In my setup I have Cisco3845 CME routers(C3845-VSEC-CCME/K9), one with CUE module, other with non-CUE(The customer is o.k. not to have voicemails if the CUE-module CME router fails). Both the CME are on same localtion/Lan.
Each router will have one E1 line from PSTN.The Telco sends call to both CMEs in round robin.
How can we achieve CME redundancy in this setup?
1)configuring Redundant Router: Reference CME Admin Guide-Page 117
>>For CME Admin guide, it says on page 144 For configuration information, see the "SCCP: Configuring a Redundant Router" section on page 117.
But under the section:SCCP: Configuring a Redundant Router as a pre requisite it mentions following:
The physical configuration of the secondary router must be as described in the "Redundant Cisco Unified CME Router" section on page 104. >> which means fxo port with Splitter:
2)HSRP>> I heard some issues with phone registration to standby router if active router fails. Also what would happen to incoming calls coming from PSTN>> will they be able to go to IP Phones, since this router is in Standby mode?
Bearing in mind that the Telco is sending calls to both CMEs in round robin, since each CME has one E1 line from Telco.
The only reason to run MGCP or SCCP on an FXS port is to have increased line-side features (hold, conference, park, etc) or ease of management (usually with CUCM).
In the case of a fax machine, you will never use the advanced features, and with CME SCCP FXS ports are harder to manage. For a CME system, you're correct and should just use normal Router controlled FXS ports instead of SCCP.
This is an example of a working fax configuration:
dial-peer voice 1 pots
(outgoing pots dial peer)
dial-peer voice 2 pots
(fxs port with fax machine)