PXE: DHCP通过CMDB的API自动渲染配置文件脚本

7-29 DEVOPS,PYTHON Eric Winn 9 views

PXE: DHCP通过CMDB的API自动渲染配置文件脚本

7-29 9 views

背景

考虑要通过mac指定安装不同的操作系统，首先这些信息都已经录入到了CMDB中，通过API可以获取到,如下样例:

[{
	'number': '192.168.1.103',
	'ip': '192.168.1.103',
	'raid': None,
	'get_os': 'RedHat 6.8',
	'get_pxe': 'PXE',
	'get_rsync_flg': 'False',
	'get_raid': None,
	'get_ip': None,
	'get_mac': '22:44:FF:77:44:78'
}, {
	'number': '192.168.1.132',
	'ip': '192.168.1.132',
	'raid': None,
	'get_os': 'CentOS 7.3',
	'get_pxe': 'PXE',
	'get_rsync_flg': 'False',
	'get_raid': None,
	'get_ip': None,
	'get_mac': '22:00:FF:EE:44:74'
}]

[{

'number': '192.168.1.103',

'ip': '192.168.1.103',

'raid': None,

'get_os': 'RedHat 6.8',

'get_pxe': 'PXE',

'get_rsync_flg': 'False',

'get_raid': None,

'get_ip': None,

'get_mac': '22:44:FF:77:44:78'

}, {

'number': '192.168.1.132',

'ip': '192.168.1.132',

'raid': None,

'get_os': 'CentOS 7.3',

'get_pxe': 'PXE',

'get_rsync_flg': 'False',

'get_raid': None,

'get_ip': None,

'get_mac': '22:00:FF:EE:44:74'

}]

准备工作

dhcp模板

个人习惯，我在脚本的所在目录下，创建了一个子目录“templates”，并将我的dhcp模板文件放在这个目录名，并取名叫”dhcpd.conf.j2″

[root@localhost ~]# vim templates/dhcpd.conf.j2 
default-lease-time 600;
max-lease-time 7200;

log-facility local7;

subnet {{ network.get('subnet')[0] }} netmask {{ network.get('subnet')[1] }} {
    range {{ network.get('subnet_range')[0] }} {{ network.get('subnet_range')[1] }};
    option routers {{ network.get('gateway') }};
}

{% for hostname,server_info in pxe_server.items() %}
host {{ hostname }} {
    hardware ethernet {{server_info["mac"] }};
    next-server {{ network.get('gateway') }};
    fixed-address {{ server_info["ip"] }};
    filename "{{ server_info["pxe_os"] }}/pxelinux.0";

}
{% endfor %}

[root@localhost ~]# vim templates/dhcpd.conf.j2

default-lease-time 600;

max-lease-time 7200;

log-facility local7;

subnet {{ network.get('subnet')[0] }} netmask {{ network.get('subnet')[1] }} {

range {{ network.get('subnet_range')[0] }} {{ network.get('subnet_range')[1] }};

option routers {{ network.get('gateway') }};

}

{% for hostname,server_info in pxe_server.items() %}

host {{ hostname }} {

hardware ethernet {{server_info["mac"] }};

next-server {{ network.get('gateway') }};

fixed-address {{ server_info["ip"] }};

filename "{{ server_info["pxe_os"] }}/pxelinux.0";

}

{% endfor %}

渲染脚本

[root@localhost ~]# vim dhcp_flush.py 
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Author         : Eric Winn 
# @Email          : eng.eric.winn@gmail.com 
# @Time           : 2018-05-18 13:46
# @Version        : 1.0
# @File           : dhcp_flush
# @Software       : PyCharm

import sys
import json
import datetime

# DHCP
network = {
    'subnet': [
        '192.168.1.0',
        '255.255.255.0'
    ],
    'subnet_range': [
        '192.168.1.100',
        '192.168.1.200'
    ],
    'gateway': '192.168.1.1',
    'nextserver': '192.168.1.55'   #pxe server
}

token = 'aaaaaae1909768eebbbbbbd51886eeeeeeeeeeee'
host = '10.9.54.4'
headers = {'Authorization': 'token ' + token}
url = "http://{host}/api/assets/v1/pxe-assets/".format(host=host)

#模板文件所在目录
templateDir = './templates'

template_list = {
    'dhcp': [
        'dhcpd.conf.j2',  #dhcp模板文件
        '/etc/dhcp/', # dhcp配置文件目录
    ],
}


class render_file():
    def __init__(self, templateDir, templates):
        try:
            from jinja2 import FileSystemLoader, Environment
        except ImportError as e:
            print('%s\nPlease use `pip install -r requirements.txt` to install.' % e)
            sys.exit(0)

        TemplateLoader = FileSystemLoader(searchpath=templateDir)
        TemplateEnv = Environment(loader=TemplateLoader)
        self.template = TemplateEnv.get_template(templates[0])
        self.exportFileName = templates[0] + datetime.datetime.now().strftime('%Y-%m-%-d-%H-%M-%S')
        self.service_config_file_name = templates[1]
        self.result = None

    def make(self, get_pxe_server_list, network=None):
        # 渲染
        self.result = self.template.render(pxe_server=get_pxe_server_list, network=network)

    def export(self, filename, key=None):
        with open(self.exportFileName, 'w') as f:
            f.write(self.result)

        import shutil
        from subprocess import call

        # 将渲染后的dhcp配置文件copy到dhcp配置文件目录下，覆盖已有的配置文件
        shutil.copy(self.exportFileName, self.service_config_file_name + filename)

