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name: ibm-websphere description: Use when installing, configuring, or managing IBM WebSphere Application Server on RHEL 9 — WAS traditional (8.5.5/9.0) profiles and deployment, WebSphere Liberty/Open Liberty configuration and development, application deployment (WAR/EAR), security (SSL/TLS, LTPA, LDAP/AD integration, SAML/OIDC), JVM tuning (heap, GC policies), clustering and ND topology, JDBC data sources, JMS/MQ integration, wsadmin scripting (Jython), systemd services, SELinux contexts, and firewalld rules. Part of the ibm-* skill family. family: ibm disambiguation: WebSphere Application Server — profiles, deployment, Liberty, JVM tuning. Message queuing is ibm-mq, a separate product.

IBM WebSphere Application Server — RHEL 9 Administration & Development

Companion skill to rhel-server-admin and db2-rhel. For related workloads see: rhel-web-servers, rhel-docker-host, rhel-monitoring.

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Reference Files

Detailed code examples, patterns, and configuration are in the reference files below. Read the relevant file when working on that area.

File	Covers
install-profiles-deploy.md	WAS architecture, RHEL 9 installation, profile management, and application deployment (WAR/EAR)
security-jvm-clustering-jdbc.md	security configuration, JVM tuning, clustering/HA, JDBC data sources, and JMS/MQ integration
wsadmin-liberty-rhel.md	wsadmin scripting (Jython), WebSphere Liberty/Open Liberty configuration, and RHEL-specific setup

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Anti-Patterns

Anti-Pattern	Why It Fails	Correct Approach
Running WAS traditional when Liberty would suffice	WAS traditional has massive memory footprint, slow startup, complex administration for simple apps	Use Liberty/Open Liberty for new applications; reserve WAS traditional for legacy apps that require it
Deploying application changes without restarting in correct order	WAS caches classloaders, JNDI, and datasource connections; stale state causes intermittent failures	Follow the stop-deploy-start sequence; use rolling restarts in clustered environments
Configuring JDBC datasources without connection pool tuning	Default pool sizes cause connection exhaustion under load; applications block waiting for connections	Set minPoolSize, maxPoolSize, connectionTimeout, and reapTime based on load testing; monitor pool usage
Storing application configuration in server.xml without overrides	Environment-specific config (DB URLs, credentials) hardcoded; requires different builds per environment	Use variable substitution, jvm.options, or bootstrap.properties for environment-specific values
Not configuring JVM heap and garbage collection	Default JVM settings (-Xmx512m) are inadequate for production; GC pauses cause request timeouts	Set -Xms/-Xmx to 60-80% of container memory; use verbose:gc logging; tune GC policy for workload

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Related Skills

Workload	Skill
Core RHEL admin (dnf, SELinux, firewalld, LVM)	rhel-server-admin
Web servers (Nginx, Apache/IHS, Caddy)	rhel-web-servers
Databases (PostgreSQL, MySQL, Redis)	rhel-databases
DB2 LUW on RHEL	db2-rhel
DB2 on z/OS	db2-mainframe
IBM Mainframe (JCL, TSO, ISPF)	ibm-mainframe
Cognos Analytics administration	cognos-admin
Docker / Podman containers	rhel-docker-host
Monitoring (Prometheus, Grafana, PCP)	rhel-monitoring