In domain mode, stop-server command on server-group fails

My setup:
domain controller + host controller
server group main-server-group, with one server

server is running

when from the CLI I issue the command:
/server-group=main-server-group:stop-servers

the command fails with error message:
{
"outcome" => "failed",
"failure-description" =>

{"domain-failure-description" => "JBAS014749: Operation handler failed: null"}

,
"rolled-back" => true
}