Community discussion is present here: http://community.pbspro.org/t/pp-838-support-for-logging-via-syslog-in-pbs/591
Objective
PBS currently has a facility for logging via syslog. We are reverse engineering to the EDD. We need to have the use cases, test scenarios and test cases (both manual and PTL) reviewed by the open source community.
Use Cases
1. As an admin, I should be able to set PBS logging via syslog so that all daemons log into the same file.
2. As an admin, I should be able to control log events level of the PBS logging.
3. As an admin, I should be able to set the logging via syslog for all nodes in the cluster
4. As an admin, I should be able to set the logging via syslog for all servers in a failover environment.
5. As a admin I should be able to have logging into both local daemons and Syslog enabled together
6. As an admin/user, I should be able to run tracejob for a specific job with Syslog.
Note- This functionality is not currently given by PBS. This is added here because it is nice enhancement for future use.
7. As an admin/user, I should be able to differentiate log messages from each daemon.
8. As an admin/user, I should be able to set logging via syslog for only a particular daemon (Server, Mom, Sched or Comm).
Design
The design for adding syslog matching is been written so that there minimal changes for existing functionality. The same log_match() functions for each class (Server, MoM, Sched and Comm) are been used with changes to read into syslog. For example to check server messages that go into syslog we will have the same method server.log_match(). This will also help the tests differentiate the messages from individual daemons.
PTL will read into syslog in these cases-
1) syslog parameter is set in log_match() function
2) PBS_SYSLOG is set in pbs.conf. This case is for running the existing PTL tests which do not have syslog parameter in log_match().
We should make sure that the user running the tests will have permissions to read syslog file and decompress it. For eg - in test bed machine pbsroot shoud be able to read from syslog file.
For adding syslog support in PTL we will have to make changes in two files- pbs_logutils.py and pbs_testlib.py.
A new class syslog_utils is added for reading the date, syslog file path and the logic for which log messages file to check.
———————syslog_utils.py——————
To add the functionality on which logs to check in log_match(), syslog or local logs we will follow this table -
PBS_SYSLOG and PBS_LOCALLOG are values from the pbs.conf file. Syslog_attribute is the attribute to be passed to the log_match() function. Return value is the return value of log_match()
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In row 7 where we have to match in both syslog and local log, we would have to call _log_match() twice.
import platform
class syslog_utils(object):
du = DSHUtils()
# Syslog conf file data path
syslog_conf_path = {'rsyslogd': '/etc/rsyslog.conf', 'syslog-ng': '/etc/syslog-ng/syslog-ng.conf'}
# PBS supported severity and facilities
p_severity = ['info', 'debug']
p_facility = ['*', 'local7', ....]
def log_config_values(syslog=0)
// logic for which file to read will come from the above table
// returns a integer value which is interpreted as which file to check
file_to_check=0
// read from PBS.conf PBS_SYSLOG & PBS_LOCALLOG
// Logic of which file to read log messages from- syslog / local
// file_to_check =1 for syslog, file_to_check=2 for local, file_to_check=3 for both
return file_to_check
def log_syslog_lines(self):
//This function returns the syslog messages for logmatch
# get syslog utility running and conf file
self.cmd_sys = "ps -e | grep syslog | awk '{print $NF}'"
self.utility = self.du.run_cmd(hosts=hostname, cmd=self.cmd_sys, as_script=True, sudo=True,
level=logging.DEBUG2)['out']
self.syslog_conf_file = self.syslog_conf_path.get(self.utility[0])
#get syslog log files to be read.
list_of_priority = []
if self.utility[0] == "rsyslogd":
list_of_priorities = self.get_rsyslog_priorites()
self.list_of_syslog_files = self.get_rsyslog_files(list_of_priorities)
elif self.utility[0] == "syslog-ng":
list_of_priorities = self.get_syslogng_priorites()
self.list_of_syslog_files = self.get_syslogng_files(list_of_priorities)
else:
// throw error
// PtlLogMatchError(rc=1, rv=False, msg=_msg)
# Get lines from each of the files from list_of_syslog_files[]
lines = []
combined_lines = []
for x in self.list_of_syslog_files:
l_sys = self.get_syslog_lines(hostname=hostname, n=n, filename=x, logval=logval)
lines.append(l_sys)
# combine lines from each file
combined_lines = [item for sublist in lines for item in sublist]
# Sort lines by datetime
combined_lines.sort(key=lambda x: datetime.datetime.strptime(x[:15], "%b %d %H:%M:%S"))
return combined_lines
def get_rsyslog_priorites(self, severity=None, facility=None)
# Returns the priorities. Since the syslog messages can be stored in multiple files, a list is returned
# If facility and severity mentioned return the file for that combination from rsyslog.conf
# If severity and facility is NONE read into rsyslog.conf file and return all files that contain the severity set in syslog-ng.conf
return list_of_priorities[]
def get_syslogng_priorites(self, severity=None, facility=None)
# Returns the priorities. Since the syslog messages can be stored in multiple files, a list is returned
# If facility and severity mentioned return the file for that combination from rsyslog.conf
# If severity and facility is NONE read into rsyslog.conf file and return all files that contain the severity set in syslog-ng.conf
return list_of_priorities[]
def get_rsyslog_files(self, list_of_priorities)
# Returns the files to be read. Since the syslog messages can be stored in multiple files, a list is returned
# If facility and severity mentioned return the file for that combination from rsyslog.conf
# If severity and facility is NONE read into rsyslog.conf file and return all files that contain the severity set in rsyslogd.conf
return list_of_files[]
def get_syslog_ng_files(self, list_of_priorities)
# Returns the files to be read. Since the syslog messages can be stored in multiple files, a list is returned
# If facility and severity mentioned return the file for that combination from syslog-ng.conf
# If severity and facility is NONE read into rsyslog.conf file and return all files that contain the severity set in syslog-ng.conf
return list_of_files[]
def get_syslog_lines(self, hostname=None, n=50, filename=None, logval=None):
# Return sthe last block of lines from the syslog files for that particular daemon
# n= number of lines requested by user
#hostname = host from which to read syslog file
# file name is the file to read
# is user says all lines, default to 100
if n == "ALL":
n=100
# if hostname is None, default to machine on which ptl is running
if hostname is None:
hostname = socket.gethostname()
if logval is 'sched_logs':
daemon_str = 'pbs_sched'
elif logval is 'server_logs':
daemon_str = 'Server@'
elif logval is 'mom_logs':
daemon_str = 'pbs_mom'
elif logval is 'comm_logs':
daemon_str = 'pbs_comm'
else:
// PtlLogMatchError(rc=1, rv=False, msg=_msg)
# use tail command to get last block of lines from file
cmd = ['/usr/bin/tail']
cmd += [str(n), filename]
lines = self.du.run_cmd(hosts=hostname, cmd=cmd, sudo=True,
level=logging.DEBUG2)['out']
lines = [l for l in lines if daemon_str in l]
return lines
————pbs_testlib.py——————————
Following changes are done to the current log_match() function
1) Adding extra attribute 'syslog' to _log_match(syslog=False)
By default this attribute should be set to false
This syslog attribute will also be passed on to further functions from log_match- def _log_match(syslog=false), init_logfile_path(syslog=False), def log_lines(syslog=False)
log_match() calls the _log_match() method.
Therefore according to the table above we should have a conditional statements in log_match()
In case both have to be read we should call the _log_match() twice.
class PBSService(PBSObject)
def log_match(syslog=False)
// Additions: Get the value of whether to read syslog or locallog files
if syslog:
x= syslog_config.log_config_values(syslog=true)
// Values to pass to _log_match()
if x==1
return _log_match(syslog=true)
elif x==2
return _log_match(syslog=false)
elif x==3
syslog_return = _log_match(syslog=true)
// Read in local logs only if syslog log match is returned true. If syslog fails there is no need to check in local logs
if syslog_return:
return _log_match(syslog=false)
else:
return syslog_return
else:
_msg= "Log file to check not set"
PtlLogMatchError(rc=1, rv=False, msg=_msg)
def _log_match(syslog=False)
lines = self.log_lines(syslog=true)
rv = self.logutils.match_msg(syslog=true)
Note- 'def log_lines' returns the last n lines of the log file.
def log_lines(syslog=False)
logval = None
lines = None
sudo = False
self.syslogUtils = syslog_utils()
if syslog:
logval = self._instance_to_logpath(logtype)
lines = self.syslogUtils.log_syslog_lines(hostname=self.hostname, n=n, logval=logval)
——————————In pbs_logutils.py—————————————
Currently we are only supporting for the current syslog file and not for previous days file. That would be covered in PP-969
Class PBSLogUtils(object)
def convert_date_time(syslog=false)
if syslog:
fmt="%b %d %H:%M:%S"
try:
t = time.strptime(datetime, fmt)
if syslog:
now = time.strftime("%Y,%m,%d,%H,%M,%S")
split_now = now.split(',')
t_edit = list(t)
t_edit[0]= int(split_now[0])
t = time.struct_time(tuple(t_edit))
def match_msg(syslog=false)
if syslog:
date_length = //length according to date format (by default set to 15)
if lines:
for l in lines:
if starttime is not None:
tm = self.convert_date_time(l[:date_length], syslog_flag=syslog)
if endtime is not None:
tm = self.convert_date_time(l[:date_length], syslog_flag=syslog)
Test Scenarios
1) Test that when PBS_SYSLOG=1 is enabled in pbs.conf, PBS logs messages via syslog.
2) Test that according to the PBS_SYSLOGSEVR value in pbs.conf the messages of that severity are logged via syslog. This should include tests for each severity level- Emergency, alert , critical, error, warning, notice, informational, debug.
3) Test that in a multi-node cluster setup, logging via syslog can be enabled.
4) Test that in a failover environment logging via syslog works on all the servers.
5) Test that both local logging and logging via syslog can be enabled simultaneously for both, single node and execution nodes in a cluster.
6) Test that tracejob works when logging via syslog is enabled
(Note: trace job currently does not work with Syslog. Since this is a use case and would be a nice enhancement to have)
7) Test that server and sched and mom messages can be differentiated explicitly in the syslog log file.
8) Test that logging via sys logging can be set for only a particular daemon.