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Maximum number of CCM user


Does anybody can point me the link or webpage regarding to the maximum of users that I can configure in CCM?

I'd like to follow datasheet like if my server is 7845 then I can have approximately 7500 users. But I'm not quite sure this is a proper estimation.

Thank you very much.



Re: Maximum number of CCM user

DC-Directory supports up to 5 million directory entries on a single server, and a theoretically unlimited number of entries across a multi-server distributed directory.

The recommended number of entries per server will depend on the particular usage scenarios and requirements, and the nature of the data held in the directory.


Community Member

Re: Maximum number of CCM user

Can you please provide clarification on your answer?

So a single call manager will work with an LDAP directory that has 5 million users?

Re: Maximum number of CCM user

Actually, he is talking about DC Directory which was the local x.500 directory option for customers deploying Call Manager 3.x/4.x.  I am not sure about the scalability potential of DC Directory.  I just wanted to clarify that it wasn't (thread was from 2006) that was being discussed.



HTH -Bill (b) (t) @ucguerrilla

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Re: Maximum number of CCM user

The 7,500 figured mentioned for the 7845 refers more to the supported number of phones than users. This is a rough estimation and any large deployment should be planned using the appropriate capacity planning tools.

CUCM uses a server clustering design with the typical maximum number of phones per cluster being 30,000 although Cisco have deployed "mega-clusters" for some customers that exceed this number. Clusters can also be linked together and newer versions of CUCM support cross-cluster extension mobility so the limits are fairly elastic.

The best place to understand CUCM is at the SRND design guide.

I am sure that if you have a requirement for 5 million users your local Cisco office would love to talk to you .

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