python运维实战--LVM创建和在线扩容
LVM有关概念和操作
说明⚠️：有关LVM详细概念，请各位大佬自行百度，谷歌。。这里不做重点介绍。
这个python脚本能做什么
创建LVM
- 指定具体磁盘进行分区，这里定义分区号1
- 刷新分区，不需要reboot系统
- 创建pv
- 创建vg
- 创建lv
- 格式化，ext4/xfs
- 创建挂载目录
- 将文件系统信息写到 /etc/fstab
- 使用 mount -a 自动挂载
在线扩容vg／lv
- 磁盘分区
- 刷新分区信息
- 创建pv
- 在线扩容vg
- 在线扩容lv
- 扩容后容量刷新
python 脚本信息
#!/usr/bin/env python
# coding=utf-8
__author__ = "wutf"
__email__ = "wutf@data.com"
__status__ = "Production"
__version__ = "1.0"
from optparse import OptionParser
from subprocess import Popen, call, PIPE
from shlex import split
from commands import getstatusoutput
from os import mkdir
from os.path import basename , normpath
import time
parser = OptionParser()
parser.add_option('-d', '--drive', dest='drive', help='this is the name of the drive like sda, hdd etc..')
parser.add_option('-f', '--folder', dest='folder', help='this is the name of the directory like /data or /var/log')
parser.add_option('-t', '--fstype', dest='fstype', help='this is the type of filesystem you need like ext4 or xfs')
(opts,args) = parser.parse_args()
class FormatDriver(object):
"""
This is a class that does end to end create partition, deal with lvm, make filesystem, extend filesystem, write to fstab and resize filesystem
"""
def __init__(self,drive,folder,fstype):
self.drive = str(drive)
self.folder = str(folder)
self.fstype = str(fstype)
def fdisk(self):
"""
this is a definition to perform fdisk the drive in the argument
"""
before_pipe_cmd = 'echo -e "n\np\n1\n\n\nt\\n8e\nw"'
before_pipe_args = split(before_pipe_cmd)
after_pipe_cmd = "fdisk /dev/%s" % self.drive
after_pipe_args = split(after_pipe_cmd)
p1 = Popen(before_pipe_args, stdout=PIPE)
p2 = call(after_pipe_args, stdin=p1.stdout)
def partprobe(self):
"""
this function performs the partprobe
"""
pprobe = "partprobe"
pprobe1 = split(pprobe)
part = call(pprobe1)
def pvcreate(self):
"""
This function creates the physical volume
"""
pvcreate = call(["pvcreate", "/dev/%s1" %self.drive])
def volgroup(self):
"""
This function creates the physical volume and also created the volume group
"""
vgcreate = 'vgcreate -v vg_%s /dev/%s1' % (basename(normpath(self.folder)), self.drive)
status, output = getstatusoutput(vgcreate)
def lvm(self):
"""
This function creates the logical volume
"""
lvcreate = 'lvcreate -v -l "100%FREE" -n lv_{0} vg_{1}'.format(basename(normpath(self.folder)),
basename(normpath(self.folder)))
status, output = getstatusoutput(lvcreate)
print status
print output
def makefs(self):
'''This functions creates the filesystem on the /dev/mapper LVM device'''
if self.fstype == 'ext4':
mkfs = call(["mkfs.ext4", "/dev/mapper/vg_%s-lv_%s" % (
basename(normpath(self.folder)), basename(normpath(self.folder)))])
elif self.fstype == 'xfs':
mkfs = call(["mkfs.xfs", "/dev/mapper/vg_%s-lv_%s" % (
basename(normpath(self.folder)), basename(normpath(self.folder)))])
def makedir(self):
'''This function makes directory inthe /root level'''
path = "%s" % self.folder
mkdir(path, 0755)
print '%s is created' % path
def write_to_fstab(self):
'''This function appends the filesystem info to the /etc/fstab'''
if self.fstype == 'ext4':
string = '/dev/mapper/vg_%s-lv_%s %s ext4 defaults 1 1' % (
basename(normpath(self.folder)), basename(normpath(self.folder)), self.folder)
f = open("/etc/fstab", 'a')
f.write(string + "\n")
f.close()
elif self.fstype == 'xfs':
string = '/dev/mapper/vg_%s-lv_%s %s xfs defaults 1 1' % (
basename(normpath(self.folder)), basename(normpath(self.folder)), self.folder)
f = open("/etc/fstab", 'a')
f.write(string + "\n")
f.close()
def filesystem_mount(self):
'''This is a simple function to mount all the drive'''
fsmount = 'mount -a'
status, output = getstatusoutput(fsmount)
def resizefs(self):
''' This method is to resize an existing filesystem'''
if self.fstype == 'ext4':
rs = 'resize2fs /dev/vg_%s/lv_%s' % (basename(normpath(self.folder)), basename(normpath(self.folder)))
status, output = getstatusoutput(rs)
elif self.fstype == 'xfs':
rs = 'xfs_growfs /dev/vg_%s/lv_%s' % (basename(normpath(self.folder)), basename(normpath(self.folder)))
status, output = getstatusoutput(rs)
def extend_vg(self):
'''Extending volume group'''
vgextend = 'vgextend vg_%s /dev/%s1' % (basename(normpath(self.folder)), self.drive)
status, output = getstatusoutput(vgextend)
def extend_lv(self):
'''Extending logical volume'''
lvextend = call(["lvextend", "-l", "+100%FREE",
"/dev/vg_%s/lv_%s" % (basename(normpath(self.folder)), basename(normpath(self.folder)))])
def main():
x = FormatDriver(opts.drive, opts.folder, opts.fstype)
intake = raw_input("Do you want to extend of create a new filesystem ? please enter 'extend' or 'create':")
if intake == 'create':
print "a new drive has been created"
x.fdisk()
x.partprobe()
x.pvcreate()
time.sleep(5)
x.volgroup()
time.sleep(5)
x.lvm()
x.makefs()
x.makedir()
x.write_to_fstab()
x.filesystem_mount()
elif intake == 'extend':
print "a drive has been extended"
x.fdisk()
x.partprobe()
x.pvcreate()
x.extend_vg()
x.extend_lv()
x.resizefs()
if __name__ == '__main__':
if opts.drive == None or opts.folder == None or opts.fstype == None:
parser.print_help()
exit(-1)
main()
print 'The root folder is %s' % opts.folder
print 'the drive is %s' % opts.drive
print 'The fstype is %s' % opts.fstype
说明⚠️：
- popen 类的作用是获取用户启动的应用程序进程信息，以便跟踪程序进程的运行状态。
脚本执行情况
实战创建LVM
# python test.py -d sdb -f /data1 -t ext4
Do you want to extend of create a new filesystem ? please enter 'extend' or 'create':create
a new drive has been created
欢迎使用 fdisk (util-linux 2.23.2)。
....
/data1 is created
The root folder is /data1
the drive is sdb
The fstype is ext4
说明⚠️：如果执行脚本时不使用任何参数，则会提示帮助信息，如：
# python test.py
Usage: test.py [options]
Options:
-h, --help show this help message and exit
-d DRIVE, --drive=DRIVE
this is the name of the drive like sda, hdd etc..
-f FOLDER, --folder=FOLDER
this is the name of the directory like /data or
/var/log
-t FSTYPE, --fstype=FSTYPE
this is the type of filesystem you need like ext4 or
xfs