        # dhcp配置文件渲染后，重启dhcp服务
        if key == 'dhcp':
            sys_ret = call("systemctl restart dhcpd", shell=True)
            if sys_ret:
                SystemError({'msg': 'dhcpd start is failed'})


def get_pxe_server_list():
    try:
        import requests
    except ImportError as e:
        print('%s\nPlease use `pip install -r requirements.txt` to install.' % e)
        sys.exit(0)
    # 调用api
    req = requests.get(url, headers=headers)
    req = json.loads(req.text)
    pxe_server = dict()
    # 获取需要的字段，用于渲染
    for item in req:
        sie = {}
        sie['ip'] = item['ip']
        sie['mac'] = item.get('get_mac', None)
        if not item['get_os']: continue
        sie['pxe_os'] = str(item['get_os']).replace(' ', '.')

        pxe_server[item['number']] = sie
    return pxe_server


if __name__ == '__main__':
    pxe_server_list = get_pxe_server_list()
    print(pxe_server_list)
    if not len(pxe_server_list):
        print('没有获取到要安装系统的主机')
        SystemExit(1)

    # dhcp
    render = render_file(templateDir, template_list.get('dhcp'))
    render.make(pxe_server_list, network)
    render.export('dhcpd.conf', 'dhcp')

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[root@localhost ~]# vim dhcp_flush.py

#!/usr/bin/env python

# -*- coding: utf-8 -*-

# @Author : Eric Winn

# @Email : eng.eric.winn@gmail.com

# @Time : 2018-05-18 13:46

# @Version : 1.0

# @File : dhcp_flush

# @Software : PyCharm

import sys

import json

import datetime

# DHCP

network = {

'subnet': [

'192.168.1.0',

'255.255.255.0'

'subnet_range': [

'192.168.1.100',

'192.168.1.200'

'gateway': '192.168.1.1',

'nextserver': '192.168.1.55' #pxe server

}

token = 'aaaaaae1909768eebbbbbbd51886eeeeeeeeeeee'

host = '10.9.54.4'

headers = {'Authorization': 'token ' + token}

url = "http://{host}/api/assets/v1/pxe-assets/".format(host=host)

#模板文件所在目录

templateDir = './templates'

template_list = {

'dhcp': [

'dhcpd.conf.j2', #dhcp模板文件

'/etc/dhcp/', # dhcp配置文件目录

}

class render_file():

def __init__(self, templateDir, templates):

try:

from jinja2 import FileSystemLoader, Environment

except ImportError as e:

print('%s\nPlease use `pip install -r requirements.txt` to install.' % e)

sys.exit(0)

TemplateLoader = FileSystemLoader(searchpath=templateDir)

TemplateEnv = Environment(loader=TemplateLoader)

self.template = TemplateEnv.get_template(templates[0])

self.exportFileName = templates[0] + datetime.datetime.now().strftime('%Y-%m-%-d-%H-%M-%S')

self.service_config_file_name = templates[1]

self.result = None

def make(self, get_pxe_server_list, network=None):

# 渲染

self.result = self.template.render(pxe_server=get_pxe_server_list, network=network)

def export(self, filename, key=None):

with open(self.exportFileName, 'w') as f:

f.write(self.result)

import shutil

from subprocess import call

# 将渲染后的dhcp配置文件copy到dhcp配置文件目录下，覆盖已有的配置文件

shutil.copy(self.exportFileName, self.service_config_file_name + filename)

# dhcp配置文件渲染后，重启dhcp服务

if key == 'dhcp':

sys_ret = call("systemctl restart dhcpd", shell=True)

if sys_ret:

SystemError({'msg': 'dhcpd start is failed'})

def get_pxe_server_list():

try:

import requests

except ImportError as e:

print('%s\nPlease use `pip install -r requirements.txt` to install.' % e)

sys.exit(0)

# 调用api

req = requests.get(url, headers=headers)

req = json.loads(req.text)

pxe_server = dict()

# 获取需要的字段，用于渲染

for item in req:

sie = {}

sie['ip'] = item['ip']

sie['mac'] = item.get('get_mac', None)

if not item['get_os']: continue

sie['pxe_os'] = str(item['get_os']).replace(' ', '.')

pxe_server[item['number']] = sie

return pxe_server

if __name__ == '__main__':

pxe_server_list = get_pxe_server_list()

print(pxe_server_list)

if not len(pxe_server_list):

print('没有获取到要安装系统的主机')

SystemExit(1)

# dhcp

render = render_file(templateDir, template_list.get('dhcp'))

render.make(pxe_server_list, network)

render.export('dhcpd.conf', 'dhcp')

渲染后的结果

[root@localhost ~]# cat /etc/dhcp/dhcpd.conf 
default-lease-time 600;
max-lease-time 7200;

log-facility local7;

subnet 192.168.1.0 netmask 255.255.255.0 {
    range 192.168.1.100 192.168.1.200;
    option routers 192.168.1.1;
}


host 192.168.1.103 {
    hardware ethernet 22:44:FF:77:44:78;
    next-server 192.168.1.1;
    fixed-address 192.168.1.55;
    filename "RedHat.6.8/pxelinux.0";

}

host 192.168.1.132 {
    hardware ethernet 22:00:FF:EE:44:74;
    next-server 192.168.1.1;
    fixed-address 192.168.1.55;
    filename "CentOS.7.3/pxelinux.0";

}