Here's the full error:
TASK [create vms] ***************************************************************************************************
failed: [localhost] (item={'value': {u'node': u'ceph-hv-01', u'memory_size': u'12288', u'template': u'centos7-template', u'cores': u'4', u'ipconfig': u'{"ipconfig0":"ip=172.30.20.191/24,gw=172.30.20.1"}', u'net': u'{"net0":"virtio,bridge=vmbr320"}', u'cloudinit': True}, 'key': u'stu-test-10'}) => {"ansible_loop_var": "item", "changed": false, "item": {"key": "stu-test-10", "value": {"cloudinit": true, "cores": "4", "ipconfig": "{\"ipconfig0\":\"ip=172.30.20.191/24,gw=172.30.20.1\"}", "memory_size": "12288", "net": "{\"net0\":\"virtio,bridge=vmbr320\"}", "node": "ceph-hv-01", "template": "centos7-template"}}, "msg": "creation of qemu VM stu-test-10 with vmid 102 failed with exception=500 Internal Server Error: {\"data\":null}"}
