EX436 Red Hat Certified Specialist in High Availability Clustering exam Practice Questions
Prepare for EX436 with more than an answer.
- Time limit
- 180 minutes
- Level
- Specialist (counts toward Red Hat Certified Architect / RHCA)
- Valid for
- See Red Hat Certification renewal policy (https://www.redhat.com/en/services/certification/renewal). Not asserted here to avoid fabrication.
Domains covered on the exam 8
- Configure a high-availability cluster
- Configure cluster fencing
- Configure cluster logging and monitoring
- Configure cluster monitoring
- Configure a clustered fail-over service
- Configure cluster service behavior
- Configure storage
- Configure GFS2 filesystems
- 1
After configuring a new STONITH device, you want to manually verify that the cluster can successfully execute a fencing action against
node2. Which command securely triggers this test through the Pacemaker infrastructure?Show answer details
Correct answer: B
The
pcs stonith fencecommand is the standard and safest way to manually test fencing. It requests Pacemaker to fence the target node using the configured STONITH topology, verifying the entire fencing stack. - 2
In a two-node cluster, a severe network interruption occurs, and both nodes attempt to fence each other simultaneously. To prevent a 'fencing loop' where both nodes reboot each other, you decide to configure one node to wait slightly before executing its fencing action. Which parameter should you apply to the STONITH device?
Show answer details
Correct answer: B
The
pcmk_delay_maxparameter introduces a random delay (up to the specified maximum) before executing a fencing action. This breaks the tie in a two-node split-brain scenario, ensuring one node survives while the other is fenced. - 3
Which configuration file is primarily responsible for dictating how the underlying Corosync cluster engine logs its internal operational events and debug messages?
Show answer details
Correct answer: B
The
/etc/corosync/corosync.conffile contains thelogging { ... }stanza, which controls where Corosync sends its logs (syslog, logfile, stderr) and at what debug level. - 4
You want to ensure that all Corosync logging messages are forwarded directly to systemd's journal instead of a traditional flat file. Which directive must be set in the
loggingstanza of the cluster configuration?Show answer details
Correct answer: B
In modern RHEL distributions, setting
to_syslog: yesincorosync.confforwards the logs to the local syslog facility, which is captured and managed by systemd'sjournaldby default. - 5
As a system administrator for NovaTech, you are deploying a new Red Hat Enterprise Linux (RHEL) High Availability cluster. Before creating the cluster, you must authenticate the nodes so that the
pcscommand can communicate with thepcsddaemon across all systems. Which command is the correct standard method in RHEL 8/9 to accomplish this?Show answer details
Correct answer: B
In RHEL 8 and 9, the command to authenticate nodes for the
pcsddaemon ispcs host auth. The older syntax (pcs cluster auth) was deprecated and replaced to better reflect that the authentication happens at the host level before the cluster is formally created. - 6
You are automating the deployment of a Pacemaker cluster using the Red Hat Enterprise Linux
ha_clusterAnsible system role. Which TWO variables must be defined in your playbook to successfully set the cluster name and the authentication password for thehaclusteruser? (Select TWO)Show answer details
Correct answer: B, D
The
ha_clustersystem role uses specific variable naming conventions.ha_cluster_cluster_nameis required to define the name of the Corosync cluster.The
ha_cluster_hacluster_passwordvariable is explicitly used by theha_clusterrole to set the password for thehaclusteruser on all nodes, which is necessary forpcsdauthentication.
