The Object Action Manager framework has given us excellent system management tools, such as SAM, in the past. Recently, the number of tools that have come under the ObAM umbrella has increased; we have seen Partition Manager and Service Control Manager (up to version 2.5) to name but two.

The implementation of the Apache Web server for ObAM is located under the /usr/obam/server directory. This is the ServerRoot; the top-level directory under which the server's configuration, error, and logfiles are kept. Whenever I reference a directory name, I reference it as a subdirectory under ServerRoot. The daemon process for the ObAM-Apache Web server is the process httpd. The configuration file for the daemon is conf/httpd.conf. The configuration file works straight out of the box for just about any installation. The ObAM-Apache Web server is simple and straightforward; it doesn't have many Dynamic Shared Modules and doesn't come with encryption capabilities (SSL = Secure Sockets Layer), so we don't need to worry about digital certificates and the like. The main issue we experience when trying to start up the ObAM-Apache Web server is that it starts up only if we have DNS configured. Part of the configuration file allows access to the Web server only if your node belongs to a DNS domain. It achieves this by using an Allow directive that limits who has access to this server:

root@hpeos002[conf] # pwd
/usr/obam/server/conf
root@hpeos002[conf] # more httpd.conf
#
# Controls who can get stuff from this server.
#
    Order allow,deny

# Change below to reflect domains that may access this server.
# This greatly increases security if it is used.  System names may be
# inserted instead of domain names in order to restrict access to a set
# of specifice systems: Allow from <system1>{ <system N>}*.  Remember to
# restart (#/usr/obam/server/bin/apachectl restart) the server after changing
# anything in this file.
    Allow from insert_domain_here
    AuthName "HPUX Administration Tools"
    AuthType Basic
</Directory>

#
# DirectoryIndex: Name of the file or files to use as a pre-written HTML
# directory index.  Separate multiple entries with spaces.
...
root@hpeos002[conf] #

The first time we run the startup script /sbin/init.d/webadmin start, it fills in the domain name with the domain name it finds inside /etc/resolv.conf. It fails if we do not explicitly configure the domain keyword, even though it is not technically required if you have a searchlist. First, we set up the startup configuration file to ensure that the httpd processes start at boot time:

root@hpeos002[conf] # vi /etc/rc.config.d/webadmin
#!/sbin/sh
# $Header: /kahlua_src/web/server/etc/webadmin 72.1 1999/09/16 03:51:04 lancer E
xp $
# WebAdmin application server configuration.
#
# WEBADMIN:             Set to 1 to start the WebAdmin application server.
#
WEBADMIN=1
root@hpeos002[conf] #

And then we can attempt to start the daemons:

root@hpeos002[conf] # /sbin/init.d/webadmin start
ERROR: No domain is defined in /etc/resolv.conf
root@hpeos002[conf] #

As you can see, this seems strange, even though DNS is configured and working.

root@hpeos002[conf] # nslookup hpeos002
Name Server:  hpeos004.maabof.com
Address:  192.168.0.35

Trying DNS
Name:    hpeos002.maabof.com
Address:  192.168.0.34

root@hpeos002[conf] # cat /etc/resolv.conf
search maabof.com
nameserver 192.168.0.35 # master
nameserver 192.168.0.34 # slave
root@hpeos002[conf] #

It's a minor thing, but one worth knowing. Once we define our domain in /etc/resolv.conf, we have no trouble setting up the daemons:

root@hpeos002[conf] # vi /etc/resolv.conf
domain maabof.com
search maabof.com
nameserver 192.168.0.35 # master
nameserver 192.168.0.34 # slave
root@hpeos002[conf] # /sbin/init.d/webadmin start
/usr/obam/server/bin/apachectl start: httpd started

We can now see what the webadmin startup script has inserted into my httpd.conf file:

root@hpeos002[conf] # more httpd.conf
...
# restart (#/usr/obam/server/bin/apachectl restart) the server after changing
# anything in this file.
    Allow from maabof.com
    AuthName "HPUX Administration Tools"
    AuthType Basic
</Directory>
...
root@hpeos002[conf] #

This limits access to this Web server to machines inside my domain. If you don't have DNS configured but still want to start up the ObAM-Apache Web server, then a workaround is to edit the httpd.conf file directly (keep a backup copy beforehand). The default text the /sbin/init.d/webadmin script is looking for is Allow from insert_domain_here. If you change that to simply say Allow from all, the startup script will not even check for the existence of /etc/resolv.conf.

root@hpeos002[conf] # vi httpd.conf
...
# Change below to reflect domains that may access this server.
# This greatly increases security if it is used. System names may be
# inserted instead of domain names in order to restrict access to a set
# of specifice systems: Allow from <system1>{ <system N>}*. Remember to
# restart (#/usr/obam/server/bin/apachectl restart) the server after changing
# anything in this file.
    Allow from all
    AuthName "HPUX Administration Tools"
    AuthType Basic
...
root@hpeos002[conf] #

This does have a security implication in that any machine on your network can browse to this Web server. You could put in a list of hostnames, as you can see in the comments in the file. Some people would say that because you are not participating in a DNS network, it is highly unlikely you will be connected to the external Internet. I can see their point, but you need to appreciate and accept that before enabling this.

