You will want to have a look at this whole section of the CUCM
8.6 SRND guide
There are defined maximum supported quantities of endpoints for a given server, as shown in Table 29-5. Note that these values are guidelines only, and it is possible that the system may not be able to support these maximum amounts because of other applications running in the deployment.
Table 29-5 Maximum Number of Endpoints Per Server Platform or OVA Template
Server Platform Characteristics
Maximum Endpoints per Server or OVA Template
Cisco MCS 7845-I3 or OVA equivalent
Cisco MCS 7845 (All other supported models) or OVA equivalent
Cisco MCS 7835 (All supported models) or OVA equivalent
Cisco MCS 7825 (All supported models) or OVA equivalent
Cisco MCS 7816 (All supported models)
Cisco MCS 7815 (All supported models)
The designation of High Availability in Table 29-5 indicates whether those servers may be paired for high availability within a cluster consisting of those servers.
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