[users] Nagios upgrade

Filipe Brandenburger filbranden at gmail.com
Tue Nov 4 15:05:22 CET 2008


Yesterday I did the upgrade to Nagios 3 on my environment. Before
that, I had Nagios 2.9 installed from source, which I backed up and
removed, then I installed Nagios 3 from scratch and configured it. I
did this on a CentOS 5.2 host, i386, fully updated.

I found some little problems:

1) Dependency on libltdl.so.3:

When I first installed it, the "nagios" binary would not work for
nagios -v. I traced it to a library that was not installed. I fixed
this problem with "yum install libtool-ltdl". The dependency seems not
to be on the RPM:

> # yum install nagios
> Loading "fastestmirror" plugin
> Loading "priorities" plugin
> Loading mirror speeds from cached hostfile
>  * rpmforge: mirror.idilia.net
>  * base: mirror.idilia.net
>  * updates: mirror.idilia.net
>  * addons: mirror.idilia.net
> 271 packages excluded due to repository priority protections
> Setting up Install Process
> Parsing package install arguments
> Resolving Dependencies
> --> Running transaction check
> ---> Package nagios.i386 0:3.0.4-1.el5.rf set to be updated
> --> Finished Dependency Resolution
> Dependencies Resolved
> =============================================================================
>  Package                 Arch       Version          Repository        Size
> =============================================================================
> Installing:
>  nagios                  i386       3.0.4-1.el5.rf   rpmforge          3.6 M
> Transaction Summary
> =============================================================================
> Install      1 Package(s)
> Update       0 Package(s)
> Remove       0 Package(s)
> Total download size: 3.6 M
> Is this ok [y/N]: y
> Downloading Packages:
> (1/1): nagios-3.0.4-1.el5 100% |=========================| 3.6 MB    00:00
> Running rpm_check_debug
> Running Transaction Test
> Finished Transaction Test
> Transaction Test Succeeded
> Running Transaction
>   Installing: nagios                       ######################### [1/1]
> Installed: nagios.i386 0:3.0.4-1.el5.rf
> Complete!
> # ldd /usr/bin/nagios
> 	linux-gate.so.1 =>  (0x00ae7000)
> 	libperl.so => /usr/lib/perl5/5.8.8/i386-linux-thread-multi/CORE/libperl.so (0x00101000)
> 	libresolv.so.2 => /lib/libresolv.so.2 (0x00236000)
> 	libnsl.so.1 => /lib/libnsl.so.1 (0x00de5000)
> 	libdl.so.2 => /lib/libdl.so.2 (0x00ccb000)
> 	libm.so.6 => /lib/libm.so.6 (0x00d33000)
> 	libcrypt.so.1 => /lib/libcrypt.so.1 (0x00d8a000)
> 	libutil.so.1 => /lib/libutil.so.1 (0x00249000)
> 	libpthread.so.0 => /lib/libpthread.so.0 (0x00d71000)
> 	libc.so.6 => /lib/libc.so.6 (0x00b86000)
> 	libltdl.so.3 => not found
> 	libglib-2.0.so.0 => /lib/libglib-2.0.so.0 (0x00258000)
> 	libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x00dbe000)
> 	/lib/ld-linux.so.2 (0x00b68000)
> 	librt.so.1 => /lib/librt.so.1 (0x00dd5000)
> #

2) The default configuration does not work, there is an error that
prevents Nagios to start with it:

> # nagios -v /etc/nagios/nagios.cfg
> Nagios 3.0.4
> Copyright (c) 1999-2008 Ethan Galstad (http://www.nagios.org)
> Last Modified: 10-15-2008
> License: GPL
> Reading configuration data...
> Error in configuration file '/etc/nagios/nagios.cfg' - Line 551 (NULL value)
> ***> One or more problems was encountered while processing the config files...
>      Check your configuration file(s) to ensure that they contain valid
>      directives and data defintions.  If you are upgrading from a previous
>      version of Nagios, you should be aware that some variables/definitions
>      may have been removed or modified in this version.  Make sure to read
>      the HTML documentation regarding the config files, as well as the
>      'Whats New' section to find out what has changed.
> #

I looked at it, and line 551 is this one (some lines above as context):
> # These options determine when Nagios will react to detected changes
> # in system time (either forward or backwards).
> time_change_threshold=

Commenting the time_change_threshold variable fixed the problem. I
don't know what it is, but I believe it should come with a default
that would work, but that might be your intent, to make the default
not work so as to force one to edit the config files...

3) This is not a bug per se, but I don't understand why the files
under /etc/nagios are owned by nagios:nagios instead of root:root.
AFAIK, Nagios does not write or change the configfiles at all, I
believe it only shows them on the web interface, but I don't know of
any feature for it to edit its configfiles. Even if it did, I believe
setting the permissions of all those files would be wrong, this should
at least be restricted to the files it must write if any.

Anyway, please have a look at that. Other than that, the package
worked great! Everything is working great for me, and I could say the
upgrade worked just fine, these small issues were not enough to go
ahead with it on my production environment.


More information about the users mailing list