ops Manager currently deploys two BOSH workers to process its queue. Future versions of Ops Manager will let users configure the number of BOSH workers.

Configuration

Service instances in failing state

You may have configured a VM / Disk type in tile plan page in Ops Manager that is insufficiently large for the MySQL for PCF service instance to start. See tile-specific guidance on resource requirements.

Authentication

UAA Changes

If you have rotated any UAA user credentials then you may see authentication issues in the service broker logs.

To resolve this, redeploy the MySQL for PCF tile in Ops Manager. This provides the broker with the latest configuration.

Note: You must ensure that any changes to UAA credentials are reflected in the Ops Manager credentials tab of the Pivotal Application Service tile.

Networking

Common issues with networking include:

Validate Service Broker Connectivity to Service Instances

To validate connectivity, do the following:

1. To SSH into the MySQL for PCF service broker, run the following command:

   bosh -d service-instance_GUID ssh

2. If no BOSH task-id appears in the error message, look in the broker log using the broker-request-id from the task.

Validate App Access to Service Instance

Use cf ssh to access to the app container, then try connecting to the MySQL for PCF service instance using the binding included in the VCAP_SERVICES environment variable.

Quotas

Plan Quota Issues

If developers report errors such as:

Message: Service broker error: The quota for this service plan has been exceeded.
Please contact your Operator for help.

1. Check your current plan quota.
2. Increase the plan quota.
3. Log into Ops Manager.
4. Reconfigure the quota on the plan page.
5. Deploy the tile.
6. Find who is using the plan quota and take the appropriate action.

Global Quota Issues

If developers report errors such as:

Message: Service broker error: The quota for this service has been exceeded.
Please contact your Operator for help.

1. Check your current global quota.
2. Increase the global quota.
3. Log into Ops Manager.
4. Reconfigure the quota on the on-demand settings page.
5. Deploy the tile.
6. Find out who is using the quota and take the appropriate action.

Failing Jobs and Unhealthy Instances

To determine whether there is an issue with the MySQL for PCF service deployment, inspect the VMs. To do so, run the following command:

bosh -d service-instance_GUID vms --vitals

For additional information, run the following command:

bosh instances --ps --vitals

If the VM is failing, follow the service-specific information. Any unadvised corrective actions (such as running BOSH restart on a VM) can cause issues in the service instance.

A failing process or failing VM might come back automatically after a temporary service outage. See VM Process Failure and VM Failure.

AZ or Region Failure

Failures at the IaaS level, such as Availability Zone (AZ) or region failures, can interrupt service and require manual restoration. See AZ Failure and Region Failure.

Techniques for Troubleshooting

Instructions on interacting with the on-demand service broker and on-demand service instance BOSH deployments, and on performing general maintenance and housekeeping tasks

Parse a Cloud Foundry (CF) Error Message

Failed operations (create, update, bind, unbind, delete) result in an error message. You can retrieve the error message later by running the cf CLI command cf service INSTANCE-NAME.

$ cf service myservice

Service instance: myservice
Service: super-db
Bound apps:
Tags:
Plan: dedicated-vm
Description: Dedicated Instance
Documentation url:
Dashboard:

Last Operation
Status: create failed
Message: Instance provisioning failed: There was a problem completing your request.
     Please contact your operations team providing the following information:
     service: redis-acceptance,
     service-instance-guid: ae9e232c-0bd5-4684-af27-1b08b0c70089,
     broker-request-id: 63da3a35-24aa-4183-aec6-db8294506bac,
     task-id: 442,
     operation: create
Started: 2017-03-13T10:16:55Z
Updated: 2017-03-13T10:17:58Z

Use the information in the Message field to debug further. Provide this information to Pivotal Support when filing a ticket.

The task-id field maps to the BOSH task ID. For more information on a failed BOSH task, use the bosh task TASK-ID.

The broker-request-guid maps to the portion of the On-Demand Broker log containing the failed step. Access the broker log through your syslog aggregator, or access BOSH logs for the broker by typing bosh logs broker 0. If you have more than one broker instance, repeat this process for each instance.

Access Broker and Instance Logs and VMs

Before following the procedures below, log into the cf CLI and the BOSH CLI.

Access Broker Logs and VM(s)

You can access logs using Ops Manager by clicking on the Logs tab in the tile and downloading the broker logs.

