Configuration management is the process of standardizing and enforcing resource configurations across IT infrastructure in an automated way. An example is setting a policy that the SNMP service must be installed and running. This can be defined using YAML and specifying that the net-snmp package must be installed and the SNMP daemon service must be enabled and running. Jinja templating allows variables like the location and contact details to be set using pillar data and different configurations to be set based on the operating system grains. States can then be applied to nodes using Salt functions to configure systems according to the defined policies and pillars in an automated and consistent manner.

1. For Beginners – pt. 2
Configuration Management

2. Who am I?
ber
Um
etti
icol
oN
t
●
Sysadmin
●
PSC
Dev
●
Open Source
enthusiast
contributor
contributor
@afactotum

3. Riassunto della puntata prec.
Remote Execution
http://prezi.com/user/unicoletti/

4. Configuration Management
Configuration management is the
process of standardizing resource
configurations and enforcing their
state across IT infrastructure in an
automated yet agile manner.

5. Un esempio...
Policy: il servizio
snmp deve essere
installato ed in
esecuzione
YA
M
L!
net-snmp:
pkg:
- installed
service:
- name: snmpd
- enable: True
- running
- require:
- pkg: net-snmp

6. L'esempio continua...
/etc/snmpd.conf:
Gestiamo
anche
la cfg del
servizio
file.managed:
- source: salt://snmp/snmpd.conf
- user: root
- group: root
- mode: 640
- template: jinja

7. Jinja Templating
syslocation "Pd, Veneto, Italy, Europe"
syscontact root@example.org
rocommunity sssshhhhh
disk /
Q ue s t e
stringhe
dev o n o
diventa
re
variabili
syslocation {{ pillar['location'] }}
syscontact {{ pillar['contact'] }}
rocommunity {{ pillar['rocommunity'] }}
disk /

8. Pillar of Salt
Pillar is an interface for
Salt designed to offer
global values that can
be distributed to all
minions.
●
Jinja templates usano
–
pillar data
–
grains

9. Gestione multipli OS
net-snmp:
pkg:
{% if grains['os'] == 'Ubuntu'%}
- name: snmpd
{% endif%}
- installed
service:
- name: snmpd
- enable: True
- running
- require:
- pkg: net-snmp

10. Ricapitolando...
GRAINS
PILLAR DATA
TEMPLATES
STATI
SALT FUNCTIONS

11. Applicare gli stati
●
Da master:
–
●
salt state.highstate
Da minion
–
salt-call state.highstate
Anche modalita'
master-less

12. TOP: assegnare stati/pillar ai nodi
TOP FILE
●
base:
'*':
- snmpd
●
●
top.sls
associa
stati ai nodi
associa
pillar ai nodi

13. Un esempio reale(istico)
SENTRY
POSTGRES + DJANGO + NGINX
Centos + Vagrant
https://github.com/unicolet/salt-sentry

14. Configuration Mgmt: benefici
Automazione
Documentazione, Visibilita'
Compliance
Efficienza
Affidabilita'
Testability
Agilita'