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

For adding syslog support in PTL we will have to make changes in two files- log_utils.py and pbs_testlib.py

Changes in log_utils.py

Changes in this file are related to the format of the recorded datetime. Syslog records the datetime in a different format than local logs.

Some syslog files are compressed. Even if we can read a compressed file from python, but I would prefer if we decompress it so that rest of the code in PTL for reading files will work without any changes.

1) Check is file is compressed. Decompress it to same location with same name.

if sys_log_file == compressed

_sys_log_path_ = decompressed file

2) Date format.

Change regular expression ‘tm_re ’ to match the date format of the syslog file.

if PBS_SYSLOG=1 (in PBS.conf)

tm_re = "(?P<datetime>\w{3}\s\d\d\s\d\d:\d\d:\d\d)"

def convert_date_time()

if PBS_SYSLOG=1 (in PBS.conf)

Fmt of date = "%b %d %H:%M:%S"

t = time.strptime(datetime, fmt)

Changes in pbs_testlib.py

1) Change log_file path from local logs to syslog. The local log file are in 4 locations- server, mom, sched, comm. For syslog since there is only one file, we only have to point it to that file. Path to the log file can be set through a environment variable before starting the PTL tests or through the test script. If the path is not set the default path "/var/log/messages" will be taken

sys_log_file_path= syslog_path_

def init_logfile_path

if PBS_SYSLOG=1

path_log_file = _sys_log_path_

elif locally

path_log_file= __local_path__

Note- Def log_lines returns the last n lines of the log file.

def log_lines