After installation Hyper-V role on the Windows Server it reboots cycling.

If you face the issue - after installation Hyper-V role on the Windows Server it reboots cycling, you need to try advice below.

I faced with it on server HP DL380p Gen 8 with OS Windows Server 2019.

How to increase disk size in Zimbra on virtual machine

If you face the issue with free space on our disk in Zimbra and decide to increase the size, I propose you to consider two scenarios: 

First - You have less than 4 partitions in your virtual disk, like below and you need to extend the disk.

Disk /dev/sda:

   Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *        2048     2099199     1048576   83  Linux

/dev/sda2         2099200   419430399   208665600   8e  Linux LVM

/dev/sda3       419430400   629145599   104857600   8e  Linux LVM

Second - You have 4 partitions in your virtual disk,

Disk /dev/sda:  

   Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *        2048     2099199     1048576   83  Linux

/dev/sda2         2099200   419430399   208665600   8e  Linux LVM

/dev/sda3       419430400   629145599   104857600   8e  Linux LVM

/dev/sda4       629145600   671088639    20971520   8e  Linux LVM