一、Jinja模板簡介
Jinja是一種基於python的模板引擎,在SLS文件裏可以直接使用jinja模板來做一些操作。
通過jinja模板可以爲不同服務器定義各自的變量。
兩種分隔符: {% ... %}
和 {{ ... }}
,前者用於執行諸如 for 循環 或賦值的語句,後者把表達式的結果打印到模板上(引用)。
二、Jinja模板使用方式
使用控制結構包裝條件
Jinja最基本的用法是使用控制結構包裝條件:
[root@server1 salt]# vim test.sls
[root@server1 salt]# cat test.sls
/mnt/testfile:
file.append:
{% if grains['fqdn'] == 'server2' %}
- text: server2
{% elif grains['fqdn'] == 'server3' %}
- text: server3
{% endif %}
以上文件的內容表示在server2和server3創建文件/mnt/testfile
,並將不同的內容添加進入文件。
推送:
[root@server1 salt]# salt '*' state.sls test
在server2查看:
[root@server2 ~]# cd /mnt/
[root@server2 mnt]# cat testfile
server2
在server3查看:
[root@server3 ~]# cd /mnt/
[root@server3 mnt]# cat testfile
server3
在普通文件的使用
Jinja在普通文件的使用:
[root@server1 salt]# cd apache/
[root@server1 apache]# vim init.sls
[root@server1 apache]# cat init.sls
apache:
pkg.installed:
- pkgs:
- {{ pillar['webserver'] }}
service.running:
- name: httpd
- reload: true
- enable: true
- watch:
- file: /etc/httpd/conf/httpd.conf
/etc/httpd/conf/httpd.conf:
file.managed:
- source: salt://apache/httpd.conf
- template: jinja
- context:
bind: 172.25.63.3
port: 80
其中:
- template: jinja #啓用jinja模板
- context:
bind: 172.25.63.3 #定義變量
port: 80
表示啓用jinja模板和定義變量,接下來在配置文件中調用變量:
[root@server1 apache]# vim httpd.conf
[root@server1 apache]# cat -n httpd.conf | grep 42
42 Listen {{ bind }}:{{ port }}
推送(由於ip已經設置,故推送給server3):
[root@server1 apache]# salt server3 state.sls apache
推送成功,在server3查看:
[root@server3 ~]# netstat -antlpe | grep 80
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 0 34667 3047/nginx: master
查看配置文件:
[root@server3 ~]# cat -n /etc/httpd/conf/httpd.conf | grep 42
42 Listen 172.25.63.3:80
從配置文件可以看出變量成功調用。
但是這種方式在主機數量增多後就不太合適,我們可以結合grains和pillar來進行調用:
[root@server1 apache]# vim init.sls
[root@server1 apache]# cat init.sls
apache:
pkg.installed:
- pkgs:
- {{ pillar['webserver'] }}
service.running:
- name: httpd
- reload: true
- enable: true
- watch:
- file: /etc/httpd/conf/httpd.conf
/etc/httpd/conf/httpd.conf:
file.managed:
- source: salt://apache/httpd.conf
- template: jinja
- context:
bind: {{ grains['ipv4'] }}
port: 80
但是這種方式調用時,grains['ipv4']
是個列表:
[root@server1 apache]# salt server3 grains.item ipv4
server3:
----------
ipv4:
- 127.0.0.1
- 172.25.63.3
在推送時就會有問題:
[root@server1 apache]# salt server3 state.sls apache
可以看出apache並不支持列表的形式,因此我們可以使用切片(與python的切片方法相同):
[root@server1 apache]# vim init.sls
[root@server1 apache]# cat init.sls
apache:
pkg.installed:
- pkgs:
- {{ pillar['webserver'] }}
service.running:
- name: httpd
- reload: true
- enable: true
- watch:
- file: /etc/httpd/conf/httpd.conf
/etc/httpd/conf/httpd.conf:
file.managed:
- source: salt://apache/httpd.conf
- template: jinja
- context:
bind: {{ grains['ipv4'][-1] }}
port: 80
再次推送:
[root@server1 apache]# salt server3 state.sls apache
可以看出推送成功。
我們也可以將port變量調用pillar的值:
[root@server1 apache]# vim init.sls
[root@server1 apache]# cat init.sls
apache:
pkg.installed:
- pkgs:
- {{ pillar['webserver'] }}
service.running:
- name: httpd
- reload: true
- enable: true
- watch:
- file: /etc/httpd/conf/httpd.conf
/etc/httpd/conf/httpd.conf:
file.managed:
- source: salt://apache/httpd.conf
- template: jinja
- context:
bind: {{ grains['ipv4'][-1] }}
port: {{ pillar['port'] }}
推送:
[root@server1 apache]# salt server3 state.sls apache
成功推送。
此時更改pillar的信息:
[root@server1 pillar]# vim web.sls
[root@server1 pillar]# cat web.sls
{% if grains['fqdn'] == 'server3' %}
webserver: httpd
port: 8080
{% elif grains['fqdn'] == 'server2' %}
webserver: nginx
port: 80
{% endif %}
將server3的端口改爲8080,推送:
[root@server1 apache]# salt server3 state.sls apache
在server3查看端口:
[root@server3 ~]# netstat -antlpe | grep 8080
tcp 0 0 172.25.63.3:8080 0.0.0.0:* LISTEN 0 45425 3749/httpd
可以看出已經更改爲8080.
