no neutron-plugin services checks

[JuanJo Ciarlante]

nova-compute nrpe hooks currently adds these service checks:

# grep ^c /etc/nagios/nrpe.d/check_{nova-compute,libvirt-bin}.cfg
/etc/nagios/nrpe.d/check_nova-compute.cfg:command[check_nova-compute]=/usr/local/lib/nagios/plugins/check_upstart_job nova-compute
/etc/nagios/nrpe.d/check_libvirt-bin.cfg:command[check_libvirt-bin]=/usr/local/lib/nagios/plugins/check_upstart_job libvirt-bin

but it misses to check required services when related to
neutron-plugin, e.g. for neutron-plugin-openvswitch-agent
it should also check for:
- openvswitch-switch
- neutron-plugin-openvswitch-agent

These checks 'logically' belong to the subordinate plugin charm
(neutron-openvswitch in this case), but afaiu it would be cumbersome
to have the nrpe checks *implemented* there, as it'd require
a *2nd* nrpe relation as subordinate<->subordinate:

juju add-relation nrpe-external-master neutron-openvswitch

, alonside already existing:

juju add-relation nrpe-external-master nova-compute

I'm not even sure that subord<->subord relations are supported, or
considered a good practice.

[JuanJo Ciarlante (jjo)]

FYI a PoC addition to nova-compute that implements these checks when
related to neutron-openvswitch: http://paste.ubuntu.com/14297836/
(note it also adds a check for OVS tun_ids to match neutron provider:segment_id)

[Lorenzo Cavassa (lorenzo-cavassa)]

Hi,

This bug affects also a deployment on which I'm working on. No N-G and just local DHCP/Metadata services on the the compute nodes.
It would be really helpful to get those checks set up during the relation creation between nrpe and neuntron-openvswitch.

[Alvaro Uria (aluria)]

Hi,

I've updated Juanjo's script at [0]: 1) minor rewrite for py3, 2) works on keystonev3 environments.

Since the type of neutron-plugin is configured on charm-neutron-api, but charm-neutron-openvswitch is related to charm-nova-compute, I think this fix should be added in charm-neutron-openvswitch.

According to [1], nrpe-external-master relation doesn't exist, and I think "juju add-relation neutron-openvswitch:nrpe-external-master nrpe:nrpe-external-master" should trigger the addition of this check.

Output looks like:
"""
OK: all needed tun_ids present: [1031, 1064, 1097, 1128, 1041, 1078]
"""

NRPE check would need to be split in two:
1) cronjob run as nova user: 1) will have access to /etc/nova/nova.conf to gather keystone credentials to list instances, networks and ports; 2) will need to use rootwrap which enables "ovs-ofctl" command run_as root

2) nrpe check which parses generated output by step #1

0. https://pastebin.canonical.com/p/5jSJzW8t5V/
1. https://github.com/openstack/charm-neutron-openvswitch/blob/master/metadata.yaml

[Chris MacNaughton (chris.macnaughton)]

As this is new feature work, and there is no proposal to add these features, I don't believe this should be subscribed to field-medium.