This article talks about the log files available in Recital products and how to enable logging when required.
Overview
When discussing a problem with the Recital Support Team, one of the most common requests is that you enable logging and send them the log files produced. Log files along with error files are designed to provide detailed information about Recital processes and the prevailing environment and can be a fast-track to resolving a problem.
Log Files
There are three main types of log file:
- System Log
- Client/Server Communication Logs
- Custom Logs
System Log
The System log is a system-wide all product log. It tracks all login and logout operations from either Recital or the Recital Server. Logout details include the exit code: 0 for an error-free, 'normal' exit and the error number and message when an error has occurred. It also shows the licenses that have been loaded and any license error codes and messages. The system log filename is recital.log.
Client/Server Communication Logs
The Client/Server communication logs track the requests and responses between the Recital Server and its clients. The log files are as follows:
| Filename | Type | Description |
|---|---|---|
|
dbserver.log |
System-wide |
The Recital Server startup log. This logs any problems with the Recital Server startup. |
|
port.log |
System-wide |
The port listener log. The port listener (or portserver) listens on port 8001 for client connection requests and spawns the appropriate server process. |
|
net.log |
Connection |
The netserver log. The netserver is the Recital Server database and 4GL engine. |
|
rsi.log |
Connection |
The Recital Server Interface (RSI) Gateway log. This logs communication with the Database Gateways to SQL databases. |
|
rec.log |
Connection |
The Recital Database Gateway log. The Recital Database Gateway (or recserver) is the SQL database engine for Recital Gateway data access. |
|
mys.log |
Connection |
The MySQL Database Gateway log. |
|
ora.log |
Connection |
The Oracle Database Gateway log. |
|
inf.log |
Connection |
The Informix Database Gateway log. |
|
ing.log |
Connection |
The Ingres Database Gateway log. |
|
pos.log |
Connection |
The PostgreSQL Database Gateway log. |
|
jdb.log |
Connection |
The JDBC Driver Database Gateway log. |
Custom Logs
The Recital/4GL USERLOG() function can be used to log information to a user-specific log file for debugging or audit trail purposes. For full information on this function, please see the USERLOG() documentation.
Enabling Log Files
For instructions on enabling log files for individual products, please follow these links:
- Recital Server for Windows
- Recital Server for Linux
- Recital Server for UNIX
- Recital Server for OpenVMS
- Recital for Linux
- Recital for UNIX
- Recital for OpenVMS
Enabling Log Files: Recital Server for Windows
To enable the system log file for the Recital Universal Application Server for Windows, include the following command in the UAS\config.db file:
set syslogging on
The Recital Server Manager System Logging tab allows for the viewing and resetting of the System log.
Section
Item
Description
System Logging
DateTime
Date and time stamp of the action.
Name
Login name used by connection
Action
Action logged: Login, Logoff, Errot
Details
Details of action
Buttons
Purge
Allows the log file to be reset
Refresh
Refreshes the display
To set up Client/Server logging, use the Recital Server Manager Settings tab to update the server's Registry entries:
The following Log file settings can be configured:
|
Item |
Description |
|---|---|
|
Log files Directory Path |
Enter the directory in which log files will be created. The default is the UAS\log directory. |
|
Enabled |
Check to enable log file creation. |
|
Versions |
Check to enable log file versioning. |
|
Listener |
Click to view the current port listener log file |
|
Server |
Click to view the current netserver log file |
|
Purge |
Click to purge all log files |
Enabling Log Files: Recital Server for Linux
To enable the system log file for the Recital Server for Linux, include the following command in the conf/config.db file:
set syslogging on
To set up Client/Server logging, the Recital Server can be started with the 'logging' parameter, in which case, all relevant logging will take place.
# service startup logging<
Alternatively, one or more of the following environment variables can be added to the dbserver.conf file or set at the Operating System prompt. The Recital Server must be restarted before environment variable changes will be recognized. Each environment variable should be set to the name of a log file.
Environment Variable
Logs Activity of...
UASLOG_PORT
Port Server (db_rsiserver)
UASLOG_NET
(Net) Server (db_netserver)
UASLOG_ORA
Oracle Server (db_oraserver)
UASLOG_INF
Informix Server (db_infserver)
UASLOG_ING
Ingres Server (db_ingserver)
UASLOG_JDB
JDBC Server (db_jdbserver)
UASLOG_REC
Recital Server (db_recserver)
Extract from recital.conf:
UASLOG_PORT="port.log" ; export UASLOG_PORT UASLOG_NET="net.log" ; export UASLOG_NET UASLOG_ORA="ora.log" ; export UASLOG_ORA UASLOG_INF="inf.log" ; export UASLOG_INF UASLOG_ING="ing.log" ; export UASLOG_ING UASLOG_JDB="jdb.log" ; export UASLOG_JDB UASLOG_REC="rec.log" ; export UASLOG_REC
DB_LOGDIR
If the environment variable DB_LOGDIR is set to an existing directory, all log files will be written to this directory. If not, the log files will be created in the bin directory.
