US Patent 10949125 Virtualized block storage servers in cloud provider substrate extension

A first request to launch a first virtual machine to host a block storage server application is received. At least a portion of a storage capacity of one or more storage devices of a host computer system is provisioned to the first virtual machine as a provisioned storage device. The block storage server application is executed with the first virtual machine. As part of executing the block storage server application, a logical volume is created on the provisioned storage device in response to a second request from a block storage service of a provider network to create the logical volume, a third request to perform an input/output operation is received and performed with the logical volume.