Good day Stevenchow,
There is a good collection of Juniper MIBs you can compile into a custom SNMP database for your ipMonitor installation here:
If you have any additional questions regarding this, please do not hesitate to ask.
Chris Foley - SolarWinds - Support Specialist
Support: 866.530.8040 | Fax: 512.857.0125
network management simplified | solarwinds.com