DB_LOGDIR is set in the conf/recital.conf file. By default it is set to the log directory:
DB_LOGDIR=${ROI_ROOT}log/ ; export DB_LOGDIR
DB_LOGVER
If the environment variable DB_LOGVER is greater than 0, version numbers are added to the file names. For example, the activity of the first Net Server process will be logged to net.log, the second to net001.log, the third to net002.log etc. up to the maximum value of DB_LOGVER.
DB_LOGVER is set in the conf/recital.conf file:
DB_LOGVER=10; export DB_LOGVER
Enabling Log Files: Recital Server for UNIX
To enable the system log file for the Recital Server for UNIX, include the following command in the conf/config.db file:
set syslogging on
To set up Client/Server logging, the Recital Server can be started with the 'logging' parameter, in which case, all relevant logging will take place.
# service startup logging
Alternatively, one or more of the following environment variables can be added to the <em>dbserver.conf</em> file or set at the Operating System prompt. The Recital Server must be restarted before environment variable changes will be recognized. Each environment variable should be set to the name of a log file.
Environment Variable
Logs Activity of...
UASLOG_PORT
Port Server (db_rsiserver)
UASLOG_NET
(Net) Server (db_netserver)
UASLOG_ORA
Oracle Server (db_oraserver)
UASLOG_INF
Informix Server (db_infserver)
UASLOG_ING
Ingres Server (db_ingserver)
UASLOG_JDB
JDBC Server (db_jdbserver)
UASLOG_REC
Recital Server (db_recserver)
Extract from recital.conf:
UASLOG_PORT="port.log" ; export UASLOG_PORT UASLOG_NET="net.log" ; export UASLOG_NET UASLOG_ORA="ora.log" ; export UASLOG_ORA UASLOG_INF="inf.log" ; export UASLOG_INF UASLOG_ING="ing.log" ; export UASLOG_ING UASLOG_JDB="jdb.log" ; export UASLOG_JDB UASLOG_REC="rec.log" ; export UASLOG_REC
DB_LOGDIR
If the environment variable DB_LOGDIR is set to an existing directory, all log files will be written to this directory. If not, the log files will be created in the bin directory.
DB_LOGDIR is set in the conf/recital.conf file. By default it is set to the log directory:
DB_LOGDIR=${DB_ROOT}log/ ; export DB_LOGDIR
DB_LOGVER
If the environment variable DB_LOGVER is greater than 0, version numbers are added to the file names. For example, the activity of the first Net Server process will be logged to net.log, the second to net001.log, the third to net002.log etc. up to the maximum value of DB_LOGVER.
DB_LOGVER is set in the conf/recital.conf file:
DB_LOGVER=10; export DB_LOGVER
Enabling Log Files: Recital Universal Application Server for OpenVMS
To enable the system log file for the Recital Universal Application Server for OpenVMS, include the following command in the db_uas:config.db file:
set syslogging on
To set up Client/Server logging, one or more of the following symbols can be added to the <em>db_uas:login.com</em> file. The Recital Server must be restarted before symbol changes will be recognized. Each symbol should be set to the name of a log file.
Symbol
Logs Activity of…
UASLOG_PORT
Port Server (db_rsiserver)
UASLOG_NET
(Net) Server (db_netserver)
UASLOG_ORA
Oracle Server (db_oraserver)
UASLOG_INF
Informix Server (db_infserver)
UASLOG_ING
Ingres Server (db_ingserver)
UASLOG_JDB
JDBC Server (db_jdbserver)
UASLOG_REC
Recital Server (db_recserver)
Extract from db_uas:login.com
$ uaslog_port :== port.log $ uaslog_net :== net.log $ uaslog_ora :== ora.log $ uaslog_inf :== inf.log $ uaslog_ing :== ing.log $ uaslog_jdb :== jdb.log $ uaslog_rec :== rec.log
DB_LOGDIR
If the symbol DB_LOGDIR is set to an existing directory, all log files will be written to this directory. If not, the log files will be created in the UAS directory.
DB_LOGDIR is set in the db_uas:login.com file. By default it is set to the UAS.log] directory:
$db_logdir :== 'db_root'.log] ! system logging directory
DB_LOGVER
If the symbol DB_LOGVER is enabled, version numbers are added to the file names. For example, the activity of the first Net Server process will be logged to net.log, the second to net001.log, the third to net002.log etc.
