Could be someone please help me find the Quickspecs Specifications Sheet for Logger gen9 specific for the model L7600?
The documentation should be corrected shortly.
As a general rule - upgrade process is more or less, upgrade of OS as per support matrix / apply logger upgrade.
Typically, upgrade can be performed on previous Version, so for logger 7 specifically:
OS should be upgrade to either RHEL (CentOS) 7.7 / 6.10
And Logger upgrade can be applied to either Logger 6.70 / 6.71
For a logger appliance, and additional pre-req file is required as mentioned in my note above. Please let me know if you have any further questions on this.