Hello there,

we just updated oVirt engine to 4.5.3.2-1.el8 which was smooth, but then when we start to update all nodes, after restart mom-vdsm service is failing to start

mom-vdsm

rpm -q vdsm  
vdsm-4.50.3.4-1.el8.x86_64 (VDSM was updated from
4.50.2.2-1.el8 )

rpm -q mom
mom-0.6.3-1.el8.noarch  (MOM was not updated duting tha last update)

here is error from  /var/log/vdsm/mom.log

2022-10-28 13:17:18,105 - mom - INFO - MOM starting
2022-10-28 13:17:18,138 - mom.HostMonitor - INFO - Host Monitor starting
2022-10-28 13:17:18,138 - mom - INFO - hypervisor interface vdsmjsonrpcclient
2022-10-28 13:17:18,179 - mom.HostMonitor - INFO - HostMonitor is ready
2022-10-28 13:17:18,242 - mom.GuestManager - INFO - Guest Manager starting: multi-thread
2022-10-28 13:17:18,247 - mom.Policy - INFO - Loaded policy '00-defines'
2022-10-28 13:17:18,247 - mom - ERROR - Failed to initialize MOM threads
Traceback (most recent call last):
 File "/usr/lib/python3.6/site-packages/mom/__init__.py", line 35, in run
   host_monitor, guest_manager)
 File "/usr/lib/python3.6/site-packages/mom/PolicyEngine.py", line 42, in __init__
   self.load_policy()
 File "/usr/lib/python3.6/site-packages/mom/PolicyEngine.py", line 71, in load_policy
   read_policy(fname, name.split('.policy')[0])
 File "/usr/lib/python3.6/site-packages/mom/PolicyEngine.py", line 53, in read_policy
   return self.policy.set_policy(policy_name, policyStr)
 File "/usr/lib/python3.6/site-packages/mom/Policy/Policy.py", line 64, in set_policy
   self.code = get_code(Evaluator(), self._cat_policies())
 File "/usr/lib/python3.6/site-packages/mom/Policy/Parser.py", line 543, in get_code
   tokens = scanner.tokenize(string)
 File "/usr/lib/python3.6/site-packages/mom/Policy/Parser.py", line 72, in tokenize
   GenericScanner.tokenize(self, input)
 File "/usr/lib/python3.6/site-packages/mom/Policy/spark.py", line 78, in tokenize
   add_lines = self.index2func[i](groups[i], line)
TypeError: t_default() takes 2 positional arguments but 3 were given


any tip what could be the reason ?

Thaak you

Jirka