All application servers showing "Redis Command Timeout" at the same time

Issue

All JBoss Application Servers in the cluster experienced Redis Command Timeout errors at the same time. The SOSReport did not show any abnormalities in CPU or memory usage, suggesting that the issue was likely related to Redis connectivity or configuration.

ERROR [io.undertow.request] (default task-15954) UT005023: Exception handling request to /fivu/sse-listening: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.dao.QueryTimeoutException: Redis command timed out;
nested exception is io.lettuce.core.RedisCommandTimeoutException: Command timed out after 6 second(s)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014)
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:686)
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:791)
        at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:74)
......  
Caused by: org.springframework.dao.QueryTimeoutException: Redis command timed out; nested exception is io.lettuce.core.RedisCommandTimeoutException: Command timed out after 6 second(s)
......  
Caused by: io.lettuce.core.RedisCommandTimeoutException: Command timed out after 6 second(s)
        at io.lettuce.core.ExceptionFactory.createTimeoutException(ExceptionFactory.java:51)