The Logical Router (Distributed Logical Router) is installed on ESXi hosts as a VIB by the NSX manager during host preparation. The installation does not require any interruption to ESXi hosts. Removal of the VIB does require a host restart though. The DLR runs in kernel space and sits on the data plane. A Logical Router is defined as an instance. Each DLR created is an instance and participating hosts receive a copy of the instance.