Catalog Daemon Statestore Subscriber Test

In Catalog Daemon server, the Statestore Subscriber communicates with Catalog Daemon periodically through the exchange of topic update messages. These messages contain updates from the statestore to a list of 'topics' that the subscriber is interested in; in response the subscriber sends a list of changes that it wishes to make to a topic. The statestore also sends more frequent 'heartbeat' messages that confirms an active connection between Statestore Subscriber and Catalog Daemon.

The Catalog Daemon Statestore Subscriber test monitors the heartbeat intervals, update time, processing time etc. This test checks for latencies in all communications initiated by the Statestore, so that slowness can be promptly captured, and where exactly the slowness has occurred can be determined.

Target of the test : Apache Impala

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for the target Catalog Daemon server.

Configurable parameters for the test
Parameter Description

Test period

How often should the test be executed.

Host

The IP address of the target server that is being monitored.

Port

The port number through which the Apache Impala communicates. The default port is 25000.

Impalad URL

Each daemon server has a different endpoint URL. You need to configure the eG agent with the endpoint URL of each daemon, so that the agent can access the URL and pull metrics on the health of the target daemon servers. Specify such URL in the Impalad URL text box . To know how to configure the eG agent with the API Endpoint URLs, refer to Configuring the eG agent with the API Endpoint URLs topic in Pre-requisites for Monitoring Apache Impala.

Impalad Authorization type

To access daemon server, you need to configure Digest authorization. Digest authorization is a method used to verify the identity of a user requesting access to API Endpoint URL of the daemon server. Digest authorization uses a combination of a username, password, and a unique message digest (a type of encrypted code). Specify such Digest authorization value in the Impalad Authorization type text box considering the below criteria:

  • If an Impalad URL is password protected (i.e., username and password configured through Cloudera Manager), then specify the value as digest_auth in the Impalad Authorization type text box. Here, digest_auth stands for Digest Authorization

  • If an Impalad URL is not password protected, then specify the value as no_auth in the Impalad Authorization type text box. Here, no_auth stands for No Authorization.

If multiple Impalad URLs are mentioned in the Impalad URL text box, then specify a comma-separated list of authorization type for each URL. For example, if there are two Impalad URLs, one URL without authorization and the other URL protected with authorization (username/password authorization), then specify Impalad Authorization type as: no_auth,digest_auth in the Impalad Authorization type text box. By default, Impalad Authorization type value is no_auth.

Impalad User, Impalad Password and Confirm Password

Once you enable web server access to the eG agent, make sure that 'password authentication' is also enabled. This is needed, so that the eG agent is able to access the built-in web server for each daemon in a safe, secure manner. Configure the credentials of such a user against Impalad User and Password text boxes. Confirm the password by retyping it in the Confirm Password text box. To know how to configure the eG agent with 'secure' access to the built-in web server, refer to Configuring the eG agent with 'secure' access to the built-in web server topic in Pre-requisites for Monitoring Apache Impala.

By default, Impalad user parameter is set to none.

  • If an Impalad URL is password protected (i.e., username and password configured through Cloudera Manager), then specify the configured username in the Impalad User text box.

  • If an Impalad URL is not password protected, then specify the value as none in the Impalad User text box.

  • An Impala daemon server can have multiple IP addresses. In this case, specify the corresponding URL parameter with a comma-separated list of endpoint URLs in the Impalad User textbox.

Statestored URL

Each daemon server has a different endpoint URL. You need to configure the eG agent with the endpoint URL of each daemon, so that the agent can access the URL and pull metrics on the health of the target daemon servers. Specify such URL in the Statestored URL text box . To know how to configure the eG agent with the API Endpoint URLs, refer to Configuring the eG agent with the API Endpoint URLs topic in Pre-requisites for Monitoring Apache Impala.

Statestored Authorization type

To access daemon server, you need to configure Digest authorization. Digest authorization is a method used to verify the identity of a user requesting access to API Endpoint URL of the daemon server. Digest authorization uses a combination of a username, password, and a unique message digest (a type of encrypted code). Specify such Digest authorization value in the Statestored Authorization type text box considering the below criteria:

  • If a Statestored URL is password protected (i.e., username and password configured through Cloudera Manager), then specify the value as digest_auth in the Statestored Authorization type text box. Here, digest_auth stands for Digest Authorization

  • If an Statestored URL is not password protected, then specify the value as no_auth in the Statestored Authorization type text box. Here, no_auth stands for No Authorization.

