[lubuntu-users] Lubuntu 16.04 PPC: Cacti stopped working after PHP upgrade

[Aere Greenway]

On 03/26/2016 07:16 AM, Peter Golis wrote:
> Hello Gentleman,
> Yesterday, after upgrade of PHP v7 package with removal of older version of PHP v5 had stopped working my Cacti instance. What had please happened with PHP v5, was it marked as obsolete?
>   
> Error in cacti.log had pointed to missing function mb_strlen() which was moved into separate package php7.0-mbstring in PHP v7. After installing it, Cacti was back in life. That simply point to wrong dependencies for package Cacti. Are somewhere tested also dependencies for packages?
>   
> [Fri Mar 25 21:23:20.098957 2016] [:error] [pid 18311] [client 127.0.0.1:34556] PHP Fatal error:  Uncaught Error: Call to undefined function mb_strlen() in /usr/share/cacti/site/lib/rrd.php:1049\nStack trace:\n#0 /usr/share/cacti/site/graph_image.php
> (92): rrdtool_function_graph('36', '0', Array)\n#1 {main}\n  thrown in /usr/share/cacti/site/lib/rrd.php on line 1049, referer: http://rybnik.zapto.org/cacti/graph_view.php
>   
> Have a nice day,
> Peter.
>
Peter:

I don't know how you originally installed Cacti, so I am speculating 
here, with a generality.

When we install software from sources other than the Ubuntu repository, 
or Debian packages, the package manager is not aware of what other 
packages your 'custom install' software requires.

So (being unaware of the requirements), it may allow packages not 
required by software installed from the repository (or other Debian 
packages), to be marked as 'not needed', or perhaps 'obsolete'.

Un-needed or obsolete packages get removed when you upgrade to a new 
system level.

I am speculating that this situation may have come into-play in the 
problem you reported.

-- 
Sincerely,
Aere