If you are going to make any changes to the httpd.conf file, you should check the syntax of the httpd.conf file (using the /usr/obam/server/bin/apachectl command) before restarting the httpd daemons. Anything other than a Syntax OK from a configtest normally stops the daemons from starting up.

root@hpeos002[conf] # ../bin/apachectl configtest
Syntax OK
root@hpeos002[conf] # ../bin/apachectl restart
../bin/apachectl restart: httpd restarted
root@hpeos002[conf] #

By default, the ObAM-Apache Web server starts up four httpd daemons:

root@hpeos002[conf] # ps -ef | grep httpd
    root  4428  4100  3 13:44:03 pts/0     0:00 grep httpd
webadmin  4425  4421  0 13:43:11 ?         0:00 /usr/obam/server/bin/httpd -f /usr/obam/server/conf/httpd.conf
    root  4421     1  0 13:43:11 ?         0:00 /usr/obam/server/bin/httpd -f /usr/obam/server/conf/httpd.conf
webadmin  4424  4421  0 13:43:11 ?         0:00 /usr/obam/server/bin/httpd -f /usr/obam/server/conf/httpd.conf
webadmin  4423  4421  0 13:43:11 ?         0:00 /usr/obam/server/bin/httpd -f /usr/obam/server/conf/httpd.conf
webadmin  4422  4421  0 13:43:11 ?         0:00 /usr/obam/server/bin/httpd -f /usr/obam/server/conf/httpd.conf
root@hpeos002[conf] #

The StartServers directive in the httpd.conf file controls this:

root@hpeos002[conf] # vi httpd.conf
...
#
# Server-pool size regulation. Rather than making you guess how many
# server processes you need, Apache dynamically adapts to the load it
# sees --- that is, it tries to maintain enough server processes to
# handle the current load, plus a few spare servers to handle transient
# load spikes (e.g., multiple simultaneous requests from a single
# Netscape browser).
#
# It does this by periodically checking how many servers are waiting
# for a request. If there are fewer than MinSpareServers, it creates
# a new spare. If there are more than MaxSpareServers, some of the
# spares die off. The default values are probably OK for most sites.
#
MinSpareServers 1
MaxSpareServers 4

#
# Number of servers to start initially --- should be a reasonable ballpark
# figure.
#
StartServers 4

#
...
root@hpeos002[conf] #

Now that the daemon processes are running, we should be able to browse to the default Web page. Before we do that, we need to know the port number that the httpd daemons are listening on. Unlike the normal Apache configuration (which listens on port 80), the ObAM-Apache configuration listens on a non-standard port number = 1188:

root@hpeos002[conf] # vi httpd.conf
...
#
# Port: The port to which the standalone server listens. For
# ports < 1023, you will need httpd to be run as root initially.
#
Port  1188
...
root@hpeos002[conf] #

The last piece of information we need to know is whether there is a default Web page to view once we get there. The location of documents sourced by the daemons is controlled via the DocumentRoot directive:

root@hpeos002[conf] # grep DocumentRoot httpd.conf
# DocumentRoot: The directory out of which you will serve your
DocumentRoot "/opt/webadmin"
# This should be changed to whatever you set DocumentRoot to.
#    DocumentRoot /www/docs/host.some_domain.com
root@hpeos002[conf] #
root@hpeos002[conf] # ll /opt/webadmin
total 4
dr-xr-xr-x   3 bin        bin           1024 Aug 21  2002 jpi
drwxr-xr-x   3 root       sys             96 Aug 21  2002 mx
dr-xr-xr-x   3 bin        bin             96 Aug 21  2002 obam
dr-xr-xr-x   4 bin        bin           1024 Aug 21  2002 parmgr
root@hpeos002[conf] #

The default page that the Web server displays is controlled by the DirectoryIndex directive. Normally, this defaults to a file called index.html.

root@hpeos002[conf] grep DirectoryIndex httpd.conf
# DirectoryIndex: Name of the file or files to use as a pre-written HTML
DirectoryIndex index.html
root@hpeos002[conf]

As you can see, there is much in the way of an index.html file in our DocumentRoot directory, so if we were to browse to http://www.maabof.com:1188/, we probably wouldn't see very much except some directory names (see Figure 22-1).

