It may run as a virtual machine, attach to a virtual switch or hypervisor, or be implemented by a virtualization platform to inspect traffic entering, leaving, or moving among virtual workloads.
Placement determines which paths the firewall can observe. Traffic between virtual machines on one host may never cross a physical firewall, while traffic routed through a virtual appliance may require deliberate service insertion. Policy should follow workload identity and approved communication needs when workloads migrate, scale, or receive new addresses.
Key points
Deployment modelsA virtual appliance can protect a subnet or gateway path, while hypervisor- or switch-integrated enforcement can apply rules closer to individual virtual interfaces.
OperationsControl images, software updates, policy templates, administrative interfaces, logs, and lifecycle automation with the same rigor as physical firewalls.
Capacity and resilienceValidate throughput, connection state, inspection cost, failover, and the effect of host or control-plane failure; software deployment does not remove resource limits.
Important limitation“Virtual” describes implementation, not inspection quality or isolation strength. A bypass path, compromised virtualization layer, misplaced instance, or inconsistent policy can leave workload traffic unprotected.