Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations John Tel on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Mitel MBG - understanding RTP settings 1

augiedawg6123

Systems Engineer
Apr 8, 2025
10
Is it possible to have a single IP address on an MBG, and still get two-way RTP traffic in the following scenarios:

1. Phones registered to MiVB can communicate to phones registered on MBG (locally, not teleworker)
2. Phones registered to MiVB can communicate to phones registered on MBG (externally, teleworker)
3. Phones registered locally to MBG can communicate with phones registered locally to MBG
4. Phones registered locally to MBG can communicate with phones registered externally to MBG

The network profile settings mystify me because it seems like it's impossible to obtain the above. I have a "custom configuration" where ICP side is private IP of MBG, set side is public IP which is NAT'd to the MBG.

If a phone is registered to MBG, doesn't matter if it's internally or externally, it will always send RTP traffic to public IP I have configured. This obviously won't work when the phone is internal. Is it just impossible to have RTP work in any scenario if you have phones registered to MiVB, MBG (some teleworker, some not)??
 
Would be nice if anyone could confirm, but I think I found my answer in MBG Engineering Guidelines. It is not possible to record both LAN and Teleworker sets on a single MBG server. You would need an additional MBG server handling the teleworker sets. I'm sure that's because of this rigid RTP setting where all you get to configure is ICP side and set side RTP.
 
If you have a single IP (LAN), then your MBG config will be that of a DMZ deployment. You will need to be very specific with your NATing rules, Mitel has documented this clearly in the Engineering guidelines.

Yes it is possible for the 4 scenarios you have outlined.
 
Thanks for the reply.

The only way I see this working without spinning up another MBG server would be to configure NAT reflection or NAT hairpining that basically tells the firewall when it receives traffic from the LAN side destined for its public IP, to send it back in using the same destination NAT rules configured to get traffic to private IP of MBG as if it were coming from the public internet. That seems crazy considering there should be an option in Mitel to get it to go to the correct place to begin with.
 
if you have internally connected devices then they can only be src tapped by a MBG that doesnt have a public ip as the set side streaming address

MOST MBG TW require that to be set to allow the publically connected devices to be recorded

we have used mbg sip proxies with 3rd nic for SIp trunk as the SRC server for internally connected devices
and leaving the MBGTW as the SRc for publically connected devices
 
Heya Billz66, can you elaborate on the

"we have used mbg sip proxies with 3rd nic for SIp trunk as the SRC server for internally connected devices and leaving the MBGTW as the SRc for publically connected devices"
 
on MBG you can have 3 NICS
eth0 - lan - connected to internal voice network
eth1 - wan - if used for teleworker MUST be a direct connected public ip
eth2 - additional lan - can be used to connect to a carrier cross connect or NTU for SIP trunk

if the MBG has a public IP on its wan - it cant then be used for internal SRC connections ( call recording)

if the MBG has lan and a trunk connected via eth 2 ( 3rd nic) rthen it can be used as internal SRC

pretty sure we have also used the MBG on a Micollab as internal SRC ( as long as it doesnt have eth1 connected to public internet)
 
Really appreciate the info! This makes sense. Up and coming MiVB installer so on information overload.
 

Part and Inventory Search

Sponsor

Back
Top