diff options
Diffstat (limited to 'azurelinuxagent/ga/env.py')
| -rw-r--r-- | azurelinuxagent/ga/env.py | 147 |
1 files changed, 116 insertions, 31 deletions
diff --git a/azurelinuxagent/ga/env.py b/azurelinuxagent/ga/env.py index 45b10bb..d9b7d82 100644 --- a/azurelinuxagent/ga/env.py +++ b/azurelinuxagent/ga/env.py @@ -17,11 +17,16 @@ # Requires Python 2.4+ and Openssl 1.0+ # +import re import os import socket import time import threading +import operator + +import datetime + import azurelinuxagent.common.conf as conf import azurelinuxagent.common.logger as logger @@ -29,15 +34,29 @@ 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.protocol.wire import INCARNATION_FILE_NAME +from azurelinuxagent.common.utils import fileutil from azurelinuxagent.common.version import AGENT_NAME, CURRENT_VERSION +CACHE_PATTERNS = [ + re.compile("^(.*)\.(\d+)\.(agentsManifest)$", re.IGNORECASE), + re.compile("^(.*)\.(\d+)\.(manifest\.xml)$", re.IGNORECASE), + re.compile("^(.*)\.(\d+)\.(xml)$", re.IGNORECASE) +] + +MAXIMUM_CACHED_FILES = 50 + +CACHE_PURGE_INTERVAL = datetime.timedelta(hours=24) + + 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. + If dhcp client process re-start has occurred, reset routes, dhcp with fabric. Monitor scsi disk. If new scsi disk found, set timeout @@ -48,9 +67,10 @@ class EnvHandler(object): self.protocol_util = get_protocol_util() self.stopped = True self.hostname = None - self.dhcpid = None + self.dhcp_id = None self.server_thread = None self.dhcp_warning_enabled = True + self.last_purge = None def run(self): if not self.stopped: @@ -61,7 +81,7 @@ class EnvHandler(object): 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.dhcp_id = self.osutil.get_dhcp_pid() self.server_thread = threading.Thread(target=self.monitor) self.server_thread.setDaemon(True) self.server_thread.start() @@ -70,26 +90,24 @@ class EnvHandler(object): """ Monitor firewall rules Monitor dhcp client pid and hostname. - If dhcp clinet process re-start has occurred, reset routes. + If dhcp client process re-start has occurred, reset routes. + Purge unnecessary files from disk cache. """ protocol = self.protocol_util.get_protocol() while not self.stopped: self.osutil.remove_rules_files() - # Disable setting firewall for now, regardless of configuration switch - # 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) - - self.osutil.remove_firewall() + 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=False) timeout = conf.get_root_device_scsi_timeout() if timeout is not None: @@ -100,6 +118,8 @@ class EnvHandler(object): self.handle_dhclient_restart() + self.purge_disk_cache() + time.sleep(5) def handle_hostname_update(self): @@ -113,30 +133,95 @@ class EnvHandler(object): self.hostname = curr_hostname def handle_dhclient_restart(self): - if self.dhcpid is None: + if self.dhcp_id is None: if self.dhcp_warning_enabled: logger.warn("Dhcp client is not running. ") - self.dhcpid = self.osutil.get_dhcp_pid() + self.dhcp_id = self.osutil.get_dhcp_pid() # disable subsequent error logging - self.dhcp_warning_enabled = self.dhcpid is not None + self.dhcp_warning_enabled = self.dhcp_id is not None + return + + # the dhcp process has not changed since the last check + if self.osutil.check_pid_alive(self.dhcp_id.strip()): return - #The dhcp process hasn't changed since last check - if self.osutil.check_pid_alive(self.dhcpid.strip()): + new_pid = self.osutil.get_dhcp_pid() + if new_pid is not None and new_pid != self.dhcp_id: + logger.info("EnvMonitor: Detected dhcp client restart. " + "Restoring routing table.") + self.dhcp_handler.conf_routes() + self.dhcp_id = new_pid + + def purge_disk_cache(self): + """ + Ensure the number of cached files does not exceed a maximum count. + Purge only once per interval, and never delete files related to the + current incarnation. + """ + if self.last_purge is not None \ + and datetime.datetime.utcnow() < \ + self.last_purge + CACHE_PURGE_INTERVAL: + return + + current_incarnation = -1 + self.last_purge = datetime.datetime.utcnow() + incarnation_file = os.path.join(conf.get_lib_dir(), + INCARNATION_FILE_NAME) + if os.path.exists(incarnation_file): + last_incarnation = fileutil.read_file(incarnation_file) + if last_incarnation is not None: + current_incarnation = int(last_incarnation) + + logger.info("Purging disk cache, current incarnation is {0}" + .format('not found' + if current_incarnation == -1 + else current_incarnation)) + + # Create tuples: (prefix, suffix, incarnation, name, file_modified) + files = [] + for f in os.listdir(conf.get_lib_dir()): + full_path = os.path.join(conf.get_lib_dir(), f) + for pattern in CACHE_PATTERNS: + m = pattern.match(f) + if m is not None: + prefix = m.group(1) + suffix = m.group(3) + incarnation = int(m.group(2)) + file_modified = os.path.getmtime(full_path) + t = (prefix, suffix, incarnation, f, file_modified) + files.append(t) + break + + if len(files) <= 0: 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 + # Sort by (prefix, suffix, file_modified) in reverse order + files = sorted(files, key=operator.itemgetter(0, 1, 4), reverse=True) + + # Remove any files in excess of the maximum allowed + # -- Restart then whenever the (prefix, suffix) change + count = 0 + last_match = [None, None] + for f in files: + if last_match != f[0:2]: + last_match = f[0:2] + count = 0 + + if current_incarnation == f[2]: + logger.verbose("Skipping {0}".format(f[3])) + continue + + count += 1 + + if count > MAXIMUM_CACHED_FILES: + full_name = os.path.join(conf.get_lib_dir(), f[3]) + logger.verbose("Deleting {0}".format(full_name)) + os.remove(full_name) def stop(self): """ - Stop server comminucation and join the thread to main thread. + Stop server communication and join the thread to main thread. """ self.stopped = True if self.server_thread is not None: self.server_thread.join() - |