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Shihab Azimullah's avatar
Shihab Azimullah
Copper Contributor
Nov 05, 2019

Direct Routing SBC failover planning in carrier hosted setup (derived trunk model)

Hi,

 

I am trying to setup Teams Direct Routing in our network using the hosted carrier model using two SBCs which are in active/active setup for outbound and inbound calls. I haven't begun any configuration on the O365 part but have completed the SBC side config.


Originally I was planning on using the following using an example base carrier domain sbc.operator.com.
Using the following FQDNS to register an example customer A in a customer tenant on 2 SBCs.
customerA-SBC1.sbc.operator.com
customerA-SBC2.sbc.operator.com

A trunk will be registered in the customerA tenant to connect to customerA-SBC1.sbc.operator.com (sbc 1)
A trunk will be registered in the customerA tenant to connect to customerA-SBC2.sbc.operator.com (sbc 2)

and repeated for every customer. I have already purchased a wildcard cert *.sbc.operator.com

 

However, reading https://docs.microsoft.com/en-us/MicrosoftTeams/direct-routing-sbc-multiple-tenants this week, I see there is a new architecture where SIP trunks are only registered to the carrier tenant and not the customer tenants (as before), which makes sense since only two trunks need be created in total. Trunks in customer tenants do not need to be created and are simply derived from the two carrier trunk associations in the voice routing policy.


I am trying to work out how I can accomplish this.

Do I now need two base domains,etc ?

i.e sbc1.operator.com and sbc2..operator.com

wild certs:
*.sbc1.operator.com
*.sbc2.operator.com

carrier tenant will be registered to sbc1.operator.com sip trunk for sbc 1
carrier tenant will be registered to sbc2.operator.com sip trunk for sbc 2

and 

FQDNs for customerA will be :

customerA.sbc1.operator.com
customerA.sbc2.operator.com

Thanks

 

  • Shihab Azimullah 

     

    For hosting provider failover routing, the hosting provider will need to configure multiple PSTN gateways in their tenant. For example: 

    • sbc1.contoso.com
    • sbc2.contoso.com

    This will require multiple wildcard san names to support each namespace. For example:

    • *.sbc1.contoso.com
    • *.sbc2.contoso.com

    Each customer will be provide two FQDN's to be added to Tenant domain and a single user licensed for SfB Online in the namespace to create the domain in the service forest. For example:

    • cust1.sbc1.contoso.com
    • cust2.sbc1.contoso.com

    Then a route will be created for each of these gateways. 

  • Shihab Azimullah 

     

    For hosting provider failover routing, the hosting provider will need to configure multiple PSTN gateways in their tenant. For example: 

    • sbc1.contoso.com
    • sbc2.contoso.com

    This will require multiple wildcard san names to support each namespace. For example:

    • *.sbc1.contoso.com
    • *.sbc2.contoso.com

    Each customer will be provide two FQDN's to be added to Tenant domain and a single user licensed for SfB Online in the namespace to create the domain in the service forest. For example:

    • cust1.sbc1.contoso.com
    • cust2.sbc1.contoso.com

    Then a route will be created for each of these gateways. 

    • VoipGuyUK's avatar
      VoipGuyUK
      Copper Contributor
      The failover section does not cover it full I think and is missing things. 



      The doc shows base domain of:

      customers.adatum.biz



      Yet for failover the domain has swapped to that of the customer:

      customer1.sbc1.contoso.com
      customer1.sbc2.contoso.com



      The is no explanation of what is going on. Does the carrier domain stay the same, it would suggest not by that example? Do you need 2x carrier domains as sbc1.contoso.com & sbc2.contoso.com or a single contoso.com. Why is it now the customers domain, are derived trunks not used for failover and its back to the old method?
    • teo221935's avatar
      teo221935
      Copper Contributor

      Carolyn Blanding (MS TEAMS) 

       

      Hi We are also trying to setup Teams with Direct routing for the first time using the derived trunk model. so far we have a carrier trunk  which I will call customers.company.com. Following the advice on the link  but we are stuck on this bullet point

       

      In the customer tenant, the carrier need only to add the derived trunk FQDN to the voice routing policies of the users. There is no need to run New-CSOnlinePSTNGateway for a trunk.

       

      To try and follow this We have done the following but the pstn calls are not working

       

      1) Created a subdomain on the customer tenant called cust1.customer.company.com

      2) Activated the subdomain as explained on the document link above

      3) Created a DNS entry for cust1.customer.company.com to point to the public ip of the SBC

      4) on the customer tenant using the teams admin GUI we added an SBC called cust1.customer.company.com then we created a voice route and associated  fqdn cust1.customer.company.com

      5) Enabled user on the customer tenant

       

      Are we missing  a step at this point? Any help would be greatly appreciated

       

       

       

       

      • teo221935 

         

        Sorry for delayed response here and hope you have resolved this. If not, please respond and let me know. 

         

        Summary steps for carrier model. 

        • Carrier creates PSTN Online gateway in their tenant with namespace of sbc1.contoso.com. For failover they would also create a 2nd one, e.g. sbc2.contoso.com
        • Carrier will create wildcard certificate with SAN names for each namespace, e.g. *.sbc1.contoso.com, *.sbc2.contoso.com
        • Carrier will create DNS records resolving to each of the gateway names
        • Carrier will provide customers with unique FQDNs, e.g. cust1.sbc1.contoso.com, cust1.sbc2.contoso.com
        • Customer adds FQDN name as tenant domain name and licenses one user for SfB Online Plan 2 in this domain namespace; e.g. user@cust1.sbc1.contoso.com, user@cust1.sbc2.contoso.com
        • Once domain namespace has been added to tenant service forest, customer adds route specifying SBC FQDN. If provided two FQDN's they will create two routes. 
  • sadwinuser's avatar
    sadwinuser
    Copper Contributor

    I would also like to know this. How is it possible that this is still unanswered 6 months later

    • Pradeep600's avatar
      Pradeep600
      Copper Contributor

      sadwinuser  Failover is configured at SBC level and not in Teams, What you need to do is point the redundant SBC's at Teams Direct Routing with correspondent FQDN's 

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