Nagios Support Forum

I have hit another snag in my installation of Nagios 3.3.1 on a Linux Ubuntu server with an Intel base processor.

Apache is running, Nagios is running

Open web browers type https://localhost/nagios and I get the following:
Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, webmaster@localhost and inform them of the time the error occurred, and anything
you might have done that may have caused the error.

More information about this error may be available in the server error log.
Apache/2.2.20 (Ubuntu) Server at localhost Port 80

Base on the reading articles on the this support forum it appears that this is permission issue. I checked the Apache error.log file and access was being denied to the "/usr/local/nagios/etc/htpasswd.users" file.

I attempted changed permission using the following:
chown nagios:nagios /usr/local/nagios/etc/htpasswd.user
chmod 755 /usr/local/nagios/etc/htpasswd.user

The the Apache error.log is as follows at this point in time:
root@Octoberfest:/# tail -f /var/log/apache2/error.log
[Tue May 01 14:29:55 2012] [error] [client 127.0.0.1] File does not exist: /var/www/favicon.ico
[Tue May 01 14:29:55 2012] [error] [client 127.0.0.1] File does not exist: /var/www/favicon.ico
[Tue May 01 14:30:19 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local /nagios/etc/htpasswd.users
[Tue May 01 15:33:17 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users
[Tue May 01 15:42:52 2012] [error] [client 127.0.0.1] File does not exist: /var/www/nagios3
[Tue May 01 16:01:53 2012] [notice] caught SIGTERM, shutting down
[Tue May 01 16:01:54 2012] [notice] Apache/2.2.20 (Ubuntu) PHP/5.3.6-13ubuntu3.6 with Suhosin-Patch configured -- resuming normal operations
[Tue May 01 16:15:01 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users
[Tue May 01 16:15:06 2012] [error] [client 127.0.0.1] File does not exist: /var/www/nagios3
[Tue May 01 16:15:13 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users

I also have been looking at the installation guide here:
http://www.unixmen.com/install-nagios-u ... x-and-10x/

In this guide it states to edit the "apache.conf" file, which I have done per instructions.

Specifically:
sudo vi /etc/apache2/apache2.conf
and add this line
DirectoryIndex index.html index.php index.cgi
.....

sudo vi /etc/apache2/apache.conf

and add these lines :

ScriptAlias /nagios/cgi-bin /usr/local/nagios/sbin
Options ExecCGI
AllowOverride None
Order allow,deny
Allow from all
AuthType Basic
AuthUserFile /usr/local/nagios/etc/htpasswd.users
Require valid-user
Alias /nagios /usr/local/nagios/share
Options None
AllowOverride None
Order allow,deny
Allow from all
AuthType Basic
AuthUserFile /usr/local/nagios/etc/htpasswd.users
Require valid-user
save and exit then restart apache2

Upon the restarting Apache I get the following messages:
root@Octoberfest:/# service apache2 restart
[Tue May 01 16:53:36 2012] [warn] The ScriptAlias directive in /etc/apache2/apache2.conf at line 236 will probably never match because it overlaps an earlier ScriptAlias.
Syntax error on line 238 of /etc/apache2/apache2.conf:
AllowOverride not allowed here
Action 'configtest' failed.
The Apache error log may have more information.
...fail!

The Apache error.log file is as follows:
root@Octoberfest:/# tail -f /var/log/apache2/error.log
[Tue May 01 14:29:55 2012] [error] [client 127.0.0.1] File does not exist: /var/www/favicon.ico
[Tue May 01 14:29:55 2012] [error] [client 127.0.0.1] File does not exist: /var/www/favicon.ico
[Tue May 01 14:30:19 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users
[Tue May 01 15:33:17 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users
[Tue May 01 15:42:52 2012] [error] [client 127.0.0.1] File does not exist: /var/www/nagios3
[Tue May 01 16:01:53 2012] [notice] caught SIGTERM, shutting down
[Tue May 01 16:01:54 2012] [notice] Apache/2.2.20 (Ubuntu) PHP/5.3.6-13ubuntu3.6 with Suhosin-Patch configured -- resuming normal operations
[Tue May 01 16:15:01 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users
[Tue May 01 16:15:06 2012] [error] [client 127.0.0.1] File does not exist: /var/www/nagios3
[Tue May 01 16:15:13 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users

I realize I have provided alot of information here. I am new to Nagios, Apache, and Linux. I am reading before asking questions to gain some understanding. I am trying to figure out if this is an Apache issue or a Nagios issue.

