Install icinga2 and icinga-web in different servers

I poked about with this and the problem seems to be within the Agavi components, specifically:

lib/agavi/src/filter/AgaviExecutionFilter.class.php

And within the writeCache() method:

@mkdir(AgaviConfig::get('core.cache_dir') . DIRECTORY_SEPARATOR . 
        self::CACHE_SUBDIR .
        DIRECTORY_SEPARATOR . implode(DIRECTORY_SEPARATOR , 
        array_slice($groups, 0, -1)), 0777, true);

I dropped a logger line into this code and saw that mkdir is trying to recursively create a directory such as:

/usr/local/icinga-www/app/cache/content/amF2YXNjcmlwdF9jb250ZW50/QXBwS2l0X1dpZGdldHMvU3F1aXNoTG9hZGVy

I deleted this, restarted apache but the problem persisted.

At this point the server was running PHP 5.2.17.

I upgraded PHP to 5.3.5 and this issue magically resolved itself.

Out of interest I knocked PHP back to 5.2.17 to see if there were any differences between the mkdir() function behavior in that version compared to the one in 5.3.5. A test script showed that all that PHP did was warn that the folder existed in both versions, there was no hard error thrown.

Also, and bizarrely, icinga-web started working with PHP 5.2.17....and I have no idea why. I checked both version's php.ini files thinking that the error_reporting settings may have changed, but they were the same (except that PHP 5.3.5 is set to E_ALL & ~E_NOTICE | E_DEPRECATED whereas 5.2.17 is set to E_ALL & ~E_NOTICE).

Hope this is of use to anyone else encountering the same issue.

In my case, there were two changes that needed to be made.

1) /etc/default/icinga needs to be configured so that IDO2DB will run:

# start ido2db daemon (no/yes)
IDO2DB=yes

2) The IDO module needs to be defined in /etc/icinga/modules/

/etc/icinga/modules/idoutils.cfg:

define module {
    module_name    ido_mod
    path           /usr/lib/icinga/idomod.so
    module_type    neb
    args           config_file=/etc/icinga/idomod.cfg
    }

The previous config file will, of course, need to match how your system is configured. The above is being used on an Ubuntu 12.10 server.