Cisco Cisco Expressway
Appendix 3: Connecting Expressway to a Cluster of Unified CM Nodes
When connecting Expressway to a cluster of Unified CM nodes, Expressway needs to be able to route calls to each
Unified CM node.
Unified CM node.
This can be done in 2 ways, in order of preference:
1.
With a single neighbor zone in Expressway with the Unified CM nodes listed as location peer addresses.
2.
By using DNS SRV records and an Expressway DNS zone.
Note that both options ensure that the Expressway to Unified CM call load is shared across Unified CM nodes.
Option 1: Using a Single Neighbor Zone
Unified CM Configuration
When in a cluster, Unified CM needs to accept calls routed to number@domain (instead of number@<ip address of
Unified CM>) so that Expressway can send the call to any Unified CM node without having to make sure that the
domain portion matches the IP address of the node that the call is being sent to.
Unified CM>) so that Expressway can send the call to any Unified CM node without having to make sure that the
domain portion matches the IP address of the node that the call is being sent to.
Ensure that the Cluster Fully Qualified Domain Name (System > Enterprise parameters, in the Clusterwide Domain
Configuration section) is set to the same domain as the video network, for example exp.domain.
Configuration section) is set to the same domain as the video network, for example exp.domain.
Expressway-C Configuration
The Expressway configuration requires an update to the neighbor zone:
1.
Go to Configuration > Zones.
2.
Select the Unified CM neighbor zone.
3.
Configure the fields as follows:
Peer 1 address
IP address of Unified CM node 1, or the domain of Unified CM node 1.
Peer 2 address
IP address or the domain of Unified CM node 2.
Peer 3 address
IP address or the domain of Unified CM node 3, or blank if no Unified CM node 3.
.... up to Peer 6
address
... repeat up to the IP address or the domain of Unified CM node 6, or leaving it blank if
there is no Unified CM node.
there is no Unified CM node.
Option 2: Using a DNS Zone
Unified CM Configuration
Ensure that the Cluster Fully Qualified Domain Name (System > Enterprise parameters, in the Clusterwide Domain
Configuration section) is set to the same domain as the video network, for example exp.domain.
Configuration section) is set to the same domain as the video network, for example exp.domain.
DNS Server Configuration
Configure the DNS server (that is used by the Expressway) with DNS SRV records for the Unified CM cluster.
■
_sips._tcp.fqdn_of_cucm_clusterrecords for TLS connectivity (one record for each Unified CM node); or
■
_sip._tcp.fqdn_of_cucm_clusterrecords for TCP connectivity (one record for each Unified CM node)
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Cisco Expressway SIP Trunk to Unified CM Deployment Guide
Appendix 3: Connecting Expressway to a Cluster of Unified CM Nodes