To access logs using the BOSH CLI, do the following:

1. Identify the on-demand broker (ODB) deployment by running the following command:

   bosh deployments

2. View VMs in the deployment by running the following command:

   bosh -d DEPLOYMENT-NAME instances

3. SSH onto the VM by running the following command:

   bosh -d service-instance_GUID ssh

4. Download the broker logs by running the following command:

   bosh -d service-instance_GUID logs

The archive generated by BOSH or Ops Manager includes the following logs:

Access Service Instance Logs and VMs

1. To target an individual service instance deployment, retrieve the GUID of your service instance with the following cf CLI command:

   cf service MY-SERVICE --guid

2. To view VMs in the deployment, run the following command:

   bosh -d DEPLOYMENT-NAME instances

3. To SSH into a VM, run the following command:

   bosh -d service-instance_GUID ssh

4. To download the instance logs, run the following command:

   bosh -d service-instance_GUID logs

Retrieve Admin and Read-Only Admin Credentials for a Service Instance

To retrieve the admin and read-only admin credentials for a service instance from BOSH CredHub, perform the following steps:

1. Use the cf CLI to determine the GUID associated with the service instance for which you want to retrieve credentials. Run the following command:

   cf service service-instance --guid

   
   Where SERVICE-INSTANCE is the name of the service instance.
   
   For example:

   $ cf service my-service-instance --guid
       12345678-90ab-cdef-1234-567890abcdef

   If you do not know the name of the service instance, you can list service instances in the space with cf services.
2. Perform the steps in Gather Credential and IP Address Information and SSH into Ops Manager of Advanced Troubleshooting with the BOSH CLI to SSH into the Ops Manager VM.
3. From the Ops Manager VM, log in to your BOSH Director with the BOSH CLI. See Log in to the BOSH Director in Advanced Troubleshooting with the BOSH CLI.
4. Follow the steps in Find the CredHub Credentials, and record the values for identity and password.
5. Set the API target of the CredHub CLI to your BOSH CredHub server.
   
   Run the following command:

   credhub api https://BOSH-DIRECTOR:8844 --ca-cert=/var/tempest/workspaces/default/root_ca_certificate

   
   Where BOSH-DIRECTOR is the IP address of the BOSH Director VM.
   
   For example:

   $ credhub api https://10.0.0.5:8844 --ca-cert=/var/tempest/workspaces/default/root_ca_certificate

6. Log in to CredHub.
   
   Run the following command:

   credhub login \
       --client-name=CREDHUB-CLIENT-NAME \
       --client-secret=CREDHUB-CLIENT-SECRET

   Where:
   • CREDHUB-CLIENT-NAME is the identity you recorded in Find the CredHub Credentials.
   • CREDHUB-CLIENT-SECRET is the password you recorded in Find the CredHub Credentials.
   For example:

   $ credhub login \
         --client-name=credhub \
         --client-secret=abcdefghijklm123456789

7. Use the CredHub CLI to retrieve the credentials.
   • To retrieve the password for the admin user, run the following command:

     credhub get -n /p-bosh/service-instance_guid/admin_password

     In the output, the password appears under value.
   
   
   • To retrieve the password for the read-only admin user, run the following command:

     credhub get -n /p-bosh/service-instance_guid/read_only_admin_password

     In the output, the password appears under value.
   
   For example:

   $ credhub get -n /p-bosh/service-instance_70d30bb6-7f30-441a-a87c-05a5e4afff26/admin_password
       id: d6e5bd10-3b60-4a1a-9e01-c76da688b847
       name: /p-bosh/service-instance_70d30bb6-7f30-441a-a87c-05a5e4afff26/admin_password
       type: password
       value: UMF2DXsqNPPlCNWMdVMcNv7RC3Wi10
       version_created_at: 2018-04-02T23:16:09Z

Reinstall a Tile

To reinstall the MySQL for PCF tile, see Reinstalling MySQL for Pivotal Cloud Foundry version 2 and above in the Pivotal Support knowledge base.

View Resource Saturation and Scaling

To view usage statistics for any service, do the following:

1. Run the following command:

   bosh -d DEPLOYMENT-NAME vms --vitals

2. To view process-level information, run:

   bosh -d DEPLOYMENT-NAME instances --ps

Identify Service Instance Owner

If you want to identify which apps are using a specific service instance from the BOSH deployments name, do the following:

1. Take the deployment name and strip the service-instance_ leaving you with the GUID.
2. Log in to CF as an admin.
3. Obtain a list of all service bindings by running the following:

   cf curl /v2/service_instances/GUID/service_bindings

4. The output from the above curl gives you a list of resources, with each item referencing a service binding, which contains the APP-URL. To find the name, org, and space for the app, run the following:
   1. cf curl APP-URL and record the app name under entity.name.
   2. cf curl SPACE-URL to obtain the space, using the entity.space_url from the above curl. Record the space name under entity.name.
   3. cf curl ORGANIZATION-URL to obtain the org, using the entity.organization_url from the above curl. Record the organization name under entity.name.

Note: When running cf curl ensure that you query all pages, because the responses are limited to a certain number of bindings per page. The default is 50. To find the next page curl the value under next_url.

