Hi, @Sergi Díaz Ruiz
Thank you for posting in Microsoft Q&A forum and thank you for the update.
The SMSMP switch is not mandatory, but it is recommended to use it when installing the Configuration Manager client with client.msi properties. The SMSMP property specifies the initial management point for the client and removes the dependency on service location solutions such as Active Directory Domain Services and DNS.
It is also recommended to use the FSP property and install a fallback status point to better monitor client installation and assignment, and identify any communication problems.
For more information about these options, see the "Recommendations for client deployment in Configuration Manager" article.
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