I have tried several different things here, and I am not sure if they have helped me or mislead me.

Thank you in advance for any assistance, about this issue.

I have a feeling that your initial problem at least is a misconfiguration in the apache config (/etc/apache2/apache2.conf) file... are you able to post the file in its entirety?

Yes, here is the "apache2.conf file:

#
# Based upon the NCSA server configuration files originally by Rob McCool.
#
# This is the main Apache server configuration file. It contains the
# configuration directives that give the server its instructions.
# See http://httpd.apache.org/docs/2.2/ for detailed information about
# the directives.
#
# Do NOT simply read the instructions in here without understanding
# what they do. They're here only as hints or reminders. If you are unsure
# consult the online docs. You have been warned.
#
# The configuration directives are grouped into three basic sections:
# 1. Directives that control the operation of the Apache server process as a
# whole (the 'global environment').
# 2. Directives that define the parameters of the 'main' or 'default' server,
# which responds to requests that aren't handled by a virtual host.
# These directives also provide default values for the settings
# of all virtual hosts.
# 3. Settings for virtual hosts, which allow Web requests to be sent to
# different IP addresses or hostnames and have them handled by the
# same Apache server process.
#
# Configuration and logfile names: If the filenames you specify for many
# of the server's control files begin with "/" (or "drive:/" for Win32), the
# server will use that explicit path. If the filenames do *not* begin
# with "/", the value of ServerRoot is prepended -- so "foo.log"
# with ServerRoot set to "/etc/apache2" will be interpreted by the
# server as "/etc/apache2/foo.log".
#

### Section 1: Global Environment
#
# The directives in this section affect the overall operation of Apache,
# such as the number of concurrent requests it can handle or where it
# can find its configuration files.
#

#
# ServerRoot: The top of the directory tree under which the server's
# configuration, error, and log files are kept.
#
# NOTE! If you intend to place this on an NFS (or otherwise network)
# mounted filesystem then please read the LockFile documentation (available
# at <URL:http://httpd.apache.org/docs/2.2/mod/mp ... l#lockfile>);
# you will save yourself a lot of trouble.
#
# Do NOT add a slash at the end of the directory path.
#
#ServerRoot "/etc/apache2"

#
# The accept serialization lock file MUST BE STORED ON A LOCAL DISK.
#
LockFile ${APACHE_LOCK_DIR}/accept.lock

#
# PidFile: The file in which the server should record its process
# identification number when it starts.
# This needs to be set in /etc/apache2/envvars
#
PidFile ${APACHE_PID_FILE}

#
# Timeout: The number of seconds before receives and sends time out.
#
Timeout 300

#
# KeepAlive: Whether or not to allow persistent connections (more than
# one request per connection). Set to "Off" to deactivate.
#
KeepAlive On

#
# MaxKeepAliveRequests: The maximum number of requests to allow
# during a persistent connection. Set to 0 to allow an unlimited amount.
# We recommend you leave this number high, for maximum performance.
#
MaxKeepAliveRequests 100

#
# KeepAliveTimeout: Number of seconds to wait for the next request from the
# same client on the same connection.
#
KeepAliveTimeout 5

##
## Server-Pool Size Regulation (MPM specific)
##

# prefork MPM
# StartServers: number of server processes to start
# MinSpareServers: minimum number of server processes which are kept spare
# MaxSpareServers: maximum number of server processes which are kept spare
# MaxClients: maximum number of server processes allowed to start
# MaxRequestsPerChild: maximum number of requests a server process serves
<IfModule mpm_prefork_module>
StartServers 5
MinSpareServers 5
MaxSpareServers 10
MaxClients 150
MaxRequestsPerChild 0
</IfModule>

# worker MPM
# StartServers: initial number of server processes to start
# MinSpareThreads: minimum number of worker threads which are kept spare
# MaxSpareThreads: maximum number of worker threads which are kept spare
# ThreadLimit: ThreadsPerChild can be changed to this maximum value during a
# graceful restart. ThreadLimit can only be changed by stopping
# and starting Apache.
# ThreadsPerChild: constant number of worker threads in each server process
# MaxClients: maximum number of simultaneous client connections
# MaxRequestsPerChild: maximum number of requests a server process serves
<IfModule mpm_worker_module>
StartServers 2
MinSpareThreads 25
MaxSpareThreads 75
ThreadLimit 64
ThreadsPerChild 25
MaxClients 150
MaxRequestsPerChild 0
</IfModule>

# event MPM
# StartServers: initial number of server processes to start
# MinSpareThreads: minimum number of worker threads which are kept spare
# MaxSpareThreads: maximum number of worker threads which are kept spare
# ThreadsPerChild: constant number of worker threads in each server process
# MaxClients: maximum number of simultaneous client connections
# MaxRequestsPerChild: maximum number of requests a server process serves
<IfModule mpm_event_module>
StartServers 2
MinSpareThreads 25
MaxSpareThreads 75
ThreadLimit 64
ThreadsPerChild 25
MaxClients 150
MaxRequestsPerChild 0
</IfModule>

# These need to be set in /etc/apache2/envvars
User ${APACHE_RUN_USER}
Group ${APACHE_RUN_GROUP}

#
# AccessFileName: The name of the file to look for in each directory
# for additional configuration directives. See also the AllowOverride
# directive.
#

AccessFileName .htaccess

#
# The following lines prevent .htaccess and .htpasswd files from being
# viewed by Web clients.
#
<Files ~ "^\.ht">
Order allow,deny
Deny from all
Satisfy all
</Files>

#
# DefaultType is the default MIME type the server will use for a document
# if it cannot otherwise determine one, such as from filename extensions.
# If your server contains mostly text or HTML documents, "text/plain" is
# a good value. If most of your content is binary, such as applications
# or images, you may want to use "application/octet-stream" instead to
# keep browsers from trying to display binary files as though they are
# text.
#
DefaultType text/plain


#
# HostnameLookups: Log the names of clients or just their IP addresses
# e.g., www.apache.org (on) or 204.62.129.132 (off).
# The default is off because it'd be overall better for the net if people
# had to knowingly turn this feature on, since enabling it means that
# each client request will result in AT LEAST one lookup request to the
# nameserver.
#
HostnameLookups Off

# 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 ${APACHE_LOG_DIR}/error.log
#
# LogLevel: Control the number of messages logged to the error_log.
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
#
LogLevel warn

# Include module configuration:
Include mods-enabled/*.load
Include mods-enabled/*.conf

# Include all the user configurations:
Include httpd.conf

# Include ports listing
Include ports.conf

#
# The following directives define some format nicknames for use with
# a CustomLog directive (see below).
# If you are behind a reverse proxy, you might want to change %h into %{X-Forwarded-For}i
#
LogFormat "%v:%p %h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" vhost_combined
LogFormat "%h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" combined
LogFormat "%h %l %u %t \"%r\" %>s %O" common
LogFormat "%{Referer}i -> %U" referer
LogFormat "%{User-agent}i" agent

# Include of directories ignores editors' and dpkg's backup files,
# see README.Debian for details.

# Include generic snippets of statements
Include conf.d/

# Include the virtual host configurations:
Include sites-enabled/

#Configure Apache to use PHP
DirectoryIndex index.html index.php index.cgi

#Configure Apache to use Nagios
ScriptAlias /nagios/cgi-bin /usr/local/nagios/sbin
Options ExecCGI
AllowOverride None
Order allow,deny
Allow from all
AuthType Basic
AuthUserFile /usr/local/nagios/etc/htpasswd.users
Require valid-user
Alias /nagios /usr/local/nagios/share
Options None
AllowOverride None
Order allow,deny
Allow from all
AuthType Basic
AuthUserFile /usr/local/nagios/etc/htpasswd.users
Require valid-user

