The "Backup" that is available via the web interface (Maintenance > Backup and Restore > Take backup) will just make a backup of the config files (essentially a dump of the output of the xconfiguration of the endpoint). It will not save any local phonebook entries, or log files.
If you want to keep the log files, I suggest you download a logs archive separately. I can't recall the exact steps to do this on the old TC7.2.1, but it's possible on newer versions (ie TC7.3.21 which is the latest available) via Diagnostics > Log Files > Download logs archive.
The Local Contacts can also be exported similarly from the web interface as an XML file which you can then re-import later. Configuration > Local Contacts Management > Export. (And then use the Import option to get it back in again afterwards).
Please also note: The EX60 reached its End-of-Support date on 30 June 2020, so it would be highly recommended that you consider replacing it with a newer and supportable model (such as one of the Webex Desk Series endpoints).
Wayne
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