2x Cisco SG300 + Tagged VLAN + No VLAN on Pfsense setup + manually added route on Server

[elemy]

Hello,

i have a question what would be the best approach for my current setup.

We got a Cisco CPE (BGP protocol) from our telephony provider which has a DSL modem and a few LAN ports.

The purpose of this thing is to provide us with a backup phone line (SIP) if our internet goes down.

Right now our switches are stuffed so i have the PBX on a virtual server with a tagged VLAN, that switch is connected to another switch, also tagged, the CPE is then connected on the second switch with a tagged VLAN and with an untagged port for network connectivity.

The CPE has a direct connection to the providers phone network, primarly routing over our internet and if that goes down it switches over to the modem for the backup line.

           ________________ pfSense _____________ internet
  LAN | 
           ----untagged------- CPE -----tagged------ PBX
                                            |
                                      Modem

I only tagged the ports on the switches and pfsense doesn't know about the VLAN at all i also added a route on our PBX to route traffic through the CPE.

If i ping the PBX/CPE from pfSense ping times are bad, but that would be logical (imho) as pfSense sends the ping out to WAN.
If i ping from the PBX to CPE i get 0.6 ms, can't try the other way around as i have no access to the CPE.

It is all working so far, but is this the right approach? Or do you guys say i could do better :)

cheers

elemy