Figure 22-1. No default web page for ObAM-Apache Web server.

As you can see, this isn't particularly interesting. The applications that use the ObAM-Apache Web server put their own Web pages under DocumentRoot. One of those applications is Partition Manager:

root@hpeos002[conf] # ll /opt/webadmin/parmgr
total 50
-r--r--r--   1 bin        bin             69 Dec 17  2001 .htaccess
dr-xr-xr-x   2 bin        bin           2048 Aug 21  2002 graphics
dr-xr-xr-x   3 bin        bin             96 Aug 21  2002 help
-r--r--r--   1 bin        bin           1151 Dec 17  2001 index.html
-r-sr-xr-x   1 root       bin          16384 Dec 17  2001 startParMgr.cgi
-r--r--r--   1 bin        bin           3774 Dec 17  2001 web_launch.html
root@hpeos002[conf] #

As we can see in Figure 22-2, there is an index.html file in this directory, so we should see a Web page if we browse there:

Figure 22-2. Partition Manager's default Web page.

Likewise, for any other applications that will make use of this simple Web server, e.g., Service Control Manager (up to version 2.5), we can navigate to http://<server>:1188/mx/. These applications require a plug-in to be applied to your local Web browser. This can be obtained via the main Web page itself. For Partition Manager (see above), the icon to press would be Configure Browser. From that page, there are instructions on how to download the plug-in and configure it for your browser (see Figure 22-3):

Figure 22-3. ObAM-Apache browser plug-in.

Once configured, you can continue to use the browser to manage that particular application.

The full-blown Apache Web server is not started by default on HP-UX. With the current version of the software, the startup configuration file for the Apache Web server is /etc/rc.config.d/hpws_apacheconf (formerly it was called simply /etc/rc.config.d/apacheconf):

root@hpeos002[] # cat /etc/rc.config.d/hpws_apacheconf
# Apache Web Server configuration file

# Set HPWS_APACHE_START to 1 to have the Apache web server started by
# the init process.
HPWS_APACHE_START=0

# Set HPWS_APACHE_HOME to the location of the Apache web server.
# Default is /opt/hpws/apache
HPWS_APACHE_HOME=/opt/hpws/apache
root@hpeos002[] #

Previous versions of the Apache product would have had a single configuration file to control the startup of the Tomcat Servlet engine and Webmin administration tool. All three products have separate startup configuration files:

root@hpeos002[] # cd /etc/rc.config.d
root@hpeos002[rc.config.d] # ll hpws*
-r--r--r--   1 bin        bin            280 Oct 24 18:26 hpws_apacheconf
-r--r--r--   1 bin        bin            437 Dec 10  2002 hpws_tomcatconf
-r--r--r--   1 bin        bin            247 Dec 10  2002 hpws_webminconf
root@hpeos002[rc.config.d] #

The Apache Web server product is installed under /opt/hpws/apache. The configuration file is similar to the ObAM-Apache configuration file. As this is the full-blown product, there are more options as well as the possibility of loading additional Apache modules to enable features such as SSL, and so on. The configuration file resides under /opt/hpws/apache/conf. There should be an httpd-std.default file as well as the http.conf file. The configuration file follows the same layout as the ObAM-Apache configuration file with Global Environment directives, e.g., SystemRoot, and so on, followed by the Main Server configuration and then the Virtual Hosts configuration. This configuration file also has an additional section titled HP-UX Apache-based Web Server Documentation, which references various directories under /opt/hpws/hp_docs and /usr/share for online documentation available via the Web browser itself. This section also includes additional configuration files such as ldap.conf, cache.conf and ssl.conf if necessary.

Something to be aware of is that the Apache does not restrict access to simply my domain in the same way as the ObAM-Apache server did.

root@hpeos002[conf] # pwd
/opt/hpws/apache/conf
root@hpeos002[conf] # more httpd.conf
...
### Section 2: 'Main' server configuration
#
# The directives in this section set up the values used by the 'main'
# server, which responds to any requests that aren't handled by a
...
#
# Controls who can get stuff from this server.
#
    Order allow,deny
    Allow from all

</Directory>
...
root@hpeos002[conf] #

As part of the installation process, a number of directives are set up that you may wish to look at:

root@hpeos002[conf] # grep -e ServerName -e ServerAdmin httpd.conf
# ServerAdmin: Your address, where problems with the server should be
ServerAdmin [email protected]
# ServerName gives the name and port that the server uses to identify itself.
ServerName hpeos002.maabof.com:80
# ServerName directive.
# Set to "EMail" to also include a mailto: link to the ServerAdmin.
# your Apache version number and your ServerAdmin email address regardless
#    ServerAdmin [email protected]
#    ServerName dummy-host.example.com
root@hpeos002[conf] #

You may wish to change the ServerAdmin directive to a valid email address, or alternately to set up an alias for the www email account to direct it to the appropriate place. The ServerName gives you an idea of which port the main Web server listens on by default, port = 80. Instead of using the Port directive, the Listen directive is used to tell the daemon which to bind the main daemon to. The logfile enabled by default is simply the error logfile:

# ErrorLog: The location of the error log file.
# If you do not specify an ErrorLog directive within a <VirtualHost>
# container, error messages relating to that virtual host will be
# logged here. If you *do* define an error logfile for a <VirtualHost>
# container, that host's errors will be logged there and not here.
#
ErrorLog logs/error_log

You might want to look at enabling the access and referrer log files as well.

# The location and format of the access logfile (Common Logfile Format).
# If you do not define any access logfiles within a <VirtualHost>
# container, they will be logged here. Contrariwise, if you *do*
# define per-<VirtualHost> access logfiles, transactions will be
# logged therein and *not* in this file.
#
#CustomLog logs/access_log common

#
# If you would like to have agent and referer logfiles, uncomment the
# following directives.
#
#CustomLog logs/referer_log referer
#CustomLog logs/agent_log agent

#
# If you prefer a single logfile with access, agent, and referer information
# (Combined Logfile Format) you can use the following directive.
#
#CustomLog logs/access_log combined

When we are ready to start the daemon, we can first check the syntax (not the logic) of our logfile with the httpd command. The new version of the software uses the –t option instead of configtest:

root@hpeos002[conf] # ../bin/httpd -t
Syntax OK
root@hpeos002[conf] #
root@hpeos002[conf] # /sbin/init.d/hpws_apache start
Apache Started..
root@hpeos002[conf] #

The default Web page for Apache is a bit more interesting than the null page for the ObAM-Apache server (see Figure 22-4).

Figure 22-4. Apache default Web page.

There are numerous links to help in setting up the Web server. An exceptionally useful link is to Administer the Web server using a browser interface. This is not enabled by default. This is the software component known as Webmin. Getting it up and running is relatively straightforward; we simply edit the startup configuration file and run the startup script.

root@hpeos002[conf] # vi /etc/rc.config.d/hpws_webminconf
# Webmin configuration file

# Set HPWS_WEBMIN_START to 1 to have the Webmin started by the
# init process.
HPWS_WEBMIN_START=1

# Set HPWS_WEBMIN_HOME to the location of the Webmin.
# Default is /opt/hpws/webmin
HPWS_WEBMIN_HOME=/opt/hpws/webmin
root@hpeos002[conf] #
root@hpeos002[conf] # /sbin/init.d/hpws_webmin start
Webmin Started..
root@hpeos002[conf] #

We can now navigate via the Administer hotlink on the default Web page of browse directly to http://www.maabof.com:10000 where we will be asked to log in (username = admin password = hp.com) (see Figure 22-5).

Figure 22-5. Webmin main screen.

At this point, we are getting into configuring Web servers and Virtual Hosts, HTML, XML, the htpasswd command, and the like—a path we never intended going down. With our Web server up and running, we can finish our discussion here.

This short chapter was intended to introduce the concept of using Web servers on HP-UX. HP provides ObAM management tools via a cut-down version of the ever-popular Apache Web server. The full-blown Apache Web server is a free addition to HP-UX, and the configuration file straight out of the box can get a Web server up and running quickly and easily. The default Web page offers extensive help in setting up and managing a Web server. HP looks to be continuing and expanding its use of a Web interface to manage HP-UX. Service Control Manager is currently at version 3.00.04, which utilizes a new standard for management tools known as WBEM, Web-Based Enterprise Management. WBEM allows customers to manage their systems consistently across multiple platforms and operating systems, providing integrated solutions that optimize your infrastructure for greater operational efficiency. WBEM enables management applications to retrieve system information and request system operations wherever and whenever required. See http://www.hp.com/large/infrastructure/management/wbem/ for more details. At its core, Service Control Manager utilizes a Tomcat Web server. Service Control Manager has components that run on HP-UX as well as Linux. From a Central Management Station, we can manage up to 1024 nodes. The software integrated into Service Control Manager includes the following:

This is the future of System Management!