Multiple IT VLANs-BAS access switches connected to the IT network with access ports - Metasys - LIT-12012458 - Field Device - 13.0

Metasys IP Networks for BACnet/IP Controllers Technical Bulletin

Brand
Metasys
Document type
Technical Bulletin
Document number
LIT-12012458
Version
13.0
Revision date
2023-10-23
Product status
Active
Language
English

As was the case when using a single IT VLAN, both the network engine s and the BAS access switches can be directly connected to the IT network by way of access ports. For the BAS access switch to connect to an access port on an IT access layer switch, the uplink port of the BAS access switch must be configured as a routed port. The network engines, which are in the same subnets as the BAS access switches’ routed port interfaces, must be connected directly to the IT access layer switches rather than to the BAS access switches. This approach requires additional IT switch ports (one for each of the network engine s) and physical drops from the IT closets where the IT access layer switches reside to the mechanical rooms where the network engine s reside, but is less burdensome for the customer’s IT department to configure. Figure 16 illustrates the network configuration of Figure 15 where both the network engine s and BAS access switches are connected to access ports in the IT network.

Figure 1. Multiple IT VLANs-BAS access switches connected to the IT network with access ports

The network engine s and BAS access switches still reside in existing IT VLANs 2 and 3, and the IP controllers still reside in BAS VLANs 10, 11, and 12. The IP addresses and default gateways are also the same as for connecting the BAS access switches to the IT network by way of trunks. The 2 major differences are:

  1. The network engine s are physically connected to the IT access layer switches rather than the BAS access switches.
  2. The IT BAS subnet addresses of the BAS access switches are assigned to the routed ports on the BAS access switches rather than being configured as SVIs on the BAS access switches.