参考：刘天斯《Python自动化运维技术与最佳实践》
grains是Saltstack最重要的组件之一，grains的作用是收集被控主机的基本信息，这些信息通常都是一些静态类的数据，包括CPU、内核、操作系统、虚拟化等，在服务器端可以根据这些信息进行灵活定制，管理员可以利用这些信息对不同业务进行个性化定制。
获取所有主机的grains项信息，发现没有max_openfile,等会我们手动编写一个。
[root@salt-master base]# salt '*' grains.ls
salt-master:
- SSDs
- biosreleasedate
- biosversion
- cpu_flags
- cpu_model
- cpuarch
- disks
- dns
- domain
- fqdn
- fqdn_ip4
- fqdn_ip6
- gid
- gpus
- groupname
- host
- hwaddr_interfaces
- id
- init
- ip4_interfaces
- ip6_interfaces
- ip_interfaces
- ipv4
- ipv6
- kernel
- kernelrelease
- locale_info
- localhost
- lsb_distrib_codename
- lsb_distrib_id
- machine_id
- manufacturer
- master
- mdadm
- mem_total
- nodename
- num_cpus
- num_gpus
- os
- os_family
- osarch
- oscodename
- osfinger
- osfullname
- osmajorrelease
- osrelease
- osrelease_info
- path
- pid
- productname
- ps
- pythonexecutable
- pythonpath
- pythonversion
- saltpath
- saltversion
- saltversioninfo
- selinux
- serialnumber
- server_id
- shell
- systemd
- uid
- username
- uuid
- virtual
- zmqversion
salt-minion01:
- SSDs
- cpu_flags
- cpu_model
- cpuarch
- disks
- dns
- domain
- fqdn
- fqdn_ip4
- fqdn_ip6
- gid
- gpus
- groupname
- host
- hwaddr_interfaces
- id
- init
- ip4_interfaces
- ip6_interfaces
- ip_interfaces
- ipv4
- ipv6
- kernel
- kernelrelease
- locale_info
- localhost
- lsb_distrib_codename
- lsb_distrib_id
- lsb_distrib_release
- master
- max_open_file
- mdadm
- mem_total
- nodename
- num_cpus
- num_gpus
- os
- os_family
- osarch
- oscodename
- osfinger
- osfullname
- osmajorrelease
- osrelease
- osrelease_info
- path
- pid
- ps
- pythonexecutable
- pythonpath
- pythonversion
- saltpath
- saltversion
- saltversioninfo
- selinux
- server_id
- shell
- uid
- username
- virtual
- zmqversion
hddcluster2:
- SSDs
- biosreleasedate
- biosversion
- cpu_flags
- cpu_model
- cpuarch
- disks
- dns
- domain
- fqdn
- fqdn_ip4
- fqdn_ip6
- gid
- gpus
- groupname
- host
- hwaddr_interfaces
- id
- init
- ip4_interfaces
- ip6_interfaces
- ip_interfaces
- ipv4
- ipv6
- kernel
- kernelrelease
- locale_info
- localhost
- lsb_distrib_codename
- lsb_distrib_id
- lsb_distrib_release
- machine_id
- manufacturer
- master
- mdadm
- mem_total
- nodename
- num_cpus
- num_gpus
- os
- os_family
- osarch
- oscodename
- osfinger
- osfullname
- osmajorrelease
- osrelease
- osrelease_info
- path
- pid
- productname
- ps
- pythonexecutable
- pythonpath
- pythonversion
- saltpath
- saltversion
- saltversioninfo
- selinux
- serialnumber
- server_id
- shell
- systemd
- uid
- username
- uuid
- virtual
- zmqversion
hddcluster4:
- SSDs
- biosreleasedate
- biosversion
- cpu_flags
- cpu_model
- cpuarch
- disks
- dns
- domain
- fqdn
- fqdn_ip4
- fqdn_ip6
- gid
- gpus
- groupname
- host
- hwaddr_interfaces
- id
- init
- ip4_interfaces
- ip6_interfaces
- ip_interfaces
- ipv4
- ipv6
- kernel
- kernelrelease
- locale_info
- localhost
- lsb_distrib_codename
- lsb_distrib_id
- lsb_distrib_release
- machine_id
- manufacturer
- master
- mdadm
- mem_total
- nodename
- num_cpus
- num_gpus
- os
- os_family
