Could we create a second User Profile Service Application ?

Yes you can but ,
If you have only one server in your farm you can use just one User Profile Service Application (UPA) in this server because the windows Service of User Profile Syncronization Service just configurable only one UPA. So if you have more than one sharepoint server in your farm for example 3 server;  you can create more than 3 UPA but you can only syncronize 3 of them.

For Another scenario, i assume that you have only one server and already provisioned one UPA and configured the syncronization connection. After adding second UPA as you know you can not able to add any Sycronization connection for Second UPA . But if you stop CA-> Services On Server -> User Profile Syncronization Service and restart it will prompt you to select UPA options mean you can change the relation for specific UPA . Still only one UPA can able to sync for one server.

Advertisement

Missing Sharepoint Central Administration application

Somehow our friendly Central Administration web application was deleted or collapsed irreversably. Than how could you reprovision it ? sure you can rerun Configuration Wizard but it will take time and makes lots of change. Thanks to Microsoft that we have console executable named psconfig.exe in DRIVE:\Program Files\Common Files\Microsoft Shared\Web Server Extentions\14\BIN\psconfig.exe

To provision CA use that command:

psconfig.exe -cmd adminvs -port 9999 -provision -windowsauthprovider onlyusentlm

Manages the SharePoint Central Administration Web application on the local computer. Takes the following optional parameters:

[-provision]

Provisions the SharePoint Central Administration Web application on this server. Provisioning creates a new SharePoint Central Administration Web application and an application pool running under the server farm administrator’s account.

[-unprovision]

Unprovisions the SharePoint Central Administration Web application from this server. Unprovisioning removes the SharePoint Central Administration Web application and its application pool.

[-port <port number>]

The SharePoint Central Administration Web application port is a global setting to the server farm. When changing the port, a SharePoint Timer service job is dispatched to synchronize the port for all SharePoint Central Administration Web applications in the server farm. If a port is not specified, the port that is used for existing SharePoint Central Administration Web applications in the server farm is used. If a SharePoint Central Administration web Application has not been provisioned in the server farm, the default port selected will be random if a port is not specified.

[-windowsauthprovider <enablekerberos | onlyusentlm>]

The SharePoint Central Administration Web application authentication provider is a global setting to the server farm. When you change the authentication provider, a SharePoint Timer service job will be dispatched to synchronize the provider on all SharePoint Central Administration Web Applications in the server farm. If onlyusentlm is specified, NTLM will be the exclusive authentication provider for all SharePoint Central Administration Web applications. All other authentication providers are disabled and NTLM will be the only authentication provider allowed. If enablekerberos is specified, Kerberos authentication is enabled for all SharePoint Central Administration Web applications. If an authentication provider is not specified, the provider that is used for existing SharePoint Central Administration Web applications in the server farm will be used. If a SharePoint Central Administration Web application has not been provisioned in the server farm, the Kerberos authentication provider will be enabled if an authentication provider is not specified.

More Info:
Psconfig command-line reference (SharePoint Server 2010)
http://technet.microsoft.com/en-us/library/cc263093.aspx