Describe the issue:
Restful server started failed when i tried to run the mnist example

Environment:

• NNI version:2.4

• Training service (local|remote|pai|aml|etc):local

• Client OS:ubuntu

• Python version:3.8

• Is conda/virtualenv/venv used?:?

• Is running in Docker?: no

Configuration:

• Experiment config (remember to remove secrets!):

• Search space:
  INFO: Starting restful server...
  ERROR: Restful server start failed!
  INFO: Stdout:

            Experiment start time 2021-08-18 14:46:26

INFO: Stderr:

            Experiment start time 2021-08-18 14:46:26

Failed to create log dir: RangeError: Invalid time value
at Date.toISOString ()
at Logger.log (xx/.local/lib/python3.8/site-packages/nni_node/common/log.js:54:72)
at Logger.error (xx/.local/lib/python3.8/site-packages/nni_node/common/log.js:41:14)
at xx/.local/lib/python3.8/site-packages/nni_node/main.js:109:33

Log message:

• nnimanager.log:
• dispatcher.log:
• nnictl stdout and stderr:

Could anyone help me look at this issue? stuck on this for a week