- osarch
- oscodename
- osfinger
- osfullname
- osmajorrelease
- osrelease
- osrelease_info
- path
- pid
- productname
- ps
- pythonexecutable
- pythonpath
- pythonversion
- saltpath
- saltversion
- saltversioninfo
- selinux
- serialnumber
- server_id
- shell
- systemd
- uid
- username
- uuid
- virtual
- zmqversion
hddcluster3:
- SSDs
- biosreleasedate
- biosversion
- cpu_flags
- cpu_model
- cpuarch
- disks
- dns
- domain
- fqdn
- fqdn_ip4
- fqdn_ip6
- gid
- gpus
- groupname
- host
- hwaddr_interfaces
- id
- init
- ip4_interfaces
- ip6_interfaces
- ip_interfaces
- ipv4
- ipv6
- kernel
- kernelrelease
- locale_info
- localhost
- lsb_distrib_codename
- lsb_distrib_id
- lsb_distrib_release
- machine_id
- manufacturer
- master
- mdadm
- mem_total
- nodename
- num_cpus
- num_gpus
- os
- os_family
- osarch
- oscodename
- osfinger
- osfullname
- osmajorrelease
- osrelease
- osrelease_info
- path
- pid
- productname
- ps
- pythonexecutable
- pythonpath
- pythonversion
- saltpath
- saltversion
- saltversioninfo
- selinux
- serialnumber
- server_id
- shell
- systemd
- uid
- username
- uuid
- virtual
- zmqversion
hddcluster1:
- SSDs
- biosreleasedate
- biosversion
- cpu_flags
- cpu_model
- cpuarch
- disks
- dns
- domain
- fqdn
- fqdn_ip4
- fqdn_ip6
- gid
- gpus
- groupname
- host
- hwaddr_interfaces
- id
- init
- ip4_interfaces
- ip6_interfaces
- ip_interfaces
- ipv4
- ipv6
- kernel
- kernelrelease
- locale_info
- localhost
- lsb_distrib_codename
- lsb_distrib_id
- lsb_distrib_release
- machine_id
- manufacturer
- master
- mdadm
- mem_total
- nodename
- num_cpus
- num_gpus
- os
- os_family
- osarch
- oscodename
- osfinger
- osfullname
- osmajorrelease
- osrelease
- osrelease_info
- path
- pid
- productname
- ps
- pythonexecutable
- pythonpath
- pythonversion
- saltpath
- saltversion
- saltversioninfo
- selinux
- serialnumber
- server_id
- shell
- systemd
- uid
- username
- uuid
- virtual
- zmqversio
定义grains数据的方法有两种，一种为在被控主机定制配置文件：另一种是通过主控端扩展模块API实现。
我这这里直说主控端，毕竟我们要搞自动化运维，需要批量操作。
主控端扩展模块定制grains数据
vim /etc/salt/master
file_roots:
base: //基础平台
- /srv/salt/base
prod: //生产平台
- /srv/salt/prod
install -d /srv/salt/base/_grains
vim /srv/salt/base/_grains/grains_openfile.py //编写一个python脚本获取max_openfile的值
#!/usr/bin/env python
# -*- coding:utf-8 -*-
import os,sys,commands
#定义一个获取最大打开文件数的函数，函数名称没有要求，符合python函数命名规则即可
def Grains_openfile():
'''
return os max open file of grains value
'''
grains = {} #初始化一个字典，变量名一定要用grains,以便Saltstack识别
_open_file=65535 #初始化一个默认值
try:
getulimit = commands.getstatusoutput('source /etc/profile;ulimit -n')
except Exception,e:
pass
if getulimit[0]==0:
_open_file=int(getulimit[1])
grains['max_open_file'] = _open_file #将获取的ulimit -n的结果进行赋值，其中'max_open_file'就是grains项，——open_file就是grains的值
return grains
最后同步模块到指定被控主机并刷新生效，因为grains比较适合采集静态类的数据，比如硬件、内核信息等，当有动态类的功能需求时，需要进行刷新。
同步操作：
服务端master
[root@salt-master base]# salt 'salt-minion01' saltutil.sync_all
salt-minion01:
----------
beacons:
engines:
grains:
- grains.grains_openfile
log_handlers:
modules:
output:
