1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
# Microsoft Azure Linux Agent
#
# Copyright 2014 Microsoft Corporation
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# Requires Python 2.4+ and Openssl 1.0+
#
import os
import socket
import time
import threading
import azurelinuxagent.common.conf as conf
import azurelinuxagent.common.logger as logger
from azurelinuxagent.common.dhcp import get_dhcp_handler
from azurelinuxagent.common.event import add_periodic, WALAEventOperation
from azurelinuxagent.common.osutil import get_osutil
from azurelinuxagent.common.protocol import get_protocol_util
from azurelinuxagent.common.version import AGENT_NAME, CURRENT_VERSION
def get_env_handler():
return EnvHandler()
class EnvHandler(object):
"""
Monitor changes to dhcp and hostname.
If dhcp clinet process re-start has occurred, reset routes, dhcp with fabric.
Monitor scsi disk.
If new scsi disk found, set timeout
"""
def __init__(self):
self.osutil = get_osutil()
self.dhcp_handler = get_dhcp_handler()
self.protocol_util = get_protocol_util()
self.stopped = True
self.hostname = None
self.dhcpid = None
self.server_thread = None
self.dhcp_warning_enabled = True
def run(self):
if not self.stopped:
logger.info("Stop existing env monitor service.")
self.stop()
self.stopped = False
logger.info("Start env monitor service.")
self.dhcp_handler.conf_routes()
self.hostname = self.osutil.get_hostname_record()
self.dhcpid = self.osutil.get_dhcp_pid()
self.server_thread = threading.Thread(target=self.monitor)
self.server_thread.setDaemon(True)
self.server_thread.start()
def monitor(self):
"""
Monitor firewall rules
Monitor dhcp client pid and hostname.
If dhcp clinet process re-start has occurred, reset routes.
"""
protocol = self.protocol_util.get_protocol()
while not self.stopped:
self.osutil.remove_rules_files()
if conf.enable_firewall():
success = self.osutil.enable_firewall(
dst_ip=protocol.endpoint,
uid=os.getuid())
add_periodic(
logger.EVERY_HOUR,
AGENT_NAME,
version=CURRENT_VERSION,
op=WALAEventOperation.Firewall,
is_success=success,
log_event=True)
timeout = conf.get_root_device_scsi_timeout()
if timeout is not None:
self.osutil.set_scsi_disks_timeout(timeout)
if conf.get_monitor_hostname():
self.handle_hostname_update()
self.handle_dhclient_restart()
time.sleep(5)
def handle_hostname_update(self):
curr_hostname = socket.gethostname()
if curr_hostname != self.hostname:
logger.info("EnvMonitor: Detected hostname change: {0} -> {1}",
self.hostname,
curr_hostname)
self.osutil.set_hostname(curr_hostname)
self.osutil.publish_hostname(curr_hostname)
self.hostname = curr_hostname
def handle_dhclient_restart(self):
if self.dhcpid is None:
if self.dhcp_warning_enabled:
logger.warn("Dhcp client is not running. ")
self.dhcpid = self.osutil.get_dhcp_pid()
# disable subsequent error logging
self.dhcp_warning_enabled = self.dhcpid is not None
return
#The dhcp process hasn't changed since last check
if self.osutil.check_pid_alive(self.dhcpid.strip()):
return
newpid = self.osutil.get_dhcp_pid()
if newpid is not None and newpid != self.dhcpid:
logger.info("EnvMonitor: Detected dhcp client restart. "
"Restoring routing table.")
self.dhcp_handler.conf_routes()
self.dhcpid = newpid
def stop(self):
"""
Stop server comminucation and join the thread to main thread.
"""
self.stopped = True
if self.server_thread is not None:
self.server_thread.join()
|