DB_LOGVER is set in the db_uas:login.com file:
$db_logver :== true ! enable multiple log files
Enabling Log Files: Recital for Linux
To enable the system log file for Recital for Linux, include the following command in the conf/config.db file:
set syslogging on
Enabling Log Files: Recital for UNIX
To enable the system log file for Recital for UNIX, include the following command in the conf/config.db file:
set syslogging on
Enabling Log Files: Recital for OpenVMS
To enable the system log file for Recital for OpenVMS, include the following command in the db_ovd:config.db file:
set syslogging on
In Brief
- Log files provide important information to aid problem resolution, but they are also an overhead, so logging should only be enabled when required, not in normal production operation.
- The System log provides a system-wide view of logins, exits and error codes.
- The System log can be viewed in table format via the SYSLOGGING System Table.
- The System log is enabled using the SET SYSLOGGING ON Recital/4GL command in the conf/config.db file.
- Client/Server logs provide detailed information on client/server requests and responses.
- Client/Server logs are enabled using environment variables, symbols or Registry entries or by specifying the 'logging' parameter when starting the Recital Server.
- The location of log files is determined by the DB_LOGDIR setting.
- Versioning of log files is determined by the DB_LOGVER setting.
Ext3 commits writes to disk within approximately 5 seconds - Ext4 can take from 40-150 seconds. In addition, if a system is using Ext3 and crashes before the commit takes place you will still have the previous contents of a file where under Ext4 the file will be empty. Theodore Tso feels that this is a failure at the application level and that the file system is behaving as designed and as specified by the POSIX spec (which apparently does not specify what is supposed to happen when a system is not shut down cleanly). His solution to the issue is to suggest proper use of fsync() and lists various scenarios/examples in post 54 of the bug report (linked above). In addition he wrote a patch that recognize the rename() situation mentioned in his post 54 yet retains the normal Ext4 behaviors and performance in the majority of cases. Also a more "proper" solution has been provided which allows the behavior of Ext3 to be retained under Ext4 by mounting it with alloc_on_commit.
A somewhat related topic is the use of on-board caching by hard drives. This behavior can be modified on most drives by using hdparm.
SE Linux is a feature of the Linux kernel that provides mandatory access control. This policy based access control system grants far greater control over the resources on a machine than standard Linux access controls such as permissions.
Many modern Linux distributions are shipping with SELinux enabled by default, Fedora 14 and Rhel 6 both install with it enabled.
When you run Recital Web on a SELinux enabled machine and navigate to the default.rsp page you will see something similar to the screen shot below.
If you launch the SELinux troubleshooter you will see the following problem.
SELinux is blocking the apache server from accessing the Recital server running on port 8001.
To manage you SELinux policy you must have the policycoreutils package group installed. The policycoreutils contains the policy core utilities that are required for basic operation of a SELinux system.
If you wish to use a GUI tool, you must install the policycoreutils-gui package.
At the command prompt execute the following:
As root
$ yum install policycoreutils
$ semanage port -a -t http_port_t -p tcp 8001
$ service recital restart
$ service httpd restart
We use the semanage command here to allow the http server access to port 8001. Once you have completed the steps detailed above you can go and navigate back to the default.rsp page in your borwser, where you will find the permission denied message is now replaced by the default.rsp page.
SELinux does a great job of restricting services and daemons so rather than simply disabling it, why not work with it!
When it comes to security, every little bit helps...
System Requirements:
- Minimum memory: 4MB
- Minimum Diskspace: ~20MB
MQCURMSGS()
Syntax
MQCURMSGS( <expN> )Description
The MQCURMSGS() function returns the current number of unread messages in the queue specified by <expN>Example
mqdes=mqopen("/myqueue")
if (mqdes < 0)
messagebox(strerror()+",errno="+alltrim(str(error())))
return
endif
do while (mqcurmsgs(mqdes) > 0)
mstr=mqreceive(mqdes)
if (empty(mstr))
messagebox(strerror()+",errno="+alltrim(str(error())))
return
endif
messagebox(mstr)
end do
mqclose(mqdes)
Some options of hdparm are dangerous and are generally listed as such in the man page.
Hdparm is available from SourceForge and there is even a version for Windows.
STRERROR()
Syntax
STRERROR( [ <expN> ] )Description
The STRERROR() function returns a string describing the last operating system error message. If the optional error number is specified then the related operating system error message will be returned.Example
mqdes=mqcreate("/myqueue", 2)
if (mqdes < 0)
messagebox(strerror()+",errno="+alltrim(str(error())))
return
endif
rc = mqsend(mqdes, "Test message")
if (rc < 0)
messagebox(strerror()+",errno="+alltrim(str(error())))
return
endif
mqclose(mqdes)
FOREACH array_expression AS value
statements...
ENDFOR
FOREACH array_expression AS key => value
statements...
ENDFOR
The first form loops over the array given by array_expression. On each loop, the value of the current element is assigned to value and the internal array pointer is advanced by one (so on the next loop, you'll be looking at the next element). The second form does the same thing, except that the current element's key will be assigned to the variable key on each loop. This form works only on associative arrays and objects.
