I’m currently using PMM1.
I want to upgrade PMM1 to PMM2 with preserving data.
How do I upgrade from PMM1 to PMM2?
PMM 2 is designed to be used as a new installation — please don’t try to upgrade your existing PMM 1 environment.
You need to re-install and configure PMM.
Release notes: https://www.percona.com/doc/percona-monitoring-and-management/2.x/release-notes/2.0.1.html
I think that it isnt possible:
To use PMM2 you will need to remove any earlier versions of PMM Server and Client as there is no in-place upgrade path for historical data, and then download and run our latest software.
Also here is the instruction of how-to use both clients on the same host.