【参考】以下と同様のことをデータソースで実行しています。

検証環境

前提

Testing database connections in Open Liberty apps with REST APIs - OpenLiberty.ioに記載の設定をします。
この環境ではfeatureManagerに以下を追加します。

$ vi /opt/ibm/wlp/usr/servers/defaultServer/server.xml

  <featureManager>
    <feature>appSecurity-2.0</feature>
    <feature>restConnector-2.0</feature>
  </featureManager>

実行結果

% curl --insecure -u wsadmin:passw0rd "https://<hostname>:9443/ibm/api/validation/dataSource/PdprofDataSource" |jq
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   391  100   391    0     0    378      0  0:00:01  0:00:01 --:--:--   378
{
  "uid": "PdprofDataSource",
  "id": "PdprofDataSource",
  "jndiName": "jdbc/derbyEmbedded",
  "successful": true,
  "info": {
    "databaseProductName": "DB2/LINUXX8664",
    "databaseProductVersion": "SQL110580",
    "jdbcDriverName": "IBM Data Server Driver for JDBC and SQLJ",
    "jdbcDriverVersion": "4.32.28",
    "schema": "DB2INST1",
    "user": "db2inst1"
  }
}

server.xmlで、dataSourceのdb2jcc.propertiesから認証の設定を削除して、authDataを使用するように変更した場合

  <dataSource id="PdprofDataSource" jdbcDriverRef="Db2Driver" jndiName="jdbc/derbyEmbedded" type="javax.sql.DataSource" containerAuthDataRef="DBAuth">
        <connectionManager maxPoolSize="5" minPoolSize="2"/>
        <properties.db2.jcc databaseName="PDPROF"
                      serverName="<hostname> portNumber="50000"
                      autoCommit="FALSE" traceLevel="-1"/>
    </dataSource>
    <authData id="DBAuth" user="db2inst1" password="passw0rd" />

auth=container&authAlias=DBAuth　をつけて実行します

% curl --insecure -u wsadmin:passw0rd "https://<hostname>:9443/ibm/api/validation/dataSource/PdprofDataSource?auth=container&authAlias=DBAuth" |jq
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   391  100   391    0     0    512      0 --:--:-- --:--:-- --:--:--   512
{
  "uid": "PdprofDataSource",
  "id": "PdprofDataSource",
  "jndiName": "jdbc/derbyEmbedded",
  "successful": true,
  "info": {
    "databaseProductName": "DB2/LINUXX8664",
    "databaseProductVersion": "SQL110580",
    "jdbcDriverName": "IBM Data Server Driver for JDBC and SQLJ",
    "jdbcDriverVersion": "4.32.28",
    "schema": "DB2INST1",
    "user": "db2inst1"
  }
}

