Option 1: DNS importer

• salt generates one or more zone files
• opennms imports the zones:

<requisition-def import-name="linuxservers"
   import-url-resource="dns://salt/linuxservers">
  <cron-schedule>0 0 0 * * ? *</cron-schedule>
</requisition-def>
        

DNS zone generation in Salt

@ in soa localhost. root 1 3H 15M 1W 1D
  ns localhost.
{% set nets=salt['publish.publish']('*','network.interfaces') %}\
{% for n in nets %}{% set pdata=salt['publish.publish'](n,'pillar.data') %}\
{% if pdata.has_key(n) %}{% if pdata[n].has_key('zone') %}\
{% if pdata[n]['zone']=='linuxservers' %}
{{ n }} IN      A       {{ nets[n]['eth0']['inet'][0]['address'] }}
{% endif %}{% endif %}{% endif %}{% endfor %}

DNS: review

• ✓ no coding required
• ✓ provisioning aware
• ✘ still no metadata
• ✘ still no decommissioning

Option 2: Events

• salt 0.10.5 introduced python event APIs
• listen for key add/delete
• integrate with provisioning
• 0.11.0 improves API with builtin Reactors

Event listener service (started from inittab or upstart):

event = salt.utils.event.MasterEvent('/var/run/salt/master/')

evt_generator=event.iter_events(tag='key',full=True)
for data in evt_generator:
    payload = data['data']
    minion_id    = payload['id']
    if payload.get('act') == 'accept' and payload.get('result'):
        minion_id=("%s/%s" % ('add',minion_id))
    if payload.get('act') == 'delete' and payload.get('result'):
        minion_id=("%s/%s" % ('delete',minion_id))
    redis.rpush(salt_queue, "%s"%(minion_id))
        

Redis: shared queue and K/V store:

• listener pushes deleted/added minion ids to a queue
• consumer fetches ids (in order)
• consumer stores the opennms node id and requisition name:

  [root@srvdpis ~]# redis-cli get testserver.xxxxxxxxx
  "mainsite/55bc57cfdeaf95c3320facb6a95a3afce2475cbd"

Consumer process (started from crontab every 20'):

• locks queue
• process queue
• query minions for ip and metadata
• forks provision.pl calls
• supports dry-run mode

Events: review

• ✓ aligned with ops
• ✓ provisioning aware
• ✓ supports metadata
• ✓ supports decommissioning
• ✓ coding required (~ 200 LOC)