Mcollective Talk

A Mcollective talk i gave at Sydeney Devops

Transcript

1. Marionette Collective The awesomeness that is Wednesday, 20 March 13
2. What is it • Framework for system management (getting stuff done) • Orchestration • Real time interrogation Wednesday, 20 March 13
3. Luke Kaynes •“MCollective is like a chainsaw, taped to a chainsaw, swinging in the air. Wednesday, 20 March 13
4. What can it do • System Discovery • Task execution • Inventory Collection • Configuration / Package management (Puppet) Wednesday, 20 March 13
5. So why is it cool • No centralized inventory (real time) • Super scale • Framework for creating more stuff • Asynchronous Wednesday, 20 March 13
6. How • One client • Provides data • executes tasks • applies filters Wednesday, 20 March 13
7. Build blocks • Mcollective • Message Que • RPC • Client • Topic • Middleware • Server • Broker • Agent Wednesday, 20 March 13
8. What does that mean • Sender • Receiver • Request - message • Message transfer (Activemq) • Response - message Wednesday, 20 March 13
9. Example • Client(Sender) -> Middleware (ActiveMq) - > Server (Agent) • Example • mco ping --with-fact Kernel=linux • Facter is used • All machines receive the message Wednesday, 20 March 13
10. What is activemq • Data store that you can write and read from • Like email • You subscribe to a topic Wednesday, 20 March 13
11. Mcollective • The software than uses the middleware • Agent performs operation based on the message Wednesday, 20 March 13
12. Client • Process running on your server • Has many agents to perform commands • Send the output back to the client • Mcollective has in build filtering Wednesday, 20 March 13
13. Agents cont • You can write agents • SimpleRPC (Framework) • Written in ruby Wednesday, 20 March 13
14. Running an agent • mco rpc (agentname) (action) --with-fact (factname) = (value) • mco rpc nrpe runcommand command=check-load --with-fact kernel=linux Wednesday, 20 March 13
15. NRPE Mcollective mco rpc nrpe runcommand command=check-load --with-fact kernel=linux  *  [  ============================================================>  ]  3  /  3 Finished  processing  3  hosts  in  329.93  ms                            OK:  3                  WARNING:  0                CRITICAL:  0                  UNKNOWN:  0 }}} Wednesday, 20 March 13
16. By  default  it  only  shows  the  problems: {{{ %  mco  nrpe  check_disks  *   [   ============================================================>   ]  43  /  43 your.box.net                                            status=CRITICAL Finished  processing  43  hosts  in  439.98  ms                            OK:  42                  WARNING:  0                CRITICAL:  1                  UNKNOWN:  0 }}} Wednesday, 20 March 13
17. To  see  all  the  statusses: {{{ %  mco  nrpe  -­‐W  /dev_server/  check_load  -­‐v Determining  the  amount  of  hosts  matching  filter  for  2  seconds  ....  3  *  [  ============================================================>  ]  3  /  3 dev1.your.net                                            status=OK        OK  -­‐  load  average:  0.00,  0.00,  0.00           dev2.your.net                                            status=OK        OK  -­‐  load  average:  0.00,  0.00,  0.00           dev3.your.net                                            status=OK        OK  -­‐  load  average:  0.00,  0.00,  0.00           -­‐-­‐-­‐-­‐  check_load  NRPE  results  -­‐-­‐-­‐-­‐                      Nodes:  3          Pass  /  Fail:  3  /  0            Start  Time:  Tue  Dec  29  22:24:10  +0000  2009    Discovery  Time:  2006.46ms            Agent  Time:  334.85ms            Total  Time:  2341.31ms Nagios  Statusses:                            OK:  3                  WARNING:  0                CRITICAL:  0                  UNKNOWN:  0 Wednesday, 20 March 13
18. Orchestration • We want to upgrade our server to x version of the software • If its all good then we upgrade more Wednesday, 20 March 13
19. Problem • Find the loadbalancers • Find the webservers in the cluster • Make sure the loadbalancers are alive • Mark the webserver as down • Upgrade the application • Use nrpe to make sure its all good • Mark the webservers as alive • Rinse and repeat Wednesday, 20 March 13
20. The code Wednesday, 20 March 13