We are experiencing an issue on several Rocky Linux 9 servers after OS patching and reboot.
Environment:
- OS: Rocky Linux 9
- Application server: JBoss
- Component: mod_cluster
- Environment: Production
After patching and rebooting the Rocky Linux servers, JBoss started reporting mod_cluster communication errors with the Apache/mod_cluster nodes.
Examples:
MODCLUSTER000043: Failed to send STATUS to Apache/mod_cluster
MODCLUSTER000042: Error MEM sending STATUS command,
configuration will be reset:
MEM: Can’t read node with JVMRoute
The issue appeared after the OS patching/reboot, although at this point we cannot confirm that the Rocky Linux updates are the root cause.
We are currently checking:
- Network connectivity between JBoss and Apache/mod_cluster
- Firewall status
- SELinux status
- Kernel changes
- Packages updated during the maintenance
- JBoss/mod_cluster node registration
Could any Rocky Linux 9 update potentially affect mod_cluster communication, networking, firewall, SELinux, OpenSSL or related components?
Which OS-level logs or package changes would you recommend checking to determine whether the issue is related to the Rocky Linux patching?
Thank you.