Chapter 2. Logging

Red Hat OpenStack Platform writes informational messages to specific log files; you can use these messages for troubleshooting and monitoring system events.


You do not need to attach the individual log files to your support cases manually. All the required information is gathered automatically by the sosreport utility, which is described in Chapter 5, Troubleshooting.

2.1. Log files for OpenStack services

Each OpenStack component has a separate logging directory containing files specific to a running service.

2.1.1. Bare Metal Provisioning (ironic) Log Files

ServiceService NameLog Path

OpenStack Ironic API



OpenStack Ironic Conductor



2.1.2. Block Storage (cinder) Log Files

ServiceService NameLog Path

Block Storage API



Block Storage Backup



Informational messages

The cinder-manage command


Block Storage Scheduler



Block Storage Volume



2.1.3. Compute (nova) Log Files

ServiceService NameLog Path

OpenStack Compute API service



OpenStack Compute certificate server



OpenStack Compute service



OpenStack Compute Conductor service



OpenStack Compute VNC console authentication server



Informational messages

nova-manage command


OpenStack Compute NoVNC Proxy service



OpenStack Compute Scheduler service



2.1.4. Dashboard (horizon) Log Files

ServiceService NameLog Path

Log of certain user interactions

Dashboard interface


The Apache HTTP server uses several additional log files for the Dashboard web interface, which can be accessed using a web browser or command-line clients (keystone, nova). The following log files can be helpful in tracking the usage of the Dashboard and diagnosing faults:

PurposeLog Path

All processed HTTP requests


HTTP errors


Admin-role API requests


Admin-role API errors


Member-role API requests


Member-role API errors



There is also /var/log/containers/httpd/default_error.log, which stores errors reported by other web services running on the same host.

2.1.5. Database as a Service (trove) Log Files

ServiceService NameLog Path

OpenStack Trove API Service



OpenStack Trove Conductor Service



OpenStack Trove guestagent Service



OpenStack Trove taskmanager Service



2.1.6. Identity Service (keystone) Log Files

ServiceService NameLog Path

OpenStack Identity Service



2.1.7. Image Service (glance) Log Files

ServiceService NameLog Path

OpenStack Image Service API server



OpenStack Image Service Registry server



2.1.8. Networking (neutron) Log Files

ServiceService NameLog Path

OpenStack Neutron DHCP Agent



OpenStack Networking Layer 3 Agent



Metadata agent service



Metadata namespace proxy



Open vSwitch agent



OpenStack Networking service



2.1.9. Object Storage (swift) Log Files

OpenStack Object Storage sends logs to the system logging facility only.


By default, all Object Storage log files to /var/log/containers/swift/swift.log, using the local0, local1, and local2 syslog facilities.

The log messages of Object Storage are classified into two broad categories: those by REST API services and those by background daemons. The API service messages contain one line per API request, in a manner similar to popular HTTP servers; both the frontend (Proxy) and backend (Account, Container, Object) services post such messages. The daemon messages are less structured and typically contain human-readable information about daemons performing their periodic tasks. However, regardless of which part of Object Storage produces the message, the source identity is always at the beginning of the line.

An example of a proxy message:

Apr 20 15:20:34 rhev-a24c-01 proxy-server: 20/Apr/2015/19/20/34 GET /v1/AUTH_zaitcev%3Fformat%3Djson%26marker%3Dtestcont HTTP/1.0 200 - python-swiftclient-2.1.0 AUTH_tk737d6... - 2 - txc454fa8ea4844d909820a-0055355182 - 0.0162 - - 1429557634.806570053 1429557634.822791100

An example of ad-hoc messages from background daemons:

Apr 27 17:08:15 rhev-a24c-02 object-auditor: Object audit (ZBF). Since Mon Apr 27 21:08:15 2015: Locally: 1 passed, 0 quarantined, 0 errors files/sec: 4.34 , bytes/sec: 0.00, Total time: 0.23, Auditing time: 0.00, Rate: 0.00
Apr 27 17:08:16 rhev-a24c-02 object-auditor: Object audit (ZBF) "forever" mode completed: 0.56s. Total quarantined: 0, Total errors: 0, Total files/sec: 14.31, Total bytes/sec: 0.00, Auditing time: 0.02, Rate: 0.04
Apr 27 17:08:16 rhev-a24c-02 account-replicator: Beginning replication run
Apr 27 17:08:16 rhev-a24c-02 account-replicator: Replication run OVER
Apr 27 17:08:16 rhev-a24c-02 account-replicator: Attempted to replicate 5 dbs in 0.12589 seconds (39.71876/s)
Apr 27 17:08:16 rhev-a24c-02 account-replicator: Removed 0 dbs
Apr 27 17:08:16 rhev-a24c-02 account-replicator: 10 successes, 0 failures

2.1.10. Orchestration (heat) Log Files

ServiceService NameLog Path

OpenStack Heat API Service



OpenStack Heat Engine Service



Orchestration service events



2.1.11. Shared Filesystem Service (manila) Log Files

ServiceService NameLog Path

OpenStack Manila API Server



OpenStack Manila Scheduler



OpenStack Manila Share Service




Some information from the Manila Python library can also be logged in /var/log/containers/manila/manila-manage.log.