By default, Statestored Authorization type value is no_auth.

Statestored User, Statestored Password and Confirm Password

Once you enable web server access to the eG agent, make sure that 'password authentication' is also enabled. This is needed, so that the eG agent is able to access the built-in web server for each daemon in a safe, secure manner. Configure the credentials of such a user against Statestored User and Password text boxes. Confirm the password by retyping it in the Confirm Password text box. To know how to configure the eG agent with 'secure' access to the built-in web server, refer to Configuring the eG agent with 'secure' access to the built-in web server topic in Pre-requisites for Monitoring Apache Impala.

By default, Impalad user parameter is set to none.

  • If a Statestored URL is password protected (i.e., username and password configured through Cloudera Manager), then specify the configured username in the Statestored User text box.

  • If a Statestored URL is not password protected, then specify the value as none in the Statestored User text box.

Catalogd URL

Each daemon server has a different endpoint URL. You need to configure the eG agent with the endpoint URL of each daemon, so that the agent can access the URL and pull metrics on the health of the target daemon servers. Specify such URL in the Catalogd URL text box . To know how to configure the eG agent with the API Endpoint URLs, refer to Configuring the eG agent with the API Endpoint URLs topic in Pre-requisites for Monitoring Apache Impala.

Catalogd Authorization type

To access daemon server, you need to configure Digest authorization. Digest authorization is a method used to verify the identity of a user requesting access to API Endpoint URL of the daemon server. Digest authorization uses a combination of a username, password, and a unique message digest (a type of encrypted code). Specify such Digest authorization value in the Catalogd Authorization type text box considering the below criteria:

  • If a Catalogd URL is password protected (i.e., username and password configured through Cloudera Manager), then specify the value as digest_auth in the Catalogd Authorization type text box. Here, digest_auth stands for Digest Authorization

  • If an Catalogd URL is not password protected, then specify the value as no_auth in the Catalogd Authorization type text box. Here, no_auth stands for No Authorization.

By default, Statestored Authorization type value is no_auth.

Catalogd User, Catalogd Password and Confirm Password

Once you enable web server access to the eG agent, make sure that 'password authentication' is also enabled. This is needed, so that the eG agent is able to access the built-in web server for each daemon in a safe, secure manner. Configure the credentials of such a user against Catalogd User and Password text boxes. Confirm the password by retyping it in the Confirm Password text box. To know how to configure the eG agent with 'secure' access to the built-in web server, refer to Configuring the eG agent with 'secure' access to the built-in web server topic in Pre-requisites for Monitoring Apache Impala.

By default, Impalad user parameter is set to none.

  • If a Catalogd URL is password protected (i.e., username and password configured through Cloudera Manager), then specify the configured username in the Catalogd User text box.

  • If a Catalogd URL is not password protected, then specify the value as none in the Catalogd User text box.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Is connected?

Indicates whether/not this Catalog daemon is connected to the StateStore.

 

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure Value

 Numeric Value
True 0
False 1

Note:

By default, this measure reports the Measure Values listed in the table above to indicate whether/not the Catalog daemon is connected to the StateStore.

Last recovery duration

Indicates the time that elapsed since the last Statestore recovery happened.

Seconds

If any of these time measures reports an unusually high value, it could indicate that the corresponding activity is sluggish. Administrators should be advised to investigate the slowness.

 

 

 

 

 

Impala request queue processing time

Indicates the Impala request queue processing time for Statestore Subscriber Topic.

Seconds

Impala membership processing time

Indicates the Impala membership processing time for Statestore Subscriber Topic.

Seconds

Catalog update processing time

Indicates the Impala catalog update processing time for Statestore Subscriber Topic.

Seconds

Heartbeat interval time

Indicates the heartbeat interval time for Statestore Subscriber Topic

Seconds

Topic update duration

Indicates the update duration for Statestore Subscriber Topic

Seconds

Topic update interval time

Indicates the update interval time for Statestore Subscriber Topic.

Seconds