Monitor Quota Saturation and Service Instance Count

Quota saturation and total number of service instances are available through ODB metrics emitted to Loggregator. The metric names are shown below:

Note: Quota metrics are not emitted if no quota has been set.

Techniques for Troubleshooting Highly Available Clusters

If your cluster is experiencing downtime or in a degraded state, Pivotal recommends gathering information to diagnose the type of failure the cluster is experiencing with the following workflow:

1. Consult solutions for common errors. See Highly Available Cluster Troubleshooting Errors above.
2. Use mysql-diag to view a summary of the network, disk, and replication state of each cluster node. Depending on the output from mysql-diag, you might recover your cluster with the following troubleshooting techniques:
   • To force a node to rejoin the cluster, see Force a Node to Rejoin a Highly Available Cluster Manually below.
   • To re-create a corrupted VM, see Re-create a Corrupted VM in a Highly Available Cluster below.
   • To check if replication is working, see Check Replication in a Highly Available Cluster below.
   For more information about mysql-diag, see Running mysql-diag.
3. Run download-logs against each node in your MySQL cluster, MySQL proxies, and jumpbox VM. You must run download-logs before attempting recovery because any failures in the recovery procedure can result in logs being lost or made inaccessible.
   For more information, see the download-logs section below.
   

   Note: Pivotal recommends that you use the -X flag to get the complete set of available logs. However, if your cluster processes a high volume of transactions, the complete set might be too large and you can omit this flag to fetch the essential set of logs.

4. If you are uncertain about the recovery steps to take, submit a ticket through Pivotal Support. When you submit a ticket provide the following information:
   • mysql-diag output: A summary of the network, disk, and replication state. The Running mysql-diag topic explains how to run mysql-diag.
   • download-logs logs: Logs from your MySQL cluster, MySQL proxies, and jumpbox VM. The download-logs section below explains how to run download-logs.
   • Deployment environment: The environment that MySQL for PCF is running in such as Pivotal Application Service (PAS) or a service tile.
   • Version numbers: The versions of the installed Ops Manager, PAS, and MySQL for PCF

Warning: Do not attempt to resolve cluster issues by reconfiguring the cluster, such as changing the number of nodes or networks. Only follow the diagnosis steps in this document. If you are unsure how to proceed, contact Pivotal Support.

Force a Node to Rejoin a Highly Available Cluster Manually

If a detached node fails to rejoin the cluster after a configured grace period, you can manually force the node to rejoin the cluster. This procedure removes all the data on the node, forces the node to join the cluster, and creates a new copy of the cluster data on the node.

Warning: If you manually force a node to rejoin the cluster, data stored on the local node is lost. Do not force nodes to rejoin the cluster if you want to preserve unsynchronized data. Only do this procedure with the assistance of Pivotal Support.

Before following this procedure, try to bootstrap the cluster. For more information, see Bootstrapping.

To manually force a node to rejoin the cluster, do the following:

1. To SSH into the node, follow the procedure in BOSH SSH.
2. To become root, run the following command:

    sudo su

3. To shut down the mysqld process on the node, run the following command:

     monit stop galera-init 

4. To remove the unsynchronized data on the node, run the following command:

     rm -rf /var/vcap/store/pxc-mysql

5. To prepare the node before restarting, run the following command:

     /var/vcap/jobs/pxc-mysql/bin/pre-start

6. To restart the mysqld process, run the following command:

    monit start galera-init

Re-create a Corrupted VM in a Highly Available Cluster

To re-create a corrupted VM, do the following:

1. To log in to the BOSH Director VM, do the following procedures:
   1. To gather the information needed to log in to the BOSH Director VM, see Gather Credential and IP Address Information.
   2. To log in to the Ops Manager VM, see Log in to the Ops Manager VM with SSH.
   3. To log in to the BOSH Director VM, see Log in to the BOSH Director VM.
2. To identify and re-create the unresponsive node with bosh cloudcheck, do the procedure in BOSH Cloudcheck and run Recreate VM using last known apply spec.

   Warning: Recreating a node will clear its logs. Ensure the node is completely down before recreating it.

   Warning: Only re-create one node. Do not re-create the entire cluster. If more than one node is down, contact Pivotal Support.

Check Replication Status in a Highly Available Cluster

If you see stale data in your cluster, you can check whether replication is functioning normally.

