The ISSO will ensure that only authorized management traffic is forwarded by the multi-layer switch from the production or managed VLANs to the management VLAN.
If the management systems reside within the same Layer 2 switching domain as the managed network elements, then separate VLANs will be deployed to provide separation at that level. In this case, the management network still has its own subnet while at the same time it is defined as a unique VLAN. Inter-VLAN routing or the routing of traffic between nodes residing in different subnets requires a router or multi-layer switch (MLS). Access control lists must be used to enforce the boundaries between the management network and the network being managed. When using a MLS, an alternate method to prevent inter-VLAN routing is to configure the management Virtual Routing and Forwarding (VRF) to not import route targets from other VRFs which would ensure there is no reachability between networks.
If an MLS is used to provide inter-VLAN routing, configure an inbound ACL for the management network VLAN interface.
Review the configuration to determine if an inbound ACL has been configured for the management VLAN interface to block non-management traffic. If an inbound ACL has not been configured, this is a finding.