當然也可以直接在配置文件中調用grains或者pillar:
[root@server1 apache]# vim init.sls
[root@server1 apache]# cat init.sls
apache:
pkg.installed:
- pkgs:
- {{ pillar['webserver'] }}
service.running:
- name: httpd
- reload: true
- enable: true
- watch:
- file: /etc/httpd/conf/httpd.conf
/etc/httpd/conf/httpd.conf:
file.managed:
- source: salt://apache/httpd.conf
- template: jinja #注意需要啓用jinja模板
[root@server1 apache]# vim httpd.conf
[root@server1 apache]# cat -n httpd.conf | grep 42
42 Listen {{ grains['ipv4'][-1] }}:{{ pillar['port'] }}
然後推送:
[root@server1 apache]# salt server3 state.sls apache
可以看出推送成功。
import方式
第三種方式爲import方式,可在state文件之間共享:
定義變量文件:
[root@server1 salt]# vim lib.sls
[root@server1 salt]# cat lib.sls
{% set port = 80 %}
導入模板文件:
[root@server1 salt]# cd apache/
[root@server1 apache]# vim httpd.conf
[root@server1 apache]# head -1 httpd.conf
{% from 'lib.sls' import port %}
調用變量:
[root@server1 apache]# cat -n httpd.conf | grep 43
43 Listen {{ grains['ipv4'][-1] }}:{{ port }}
推送:
[root@server1 apache]# salt server3 state.sls apache
在server3查看可以看出配置已經生效:
[root@server3 ~]# netstat -antlpe | grep httpd
tcp 0 0 172.25.63.3:80 0.0.0.0:* LISTEN 0 45983 3749/httpd
但是我們先在考慮一個問題,如果我們不僅在init文件中定義了變量port,還用import方式定義了變量,當調用的時候哪個優先級高呢,通過實驗看下結果:
在init文件中定義變量port爲8080(這裏調用的pillar,server3的pillar port爲8080):
[root@server1 apache]# vim init.sls
[root@server1 apache]# cat init.sls
apache:
pkg.installed:
- pkgs:
- {{ pillar['webserver'] }}
service.running:
- name: httpd
- reload: true
- enable: true
- watch:
- file: /etc/httpd/conf/httpd.conf
/etc/httpd/conf/httpd.conf:
file.managed:
- source: salt://apache/httpd.conf
- template: jinja
- context:
# bind: {{ grains['ipv4'][-1] }}
port: {{ pillar['port'] }}
import的方式我們上面已經設置過了,因此我們直接推送查看結果:
[root@server1 apache]# salt server3 state.sls apache
server3查看:
[root@server3 ~]# netstat -antlpe | grep httpd
tcp 0 0 172.25.63.3:80 0.0.0.0:* LISTEN 0 45983 3749/httpd
可以看出通過import的方式導入的變量優先級高於在init文件中定義的變量,原因是在運行的時候最後讀取的是import方式導入的變量。
注意:一般習慣將變量都定義在init文件中,然後在其他文件中引用即可。
三、Jinja模板應用之部署keepalived高可用集羣
我們這裏準備將server2設置爲master節點,server3爲backup節點,vip爲172.25.63.100
。
首先編輯init文件在節點安裝keepalived:
[root@server1 salt]# mkdir keepalived
[root@server1 salt]# cd keepalived/
[root@server1 keepalived]# vim init.sls
[root@server1 keepalived]# cat init.sls
install-kp:
pkg.installed:
- name: keepalived
推送測試:
[root@server1 keepalived]# salt '*' state.sls keepalived
安裝成功。
繼續編輯init文件,設置配置文件以及服務:
[root@server1 keepalived]# vim init.sls
[root@server1 keepalived]# cat init.sls
install-kp:
pkg.installed:
- name: keepalived
file.managed:
- name: /etc/keepalived/keepalived.conf
- source: salt://keepalived/keepalived.conf
service.running:
- name: keepalived
- reload: true
- watch:
- file: install-kp
複製配置文件:
[root@server1 keepalived]# scp server2:/etc/keepalived/keepalived.conf .
