Description of problem: On a three node cluster with 2000 volumes and continuos IO on 6 volumes. Performing in-service upgrade from 6.0.7 to 6.0.11 build . First node upgraded successfully and heal is completed. Upgraded second node and performed node reboot. After reboot one brick is offline. Version-Release number of selected component (if applicable): glusterfs-6.0-11.el7rhgs.x86_64 How reproducible: 1/1 Steps to Reproduce: 1. On three node cluster with brick mux enabled, Created 2000 volumes(replica 3) and are in started state. 2. Mounted 6 volumes and continuous IO is being done on those volumes. 3. Perfromed in-service upgrade to latest build. 4. First node upgrade is successful and all processes are online and heal completed successfully 5. Second node upgraded successfully and performed node reboot after upgrade. Actual results: One brick process is offline. Expected results: All brick process should be online after node reboot. Additional info: