Comment 0 for bug 2051912

After upgrading neutron from Wallaby to Xena(not ovn), the customer's neutron-l3-agent can't be restarted because of below error [1]

This is because vrrp_pcount = linux_utils.get_process_count_by_name("keepalived")
https://github.com/openstack/neutron/blob/16.4.1/neutron/agent/linux/utils.py#L205

We may put entry to apparmor profile for /proc

but I also find below commit

https://opendev.org/openstack/neutron/commit/f430cd00725f8303f5313cb7784c9aed4b982e62

which is not included in Xena, it is removing code using get_process_count_by_name()

Also, if we backport it. it could be fixed as well.

Could you please give any advice for this issue?

Thanks a lot.

[1]
ERROR neutron Traceback (most recent call last):
ERROR neutron File "/usr/bin/neutron-l3-agent", line 10, in <module>
ERROR neutron sys.exit(main())
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/cmd/eventlet/agents/l3.py", line 24, in main
ERROR neutron l3_agent.main()
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/agent/l3_agent.py", line 52, in main
ERROR neutron server = neutron_service.Service.create(
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/service.py", line 416, in create
ERROR neutron service_obj = cls(host, binary, topic, manager,
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/service.py", line 351, in __init__
ERROR neutron self.manager = manager_class(host=host, *args, **kwargs)
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/agent/l3/agent.py", line 1006, in __init__
ERROR neutron super(L3NATAgentWithStateReport, self).__init__(host=host, conf=conf)
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/agent/l3/agent.py", line 348, in __init__
ERROR neutron self._check_ha_router_process_status()
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/agent/l3/agent.py", line 374, in _check_ha_router_process_status
ERROR neutron vrrp_pcount = linux_utils.get_process_count_by_name("keepalived")
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/agent/linux/utils.py", line 198, in get_process_count_by_name
ERROR neutron return len([p for p in psutil.process_iter(['name']) if
ERROR neutron File "/usr/lib/python3/dist-packages/neutron/agent/linux/utils.py", line 198, in <listcomp>
ERROR neutron return len([p for p in psutil.process_iter(['name']) if
ERROR neutron File "/usr/lib/python3/dist-packages/psutil/__init__.py", line 1432, in process_iter
ERROR neutron a = set(pids())
ERROR neutron File "/usr/lib/python3/dist-packages/psutil/__init__.py", line 1372, in pids
ERROR neutron ret = sorted(_psplatform.pids())
ERROR neutron File "/usr/lib/python3/dist-packages/psutil/_pslinux.py", line 1597, in pids
ERROR neutron return [int(x) for x in os.listdir(b(get_procfs_path())) if x.isdigit()]
ERROR neutron PermissionError: [Errno 13] Permission denied: b'/proc'