New option: require KVM. If false, Qemu VMs will not be prevented to run without KVM.

conf/gns3_server.conf

@@ -63,3 +63,5 @@ license_check = True
 [Qemu]
 ; !! Remember to add the gns3 user to the KVM group, otherwise you will not have read / write permssions to /dev/kvm !!
 enable_kvm = True
+; Require KVM to be installed in order to start VMs
+require_kvm = True

gns3server/compute/qemu/qemu_vm.py

@@ -1624,7 +1624,10 @@ class QemuVM(BaseNode):
                 return False
 
             if not os.path.exists("/dev/kvm"):
-                raise QemuError("KVM acceleration cannot be used (/dev/kvm doesn't exist). You can turn off KVM support in the gns3_server.conf by adding enable_kvm = false to the [Qemu] section.")
+                if self.manager.config.get_section_config("Qemu").getboolean("require_kvm", True):
+                    raise QemuError("KVM acceleration cannot be used (/dev/kvm doesn't exist). You can turn off KVM support in the gns3_server.conf by adding enable_kvm = false to the [Qemu] section.")
+                else:
+                    return False
             return True
         return False
 

scripts/remote-install.sh

@@ -212,6 +212,7 @@ report_errors = True
 
 [Qemu]
 enable_kvm = True
+require_kvm = True
 EOFC
 
 chown -R gns3:gns3 /etc/gns3
@@ -298,6 +299,7 @@ report_errors = True
 
 [Qemu]
 enable_kvm = True
+require_kvm = True
 EOFSERVER
 
 log "Install packages for Open VPN"