proxymodules:
renderers:
returners:
sdb:
states:
utils:
客户端minion
结果：文件同步到被控端的cache目录中
[root@salt-minion01 ~]# find / -type f -name grains_openfile.py
/var/cache/salt/minion/files/base/_grains/grains_openfile.py
/var/cache/salt/minion/extmods/grains/grains_openfile.py
#注：/var/cache/salt/minion/extmods/grains/为扩展模块文件最终存放位置，刷新模块后将在同路径下生产字节码pyc；/var/cache/salt/minion/files/base/_grains/为临时存放位置。
刷新操作:
[root@salt-master base]# salt 'salt-minion01' sys.reload_modules
salt-minion01:
True
[root@salt-minion01 ~]# find / -type f -name grains_openfile.py*
/var/cache/salt/minion/files/base/_grains/grains_openfile.py
/var/cache/salt/minion/extmods/grains/grains_openfile.pyc //多了一个pyc
/var/cache/salt/minion/extmods/grains/grains_openfile.py
查看同步后是否能正常获取数据
[root@salt-master base]# salt 'salt-minion01' grains.item max_open_file
salt-minion01:
----------
max_open_file:
1024
其他未同步的，并不会有max_open_file数据
[root@salt-master base]# salt '*' grains.item max_open_file
salt-master:
----------
max_open_file:
salt-minion01:
----------
max_open_file:
1024
hddcluster2:
----------
max_open_file:
hddcluster4:
----------
max_open_file:
hddcluster3:
----------
max_open_file:
hddcluster1:
----------
max_open_file:
[root@salt-master base]#
其他未同步的，并不会有max数据，也没有这个模块
[root@salt-master base]# salt '*' grains.item max
salt-master:
----------
max:
hddcluster2:
----------
max:
salt-minion01:
----------
max:
hddcluster3:
----------
max:
hddcluster4:
----------
max:
hddcluster1:
----------
max:
最后再试一下吧，同步所有机器，再刷新所有机器
[root@salt-master base]# salt '*' saltutil.sync_all
salt-master:
----------
beacons:
engines:
grains:
- grains.grains_openfile
log_handlers:
modules:
output:
proxymodules:
renderers:
returners:
sdb:
states:
utils:
salt-minion01: //这个同步过了，没有更新
----------
beacons:
engines:
grains:
log_handlers:
modules:
output:
proxymodules:
renderers:
returners:
sdb:
states:
utils:
hddcluster2:
----------
beacons:
engines:
grains:
- grains.grains_openfile
log_handlers:
modules:
output:
proxymodules:
renderers:
returners:
sdb:
states:
utils:
hddcluster3:
----------
beacons:
engines:
grains:
- grains.grains_openfile
log_handlers:
modules:
output:
proxymodules:
renderers:
returners:
sdb:
states:
utils:
hddcluster4:
----------
beacons:
engines:
grains:
- grains.grains_openfile
log_handlers:
modules:
output:
proxymodules:
renderers:
returners:
sdb:
states:
utils:
hddcluster1:
----------
beacons:
engines:
grains:
- grains.grains_openfile
log_handlers:
modules:
output:
proxymodules:
renderers:
returners:
sdb:
states:
utils:
[root@salt-master base]# salt '*' sys.reload_modules
salt-master:
True
salt-minion01:
True
hddcluster2:
True
hddcluster4:
True
hddcluster3:
True
hddcluster1:
True
[root@salt-master base]# salt '*' grains.item max_open_file
salt-master:
----------
max_open_file:
8192
hddcluster2:
----------
max_open_file:
salt-minion01:
----------
max_open_file:
1024
hddcluster3:
----------
max_open_file:
8192
hddcluster4:
----------
max_open_file:
8192
hddcluster1:
----------
max_open_file:
8192
至此，已经测试完毕，需要写其他模块，可以在_grains目录下继续添加。