You can create a least privileged user named LPU for Arista EOS by running the following command in the Arista EOS CLI. Note that the management pack requires a least privileged user with the operator role, the default role given to a user by Arista EOS.
switch(config) #username LPU secret PASSWORD
switch(config) #username LPU role network-admin
For more information, see Arista's EOS documentation