On the OceanStor 5600 V3, the upper layer runs the redhat KVM virtualization and the VMware virtualization. In the fourth month, the storage virtual disk is stuck three consecutive times and the virtual machine is also stuck. The root cause is because of a Redhat software bug, while the solution is to upgrade the storage version, adjusting the multipath configuration.
1.Check the log about the vm business hang.
By analyzing the RedHat host log it is found that the host has an IO response stuck in 2018-01-27 12:51.
2. 20:51:41. The host multipath reported a path interruption (checked that each host had only one path). The available path of the system became 0. Because the host did not have a path, the KVM virtualization service was interrupted.
3.The KVM VM is stuck because Redhat has a known bug (KVM will hang automatically after the back-end storage is restarted and cannot be automatically restored). The KVM version needs to be upgraded and the multipathing solution must be adjusted.
