dominfo.py

Libvirt是一套在linux上用C编写的虚拟化操作工具接口。其目的是提供一个稳定的支持Xen

#! /usr/bin/python
# dominfo - print some information about a domain

import libvirt
import sys
import os
import libxml2
import pdb

def usage():
   print 'Usage: %s DOMAIN' % sys.argv[0]
   print '       Print information about the domain DOMAIN'

def print_section(title):
    print "\n%s" % title
    print "=" * 60

def print_entry(key, value):
    print "%-10s %-10s" % (key, value)

def print_xml(key, ctx, path):
    res = ctx.xpathEval(path)
    if res is None or len(res) == 0:
        value="Unknown"
    else:
        value = res[0].content
    print_entry(key, value)
    return value
    
if not os.access("/proc/xen", os.R_OK):
    print 'System is not running a Xen kernel'
    sys.exit(1)

if len(sys.argv) != 2:
    usage()
    sys.exit(2)

name = sys.argv[1]

# Connect to libvirt
conn = libvirt.openReadOnly(None)
if conn == None:
    print 'Failed to open connection to the hypervisor'
    sys.exit(1)

try:
    dom = conn.lookupByName(name)
    # Annoyiingly, libvirt prints its own error message here
except libvirt.libvirtError:
    print "Domain %s is not runing" % name
    sys.exit(0)

info = dom.info()
print_section("Domain info")
print_entry("State:", info[0])
print_entry("MaxMem:", info[1])
print_entry("UsedMem:", info[2])
print_entry("VCPUs:", info[3])

# Read some info from the XML desc
xmldesc = dom.XMLDesc(0)
doc = libxml2.parseDoc(xmldesc)
ctx = doc.xpathNewContext()
print_section("Kernel")
print_xml("Type:", ctx, "/domain/os/type")
print_xml("Kernel:", ctx, "/domain/os/kernel")
print_xml("initrd:", ctx, "/domain/os/initrd")
print_xml("cmdline:", ctx, "/domain/os/cmdline")

print_section("Devices")
devs = ctx.xpathEval("/domain/devices/*")
for d in devs:
    ctx.setContextNode(d)
    #pdb.set_trace()
    type = print_xml("Type:", ctx, "@type")
    if type == "file":
        print_xml("Source:", ctx, "source/@file")
        print_xml("Target:", ctx, "target/@dev")
    elif type == "block":
        print_xml("Source:", ctx, "source/@dev")
        print_xml("Target:", ctx, "target/@dev")
    elif type == "bridge":
        print_xml("Source:", ctx, "source/@bridge")
        print_xml("MAC Addr:", ctx, "mac/@address")