To check the replication status, do the following:

1. To log in to the BOSH Director VM, do the following procedures:
   1. To gather the information needed to log in to the BOSH Director VM, see Gather Credential and IP Address Information.
   2. To log in to the Ops Manager VM, see Log in to the Ops Manager VM with SSH.
2. To create a dummy database in the first node, run the following command:

   mysql -h FIRST-NODE-IP-ADDRESS -u YOUR-IDENTITY -p -e "create database verify_healthy;"

   Where:
   • FIRST-NODE-IP-ADDRESS is the IP address of the first node you recorded in step 1.
   • YOUR-IDENTITY is the value of identity that you recorded in step 1.
3. To create a dummy table in the dummy database, do the following:

   mysql -h FIRST-NODE-IP-ADDRESS -u YOUR-IDENTITY -p -D verify_healthy -e "create table dummy_table (id int not null primary key auto_increment, info text) engine='innodb';"

4. To insert data into the dummy table, run the following command:

   mysql -h FIRST-NODE-IP-ADDRESS -u YOUR-IDENTITY -p -D verify_healthy -e "insert into dummy_table(info) values ('dummy data'),('more dummy data'),('even more dummy data');"

5. To query the table and verify that the three rows of dummy data exist on the first node, run the following:

   mysql -h FIRST-NODE-IP-ADDRESS -u YOUR-IDENTITY -p -D verify_healthy -e "select * from dummy_table;"

   When prompted for a password, provide the password value recorded in step 1.
   The above command returns output similar to the following:

     +----+----------------------+
     | id | info                 |
     +----+----------------------+
     |  4 | dummy data           |
     |  7 | more dummy data      |
     | 10 | even more dummy data |
     +----+----------------------+

6. To verify that the other nodes contain the same dummy data do the following for each of the remaining MySQL server IP addresses:
   • To query the dummy table, do the following:

     mysql -h NEXT-NODE-IP-ADDRESS -u YOUR-IDENTITY -p -D verify\_healthy -e "select * from dummy_table;"

     When prompted for a password, provide the password value recorded in step 1.
   • To verify that the node contains the same three rows of dummy data as the other nodes, run the following command:

     mysql -h NEXT-NODE-IP-ADDRESS -u YOUR-IDENTITY -p -D verify\_healthy -e "select * from dummy\_table;"

     When prompted for a password, provide the password value recorded in step 1. Verify that the above command returns output similar to the following:

         +----+----------------------+
         | id | info                 |
         +----+----------------------+
         |  4 | dummy data           |
         |  7 | more dummy data      |
         | 10 | even more dummy data |
         +----+----------------------+ 

7. If each MySQL server instance does not return the same result, before proceeding further or making any changes to your deployment, contact Pivotal Support
   If each MySQL server instance returns the same result, then you can safely proceed to scaling down your cluster to a single node.

Tools for Troubleshooting

The troubleshooting techniques described above use the following tools.

download-logs

download-logs is a script that you can run from your Ops Manager VM to aggregate logs from your MySQL cluster nodes, MySQL proxies, and, with highly available clusters, the jumpbox VM. Do the following to run the download-logs script:

1. Download and unpack the download-logs script from MySQL for PCF on Pivotal Network.

2. From Ops Manager, open your BOSH Director tile > Credentials tab.

3. Click Bosh Commandline Credentials > Link to Credential. A short plaintext file opens.

4. From the plaintext file, record the values listed for the following:

   • BOSH_CLIENT
   • BOSH_CLIENT_SECRET
   • BOSH_CA_CERT
   • BOSH_ENVIRONMENT

5. From the BOSH CLI, run bosh deployments and record the name of the BOSH deployment that deployed MySQL for PCF.

6. SSH into your Ops Manager VM. For information on how to do this, see Gather Credential and IP Address Information and SSH into Ops Manager.

7. File transfer or copy-paste the download-logs script to a working directory on the Ops Manager VM.

8. Set local environment variables to the same BOSH variable values that you recorded earlier, including BOSH_DEPLOYMENT for the deployment name. For example:

   $ BOSH_CLIENT=ops_manager BOSH_CLIENT_SECRET=a123bc-E_4Ke3fb-gImbl3xw4a7meW0rY BOSH_CA_CERT=/var/tempest/workspaces/default/root_ca_certificate BOSH_ENVIRONMENT=10.0.0.5 BOSH_DEPLOYMENT=pivotal-mysql-14c4

9. Run the download-logs script, passing the output directory to the -o flag:

   ./download-logs -o .
   

10. The script saves a compressed file of logs combined from all MySQL VMs. The filename has the form TIMESTAMP-mysql-logs.tar.gz.gpg.

mysql-diag

mysql-diag outputs the current status of a highly available (HA) MySQL cluster in PCF and suggests recovery actions if the cluster fails. For more information, see Running mysql-diag.

Knowledge Base (Community)

Find the answer to your question and browse product discussions and solutions by searching the Pivotal Knowledge Base.

File a Support Ticket

You can file a ticket with Pivotal Support. Be sure to provide the error message from cf service YOUR-SERVICE-INSTANCE.

To expedite troubleshooting, provide your service broker logs and your service instance logs. If your cf service YOUR-SERVICE-INSTANCE output includes a task-id, provide the BOSH task output.