失敗例。db2jcc.propertiesに誤ったパスワードを設定すると、以下のようになります

% curl --insecure -u wsadmin:passw0rd "https://<hostname>:9443/ibm/api/validation/dataSource/PdprofDataSource" |jq
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  7172  100  7172    0     0   9669      0 --:--:-- --:--:-- --:--:--  9665
{
  "uid": "PdprofDataSource",
  "id": "PdprofDataSource",
  "jndiName": "jdbc/derbyEmbedded",
  "successful": false,
  "failure": {
    "sqlState": "28000",
    "errorCode": "-4214",
    "class": "java.sql.SQLInvalidAuthorizationSpecException",
    "message": "[jcc][t4][2013][11249][4.32.28] Connection authorization failure occurred.  Reason: User ID or Password invalid. ERRORCODE=-4214, SQLSTATE=28000 DSRA0010E: SQL State = 28000, Error Code = -4,214",
    "stack": [
      "com.ibm.db2.jcc.am.b7.a(b7.java:808)",
      "com.ibm.db2.jcc.am.b7.a(b7.java:66)",
      "com.ibm.db2.jcc.am.b7.a(b7.java:133)",
      "com.ibm.db2.jcc.t4.b.f(b.java:2683)",
      "com.ibm.db2.jcc.t4.b.b(b.java:2011)",
      "com.ibm.db2.jcc.t4.z.r(z.java:961)",
      "com.ibm.db2.jcc.t4.z.k(z.java:494)",
      "com.ibm.db2.jcc.t4.z.c(z.java:144)",
      "com.ibm.db2.jcc.t4.b.k(b.java:1520)",
      "com.ibm.db2.jcc.t4.b.b(b.java:1433)",
      "com.ibm.db2.jcc.t4.b.a(b.java:6862)",
      "com.ibm.db2.jcc.t4.b.b(b.java:949)",
      "com.ibm.db2.jcc.t4.b.a(b.java:862)",
      "com.ibm.db2.jcc.t4.b.a(b.java:457)",
      "com.ibm.db2.jcc.t4.b.a(b.java:430)",
      "com.ibm.db2.jcc.t4.b.<init>(b.java:368)",
      "com.ibm.db2.jcc.DB2DataSource.getSimpleConnection(DB2DataSource.java:139)",
      "com.ibm.db2.jcc.DB2DataSource.getConnection(DB2DataSource.java:116)",
      "com.ibm.db2.jcc.DB2DataSource.getConnection(DB2DataSource.java:91)",
      "com.ibm.ws.rsadapter.impl.DatabaseHelper.getConnectionFromDatasource(DatabaseHelper.java:1467)",
      "com.ibm.ws.rsadapter.impl.DB2JCCHelper.getConnectionFromDatasource(DB2JCCHelper.java:638)",
      "com.ibm.ws.rsadapter.impl.WSManagedConnectionFactoryImpl$7.run(WSManagedConnectionFactoryImpl.java:1032)",
      "com.ibm.ws.rsadapter.impl.WSManagedConnectionFactoryImpl$7.run(WSManagedConnectionFactoryImpl.java:1019)",
      "java.base/java.security.AccessController.doPrivileged(AccessController.java:785)",
      "java.base/java.security.AccessController.doPrivilegedWithCombiner(AccessController.java:841)",
      "com.ibm.ws.rsadapter.impl.WSManagedConnectionFactoryImpl.getConnectionUsingDS(WSManagedConnectionFactoryImpl.java:1019)",
      "com.ibm.ws.rsadapter.impl.WSManagedConnectionFactoryImpl.getConnection(WSManagedConnectionFactoryImpl.java:848)",
      "com.ibm.ws.rsadapter.impl.WSManagedConnectionFactoryImpl.createManagedConnection(WSManagedConnectionFactoryImpl.java:698)",
      "com.ibm.ejs.j2c.FreePool.createManagedConnectionWithMCWrapper(FreePool.java:1389)",
      "com.ibm.ejs.j2c.FreePool.createOrWaitForConnection(FreePool.java:1263)",
      "com.ibm.ejs.j2c.PoolManager.reserve(PoolManager.java:1471)",
      "com.ibm.ejs.j2c.ConnectionManager.allocateMCWrapper(ConnectionManager.java:576)",
      "com.ibm.ejs.j2c.ConnectionManager.allocateConnection(ConnectionManager.java:308)",
      "com.ibm.ws.rsadapter.jdbc.WSJdbcDataSource.getConnection(WSJdbcDataSource.java:143)",
      "com.ibm.ws.rsadapter.jdbc.WSJdbcDataSource.getConnection(WSJdbcDataSource.java:117)",
      "com.ibm.ws.rest.handler.validator.jdbc.DataSourceValidator.validate(DataSourceValidator.java:91)",
      "com.ibm.ws.rest.handler.validator.internal.ValidatorRESTHandler.handleSingleInstance(ValidatorRESTHandler.java:283)",
      "com.ibm.wsspi.rest.config.ConfigBasedRESTHandler.handleRequest(ConfigBasedRESTHandler.java:326)",
      "com.ibm.ws.rest.handler.validator.internal.ValidatorRESTHandler.handleRequest(ValidatorRESTHandler.java:483)",
      "com.ibm.ws.rest.handler.internal.service.RESTHandlerContainerImpl.handleRequest(RESTHandlerContainerImpl.java:465)",
      "com.ibm.ws.rest.handler.internal.servlet.RESTProxyServlet.handleWithDelegate(RESTProxyServlet.java:121)",
      "com.ibm.ws.rest.handler.internal.servlet.RESTProxyServlet.service(RESTProxyServlet.java:66)",
      "javax.servlet.http.HttpServlet.service(HttpServlet.java:791)",
      "com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1266)",
      "com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:754)",
      "com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:451)",
      "com.ibm.ws.webcontainer.filter.WebAppFilterChain.invokeTarget(WebAppFilterChain.java:197)",
      "com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:100)",
      "com.ibm.ws.app.manager.wab.internal.OsgiDirectoryProtectionFilter.doFilter(OsgiDirectoryProtectionFilter.java:92)",
      "com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:199)",
      "com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:93)",
      "com.ibm.ws.security.jaspi.JaspiServletFilter.doFilter(JaspiServletFilter.java:58)",
      "com.ibm.ws.webcontainer.filter.FilterInstanceWrapper.doFilter(FilterInstanceWrapper.java:199)",
      "com.ibm.ws.webcontainer.filter.WebAppFilterChain.doFilter(WebAppFilterChain.java:93)",
      "com.ibm.ws.webcontainer.filter.WebAppFilterManager.doFilter(WebAppFilterManager.java:1069)",
      "com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:1260)",
      "com.ibm.ws.webcontainer.filter.WebAppFilterManager.invokeFilters(WebAppFilterManager.java:1078)",
      "com.ibm.ws.webcontainer.servlet.CacheServletWrapper.handleRequest(CacheServletWrapper.java:77)",
      "com.ibm.ws.webcontainer40.servlet.CacheServletWrapper40.handleRequest(CacheServletWrapper40.java:87)",
      "com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:978)",
      "com.ibm.ws.webcontainer.osgi.DynamicVirtualHost$2.run(DynamicVirtualHost.java:293)",
      "com.ibm.ws.http.dispatcher.internal.channel.HttpDispatcherLink$TaskWrapper.run(HttpDispatcherLink.java:1284)",
      "com.ibm.ws.http.dispatcher.internal.channel.HttpDispatcherLink.wrapHandlerAndExecute(HttpDispatcherLink.java:500)",
      "com.ibm.ws.http.dispatcher.internal.channel.HttpDispatcherLink.ready(HttpDispatcherLink.java:459)",
      "com.ibm.ws.http.channel.internal.inbound.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:569)",
      "com.ibm.ws.http.channel.internal.inbound.HttpInboundLink.handleNewRequest(HttpInboundLink.java:503)",
      "com.ibm.ws.http.channel.internal.inbound.HttpInboundLink.processRequest(HttpInboundLink.java:363)",
      "com.ibm.ws.http.channel.internal.inbound.HttpInboundLink.ready(HttpInboundLink.java:330)",
      "com.ibm.ws.http.channel.h2internal.H2StreamProcessor$Http2Ready.run(H2StreamProcessor.java:1849)",
      "com.ibm.ws.threading.internal.ExecutorServiceImpl$RunnableWrapper.run(ExecutorServiceImpl.java:298)",
      "java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)",
      "java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)",
      "java.base/java.lang.Thread.run(Thread.java:835)"
    ]
  }
}