You need to login to the egosh first ( for example: egosh user logon -u Admin -x Password123)
then run egosh service list -l
This will give you a listing of all the services ego is controlling. You should see something like "ObjectSpawner" if you've configured it as a restart-able service.
Here's the syntax for all the egosh commands:
https://www.ibm.com/support/knowledgecenter/en/SSGSMK_6.1.1/reference_sym/egosh.1.html
You can then use the following to manage the service:
egosh service [start|stop] <ServiceName>