You're missing the <Directory/> tags, don't copy and paste this (it's probably not quite right for you because I am using Nagios XI on CentOS) but to give you an example of what it should look like:

ScriptAlias /nagios/cgi-bin "/usr/local/nagios/sbin"

<Directory "/usr/local/nagios/sbin">
Options ExecCGI
AllowOverride None
Order allow,deny
Allow from all
AuthName "Nagios Core"
AuthType Basic
AuthUserFile /usr/local/nagiosxi/etc/htpasswd.users
Require valid-user
</Directory>

Alias /nagios "/usr/local/nagios/share"

<Directory "/usr/local/nagios/share">
Options None
AllowOverride None
Order allow,deny
Allow from all
AuthName "Nagios Core"
AuthType Basic
AuthUserFile /usr/local/nagiosxi/etc/htpasswd.users
Require valid-user
</Directory>

I am not forgetting my issue. I get pulled in several direction and cannot alway focus on the task at hand. Thank you for the guidance with the Directory tagged. I admit I following information blindly.

I added the directory tags I am still having the same issue. I have however taken a step back. The statement that were missing the Directory tags are located in /conf.d directory in a file called nagios.conf.

The apache2.conf has an include statement for directory conf.d, I believe this mean that the nagios.conf is getting processed correctly. I did comment out the nagios configuration statement in the apache2.conf file.

This maybe a silly question, but when I log into Ubuntu I sign in as tknutson. Issue the command sudo -s so, I am a root user. Should I be signing in as "nagios"?

Nagios is running as a service within Apache correct? Do I need to enable Nagios as an available site?

Sorry this does not solve your problem, but I can answer a few of your side questions. The Nagios monitoring engine is running as its own service on the Linux machine, while the web interface is running under Apache via CGI. Also, you should not need to sign in as the nagios user except when you testing nagios check plugins.

Whoops I forgot about this, I got interrupted in the middle of answering last week and then forgot about it.

I was wondering why the configuration data was put in the apache.conf rather than in its own file in conf.d/ I just sort of assumed it might be a ubuntu eccentricity. As long as it exists conf.d/ all should be good in the world.

I noticed in your original post that there are two entries:
[Tue May 01 15:33:17 2012] [error] [client 127.0.0.1] (2)No such file or directory: Could not open password file: /usr/local/nagios/etc/htpasswd.users
[Tue May 01 15:42:52 2012] [error] [client 127.0.0.1] File does not exist: /var/www/nagios3

The second one is obviously looking for nagios in a completely different directory... is the conf.d/ nagios apache file set to look for it in a location other than /usr/local/nagios?

Anyway, with the configuration issues (presumably) resolved are you still getting the same error message about the password file? Sorry to ask such an obvious question but does the password file exist? Is Nagios actually installed in /usr/local/nagios?

Success!

To answer your questions:
Yes, Nagios is installed in usr/local/nagios
Yes, the password file "htpasswd.user" existed in usr/local/nagios/etc

The htpasswd.user file was the issue. In the nagios.conf file it was htpasswd.userS, with an "s" not htpasswd.user as in the usr/local/nagios/etc directory. I removed the "s" in the nagios.conf file. Stopped Apache, stopped Nagios, started Apache, started Nagios, when to the web brower /localhost/nagios, logged in as "nagiosadmin" and poof the Nagios webpage appeared.

Thank you so much for all the assistance, with this issue. I am now onto the next step in my network monitoring adventure, with Nagios.

Awesome! Glad you found the solution, I'll have to keep that in mind for next time... I didn't think for a second that the reference in the conf file might have been the issue.