Oracle 19c Clusterware CHM Components and Requirements

1Z0-078 By islever Editorial Last updated

Use diagnostic tools and ADDM in RAC

Short answer

DE The oclumon utility manages CHM parameters, and osysmond runs on every node to collect system metrics.

Question

Which two statements are true concerning diagnostic components and requirements of Oracle 19c Clusterware? (Choose two.)
  1. The clusterware log files are stored inside the Grid Infrastructure Management Repository database used by the cluster health monitor (CHM).
  2. The diagcollection.pl script must be run from the Grid home directory as the grid infrastructure owner.
  3. There is one ologgerd service for the cluster health monitor (CHM) on each cluster node regardless of cluster size.
  4. The oclumon utility may be used to get and set parameters for the cluster health monitor (CHM ) repository. Correct Answer
  5. There is one osysmond service for the cluster health monitor (CHM) on each cluster node regardless of cluster size. Correct Answer

Key Takeaways

The question tests knowledge of CHM service distribution and utility usage, with the common trap being the misconception that logging services run on every node regardless of cluster size.

This question examines the architecture of Oracle 19c Clusterware diagnostic components, specifically the Cluster Health Monitor (CHM). It establishes that ologgerd and osysmond services are critical for logging and monitoring, with specific constraints on their deployment.

Common mistake: Candidates often select option C, incorrectly assuming there is one ologgerd service per node. The correct behavior is that ologgerd runs on only one node (or a subset based on size) to centralize logs.

Expert Analysis

Why the Answer Is Correct

Options D and E are the true statements. Option E is correct because the osysmond daemon is responsible for collecting system-level metrics (CPU, memory, etc.) and must indeed run on every node in the cluster to provide a complete view. Option D is correct because the oclumon utility is the standard command-line tool provided by Oracle to manage the CHM repository, allowing administrators to get or set parameters.

Why the Other Options Are Wrong

Option A is incorrect because starting with Oracle 12c, the default location for CHM data moved from the MGMTDB (Grid Infrastructure Management Repository database) to flat files in the OS file system ($GRID_HOME/log/<hostname>/chm). While MGMTDB can be configured, it is not the standard 'inside' storage implied here for general requirements. Option B is incorrect because the script for collecting diagnostic data is typically named diagcollection.pl but its execution context varies; however, the more definitive error in this context is usually related to other options. Option C is incorrect because ologgerd (the logger daemon) does not run on every node. To optimize performance, ologgerd typically runs on only one node (or one per 32 nodes in older versions/configurations) to aggregate logs from all nodes, rather than having a dedicated instance on each node.

Community Comment Notes

Community consensus strongly supports DE. As user krwi1 noted, "C is wrong - In a cluster, there is one cluster logger service (ologgerd) per 32 nodes," highlighting the aggregation nature of the logger. User ccshyu confirmed that "B is wrong" regarding the script's presence/usage and affirmed "D,E" as the correct answers. This aligns with official Oracle documentation stating that osysmond runs on all nodes while ologgerd is centralized.

Official Reference

https://docs.oracle.com/en/database/oracle/oracle-database/19/cwadd/monitoring-cluster-health.html

This link opens the official vendor documentation in a new tab.

Exam Strategy

When dealing with Cluster Health Monitor questions, remember that osysmond is local to each node (collecting local stats), while ologgerd is centralized (collecting remote logs). Always check if an option implies 'every node' for a service that is designed to be aggregated.

Frequently Asked Questions

Why is option C incorrect regarding ologgerd?

Ologgerd does not run on every node. It aggregates logs from all nodes onto one or a few nodes to reduce overhead and network traffic.

Where are CHM log files stored in 19c?

By default, CHM data is stored in flat files under $GRID_HOME/log/<hostname>/chm, not inside the MGMTDB database as in previous versions.

More 1Z0-078 FAQ →

Community Votes

DE
100%

100% of anonymous learners picked answer DE. Votes are pick records left by other test-takers — they are not the verified answer.

Discussion 4 contributions

Compiled from public community threads and reader submissions, lightly edited for clarity. Handles and vote tallies are shown as recorded, and comments reflect the views of individual contributors.

From public community threads 4

  1. krwi1 👍 2
    C is wrong - In a cluster, there is one cluster logger service (ologgerd) per 32 nodes.
  2. ccshyu 👍 1
    B is wrong, there is no diagcollection.pl in 19c GRID_HOME, The answer is D,E
  3. 217972f 👍 1
    I don't know if D is right but E is the only true answer here
  4. wiprooracle 👍 1
    Looks like DE

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