Here is the configuration relation diagram in SNMPv3.A user can be added to a group or not as you need.Once a user joined a group,one or more kinds of views (notfiy-view, write-view, read-view) must be configured.Besides, configurations on user change with the security-level of the group as below 3 diagrams. Note notify-view,write-view and read-view are optional but you have to choose at least one view.In the below diagram,view1,view2,view3 can be the same or different.
Configuring Basic Information
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