2.1.12. Telemetry (ceilometer) Log Files

ServiceService NameLog Path

OpenStack ceilometer notification agent



OpenStack ceilometer alarm evaluation



OpenStack ceilometer alarm notification



OpenStack ceilometer API



Informational messages

MongoDB integration


OpenStack ceilometer central agent



OpenStack ceilometer collection



OpenStack ceilometer compute agent



2.1.13. Log Files for Supporting Services

The following services are used by the core OpenStack components and have their own log directories and files.

ServiceService NameLog Path

Message broker (RabbitMQ)


/var/log/rabbitmq/rabbit@short_hostname-sasl.log (for Simple Authentication and Security Layer related log messages)

Database server (MariaDB)



Document-oriented database (MongoDB)



Virtual network switch (Open vSwitch)



2.2. Enabling centralized logging during deployment

To enable centralized logging, specify the implementation of the OS::TripleO::Services::Rsyslog composable service. Add the file path of the logging environment file to the overcloud deployment command, as shown in the following example:

openstack overcloud deploy <other arguments>
-e /usr/share/openstack-tripleo-heat-templates/environments/logging-environment-rsyslog.yaml

2.3. Configuring logging features

To configure logging features, modify the RsyslogElasticsearchSetting parameter in the logging-environment-rsyslog.yaml file:

  1. Copy the tripleo-heat-templates/environments/logging-environment-rsyslog.yaml file to your home directory.
  2. Create entries in the RsyslogElasticsearchSetting parameter to suit your environment. The following snippet is an example configuration of the RsyslogElasticsearchSetting parameter:
        server: "exampleip:9200"
        usehttps: "on"

You can configure the RsyslogElasticsearchTls parameters to enable secure data transfer. For more information, see Section 2.3.1, “Configurable parameters”.

2.3.1. Configurable parameters

The following table contains descriptions of the parameters that you can configure. You can find these parameters in the tripleo-heat-templates/deployment/logging/rsyslog-container-puppet.yaml file.



Configuration for rsyslog-elasticsearch plug-in. For more information, see


Contains content of the CA cert for the CA that issued Elasticsearch server cert.


Contains content of the client cert for doing client cert auth against Elasticsearch.


Contains content of the private key corresponding to the cert RsyslogElasticsearchTlsClientCert.

2.4. Overriding the default path for a log file

If you modify the default containers and the modification includes the path to the service log file, you must also modify the default log file path. Every composable service has a default log file path parameter with the naming convention format: <service_name>LoggingSource. For example, the parameter for nova-compute service is NovaComputeLoggingSource. To override the default path for the nova-compute service, add the path to the NovaComputeLoggingSource parameter in your configuration file.

      tag: openstack.nova.compute
      file: /some/other/path/nova-compute.log

The tag and path attributes are mandatory elements of the <service_name>LoggingSource parameter. On each service, the tag and the path are defined and the rest of the values are derived by default. The following snippet is another example of overriding the default log file path:

    tag: openstack.Service
    file: /another/path/service/service.log
    startmsg.regex: "^[a-zA-Z]{3} [0-9]{2} [:0-9]{8}"

2.5. Configuring logging options

Each component maintains distinct logging configuration in the component configuration file. For example, in Compute, these options are set in /etc/nova/nova.conf:

  • To increase the level of informational logging, enable debugging. This option increases the amount of information captured, so consider using it temporarily or first reviewing your log rotation settings.

  • Enable verbose logging:

  • Change the log file path:

  • Send your logs to a central syslog server:


You can also configure the timestamp and format of the logs. Review the configuration file of the component for additional logging options.

2.6. Testing the connection

On the client side, to verify communication between Rsyslog and Elasticsearch, complete the following step:

  1. Navigate to the Elasticsearch connection log file, /var/log/rsyslog/omelasticsearch.log in the Rsyslog container or /var/log/containers/rsyslog/omelasticsearch.log on the host. If this log file does not exist or if the log file exists but does not contain logs, there is no connection problem. If the log file is present and contains logs, Rsyslog has not connected successfully.

To test the connection from the server side, view the Elasticsearch logs for connection issues.

2.7. Server-side logging

If you have an Elasticsearch cluster running, configure the RsyslogElasticsearchSetting parameter in the logging-environment-rsyslog.yaml file to connect Rsyslog that is running on overcloud nodes. To configure the RsyslogElasticsearchSetting parameter, see

2.8. Tracebacks

When you encounter an issue and you start troubleshooting, you can use a traceback log to diagnose the issue. In log files, tracebacks usually have several lines of information, all relating to the same issue. Rsyslog provides a regular expression to define how a log record starts. Each log record usually starts with a timestamp and the first line of the traceback is the only line that contains this information. Rsyslog bundles the indented records with the first line and sends them as one log record. For that behaviour configuration option startmsg.regex in <Service>LoggingSource is used. The following regular expression is the default value for all <service>LoggingSource parameters in the director:

startmsg.regex='^[0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2}(.[0-9]+ [0-9]+)? (DEBUG|INFO|WARNING|ERROR) '

When this default does not match log records of your added or modified LoggingSource, you must change startmsg.regex accordingly.