[root@server1 keepalived]# ls
init.sls keepalived.conf
編輯配置文件:
[root@server1 keepalived]# vim keepalived.conf
[root@server1 keepalived]# cat keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
172.25.63.100
}
}
可以看出配置文件中的角色爲master,優先級爲100,vip爲172.25.63.100。
推送給server2測試:
[root@server1 keepalived]# salt server2 state.sls keepalived
推送成功。
在server2查看日誌:
[root@server2 mnt]# tail -20 /var/log/messages
可以看出是master的身份,查看ip:
可以看出已經獲得了虛擬ip。
server2部署成功,但是現在有一個問題,server3(backup節點)的配置文件和server2不同,不能直接推送,我們可以結合jinja模板與pillar實現不同主機的配置文件不同。
更改配置文件:
[root@server1 keepalived]# vim keepalived.conf
[root@server1 keepalived]# cat keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
root@localhost
}
notification_email_from keepalived@localhost
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_instance VI_1 {
state {{ STATE }}
interface eth0
virtual_router_id 51
priority {{ PRI }}
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
{{ VIP }}
}
}
其中STATE、PRI、VIP爲變量,接下來我們就需要定義pillar變量:
[root@server1 keepalived]# cd /srv/pillar/
[root@server1 pillar]# vim web.sls
[root@server1 pillar]# cat web.sls
{% if grains['fqdn'] == 'server2' %}
kpstate: MASTER
kppri: 100
{% elif grains['fqdn'] == 'server3' %}
kpstate: BACKUP
kppri: 50
{% endif %}
在init文件中將pillar變量賦值給配置文件中的三個變量:
[root@server1 pillar]# cd -
/srv/salt/keepalived
[root@server1 keepalived]# vim init.sls
[root@server1 keepalived]# cat init.sls
install-kp:
pkg.installed:
- name: keepalived
file.managed:
- name: /etc/keepalived/keepalived.conf
- source: salt://keepalived/keepalived.conf
- template: jinja
- context:
STATE: {{ pillar['kpstate'] }} #將pillar變量賦值給配置文件中的三個變量
PRI: {{ pillar['kppri'] }}
VIP: {{ pillar['vip'] }}
service.running:
- name: keepalived
- reload: true
- watch:
- file: install-kp
現在可以直接推送給兩個節點:
[root@server1 keepalived]# salt '*' state.sls keepalived
配置成功。
在server2查看:
[root@server2 mnt]# tail -20 /var/log/messages
.......
May 18 23:34:05 server2 Keepalived_vrrp[3688]: VRRP_Instance(VI_1) Transition to MASTER STATE
可以看出已經獲得vip:
[root@server2 mnt]# ip addr
......
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 52:54:00:be:bf:d2 brd ff:ff:ff:ff:ff:ff
inet 172.25.63.2/24 brd 172.25.63.255 scope global eth0
valid_lft forever preferred_lft forever
inet 172.25.63.100/32 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::5054:ff:febe:bfd2/64 scope link
valid_lft forever preferred_lft forever
在server3查看:
[root@server3 ~]# tail -20 /var/log/messages
......
May 18 23:34:04 server3 Keepalived_vrrp[4100]: VRRP_Instance(VI_1) Entering BACKUP STATE
May 18 23:34:04 server3 Keepalived_vrrp[4100]: VRRP_Instance(VI_1) removing protocol VIPs.
可以看出已經部署完成。
接下來進行測試:
關閉server2的keepalived:
[root@server2 mnt]# systemctl stop keepalived
查看server3已經自動切換成了master節點並且得到了vip:
此時在server1再次進行推送:
[root@server1 keepalived]# salt '*' state.sls keepalived
推送後由於server2的服務會被啓動,且優先級(100)高於serve3(50),因此server2又會變成master節點:
高可用集羣成功部署。
也可以不使用pillar,直接將變量定義在init文件中,比如下面這種寫法和上面的效果是相同的:
[root@server1 keepalived]# vim init.sls
[root@server1 keepalived]#
[root@server1 keepalived]# cat init.sls
install-kp:
pkg.installed:
- name: keepalived
file.managed:
- name: /etc/keepalived/keepalived.conf
- source: salt://keepalived/keepalived.conf
- template: jinja
- context:
{% if grains['fqdn'] == 'server2' %}
STATE: MASTER
PRI: 100
VIP: 172.25.63.100
{% elif grains['fqdn'] == 'server3' %}
STATE: BACKUP
PRI: 50
VIP: 172.25.63.100
{% endif %}
service.running:
- name: keepalived
- reload: true
- watch:
- file: install-kp
當節點數量多時還是推薦結合pillar的方法。