1. View the /var/log/libvirt/libvirtd.log file. The failure cause is found that the balloon operation of the VM times out.
Figure 1 linvirtd log
2. View the /var/log/memoc/memoc.log file. Errors are reported all the time for the balloon operation of the VM.
Figure 2 memoc log
3. The total physical memory of the CNA node is 32 GB. Check the memory of the CNA node. It is found that the memory is insufficient and the VM fails to obtain all the memory, resulting in the balloon operation timeout.
Figure 3 Insufficient memory
In the memory reuse scenario, all the memory needs to be obtained before VM hot migration is started. In this case, the memory of the CNA node is insufficient, causing the hot migration failure.