4 Known Issues and Workaround

Topics

In IBM AIX, OHS Server Startup Fails Even After Successful Installation and Configuration of Oracle HTTP Server

Issue

Impacted Platforms: IBM AIX

After successful installation and configuration of Oracle HTTP Server 12.2.1.3.0 , the Oracle HTTP Server (OHS) startup fails with following error:

exec(): 0509-036 Cannot load program httpd because of the following errors: 
rtld: 0712-001 Symbol CreateIoCompletionPort was referenced from module $ORACLE_HOME/wlserver/../lib/libclntsh.so(), but a runtime definition of the symbol was not found.

Workaround

Oracle HTTP Server 12.2.1.3.0 is bundled with IBM AIX Database client 12.1.0.2.0 version. The issue is related to the IOCP API symbols dependency in IBM AIX Database 12.1.0.2 client library. Enable the IOCP module in the machine where Oracle HTTP Server is installed to resolve this issue.

On IBM AIX in IBM POWER Systems (64-Bit), enable I/O completion ports (IOCP) before initiating the install process. To enable IOCP ports, set the status of the IOCP port to Available.

To check if the IOCP port is Available, enter the lsdev command as follows: 
$ lsdev | grep iocp
By default, IOCP status is set to Defined, and hence not enabled. The following example output shows that the IOCP status is set to Defined: 
iocp0 Defined I/O Completion Ports

Complete the following steps to set IOCP status to Available:

  1. Log in as root and run the following command: 
    smitty iocp
  2. Select Change / Show Characteristics of I/O Completion Ports.
  3. Change configured state at system restart from Defined to Available.
  4. Run the lsdev command to confirm the IOCP status is set to Available. 
    $ lsdev | grep iocp 
iocp0 Available I/O Completion Ports
  5. Perform a system restart to make the changes permanent.

In IBM AIX, Continuously Hitting Web Application Through Oracle HTTP Server Generates a Large Error Log

Issue

Impacted Platforms: IBM AIX

IBM AIX users continuously hitting a web application that has many users (for example, greater than 400) through Oracle HTTP Server might experience a large error log being generated.

Workaround

This is a performance tuning issue that can be corrected by updating some of the IBM AIX system parameters and Oracle HTTP Server tuning parameters.

For example,

For IBM AIX system parameters:

  1. Ensure that the following parameters are available in /etc/security/limits:

    nofiles = -1
nofiles_hard = -1
  2. Ensure that the following parameters are available in /etc/rc.net: 
    /usr/sbin/no -o sb_max=6192000
/usr/sbin/no -o tcp_sendspace=4096000
/usr/sbin/no -o tcp_recvspace=4096000
/usr/sbin/no -o udp_sendspace=65536
/usr/sbin/no -o udp_recvspace=655360
/usr/sbin/no -o rfc1323=1
/usr/sbin/no -o ipqmaxlen=150
/usr/sbin/no -o clean_partial_conns=true

  3. Restart the computer.

For Oracle HTTP Server Configuration:

  1. Set the mod_wl_ohs.conf file to look like the following example:

    LoadModule weblogic_module   "${PRODUCT_HOME}/modules/mod_wl_ohs.so"
# This empty block is needed to save mod_wl related configuration from EM to this file when changes are made at the Base Virtual Host Level

<IfModule weblogic_module>
#      WebLogicHost <WEBLOGIC_HOST>
#      WebLogicPort <WEBLOGIC_PORT>
#      MatchExpression *.jsp
WebLogicCluster <host-name>:<port>,<host-name>:<port>,<host-name>:<port>
ConnectTimeoutSecs 99999 //[Optional parameter]
WLIOTimeoutSecs 99999 //[default value 300]
WLSocketTimeoutSecs 99999 //[default value 2]
MatchExpression *

<Location /diagservlet>
#      SetHandler weblogic-handler
       WLSRequest On
       WebLogicCluster
<host-name>:<port>,<host-name>:<port>,<host-name>:<port>
#      PathTrim /weblogic
#      ErrorPage  http:/WEBLOGIC_HOME:WEBLOGIC_PORT/
          </Location>

</IfModule>

  2. Set the following in the httpd.conf file:

    <IfModule mpm_worker_module>
          -
          -
          -
MinSpareThreads     200 [default value 25]
MaxSpareThreads     800 [default value 75]
          -
          -
          -
          -
</IfModule>

Dynamic Monitoring Service Displays Incorrect Message if Oracle HTTP Server is Down

Issue

Impacted Platforms: Generic

If you try to get metrics when Oracle HTTP Server is not running, Dynamic Monitoring Service (DMS) displays an incorrect message on displayMetricTables.display: 
 wls:/nm/base_domain> displayMetricTables(servers='ohs1',servertype='OHS')
Traceback (innermost last):
 File "<console>", line 1, in ?
File "/scratch/prkishor/ps3_stg21_sa/oracle_common/modules/oracle.dms/diagnostics-common-wlst.jar!/wlstScriptDir/OracleDMS.py", 
line 71, in displayMetricTables
File "<string>", line 1085, in oracledmsDisplayMetricTables
File "<string>", line 661, in oracledmsHandleException
ImportError: no module named socket

Workaround

No workaround available.

No Automatic Port Allocation for Standalone Instances

Issue

Impacted Platforms: Generic

In the standalone mode, there is no automatic port allocation for Oracle HTTP Server instances.

Workaround

No workaround available.

Problem Setting MPM Name in Fusion Middleware Control

Issue

Impacted Platforms: Generic

The operation of setting Multi-Processing Module (MPM) name succeeds but a false misleading message stating that it has failed appears.

The following error message appears:

Error Setting performance Directives

Workaround

Retry the operation until it succeeds.

Metrics Fail to Load after Restarting Oracle HTTP Server Through Oracle Enterprise Manager Fusion Middleware Control Console on HP IA

Issue

Impacted Platforms: Generic

After a successful collocated Oracle HTTP Server installation on the HP IA–64 platform, Oracle HTTP Server startup metrics fail to load if you restart Oracle HTTP Server instance through Oracle Enterprise Manager Fusion Middleware Control console. You might get one of the following errors:

"Metrics are currently unavailable"

"Metrics are not configured"

Workaround

Logout and log in from Oracle Enterprise Manager Fusion Middleware Control console aftee Oracle HTTP Server starts.

WebLogic Server Plug-ins for Apache

Issue

Impacted Platforms: Generic

If an IPv6 address is specified for WebLogicHost or WebLogicCluster parameter, then WebLogic Server plug-in may be unable to resolve this IPv6 address. This is due to missing or corrupted DLL errors in the Apache Portable Runtime (APR) project library that is shipped with Apache httpd 2.2.x. The underlying APR library is libapr-1.dll. .

This issue applies to WebLogic Server plug-ins for Apache 2.2 on Windows only, and is not applicable to Oracle HTTP Server or any other Listeners or Web Servers.

Workaround

This issue is resolved in Apache httpd 2.2.24.