Error with fresh install with new version

[root@monitoring ~]# ls -ld /var/cache/centreon/config/engine/*
-rw------- 1 apache centreon    0 May 21 09:59 /var/cache/centreon/config/engine/tmpdir_8AzpTn
drwxrwx--- 2 apache centreon 4096 May 21 09:59 /var/cache/centreon/config/engine/tmpdir_8AzpTn.d
-rw------- 1 apache centreon    0 May 21 10:00 /var/cache/centreon/config/engine/tmpdir_mY0kjq
drwxrwx--- 2 apache centreon 4096 May 21 10:00 /var/cache/centreon/config/engine/tmpdir_mY0kjq.d
-rw------- 1 apache centreon    0 May 21 09:59 /var/cache/centreon/config/engine/tmpdir_V7Kf7E
drwxrwx--- 2 apache centreon 4096 May 21 09:59 /var/cache/centreon/config/engine/tmpdir_V7Kf7E.d

[root@monitoring ~]# stat /var/cache/centreon/config/engine/
  File: /var/cache/centreon/config/engine/
  Size: 4096            Blocks: 8          IO Block: 4096   directory
Device: 801h/2049d      Inode: 271452      Links: 5
Access: (6775/drwsrwsr-x)  Uid: (  983/centreon)   Gid: (  983/centreon)
Access: 2025-04-18 18:14:53.000000000 +0500
Modify: 2025-05-21 10:00:11.714572721 +0500
Change: 2025-05-21 10:00:11.714572721 +0500
 Birth: 2025-05-21 02:37:32.728165837 +0500

It’s default installation. No poller added, (just using the central one) 
Haven’t done anything really. 

Looking at the previous posts, looking around. People have been having similar issues (With older version) for almost 2 years now. 

Let me try and find an expert to help you here. Out of curiosity, is your Alma standard or a hardened one (e.g. CIS compliant)?

HI ​@Shami this is my config:

# ls -lah /var/cache/centreon/config/
total 0
drwsrwsr-x 6 centreon centreon 62 Apr 18 15:14 .
drwxrwxr-x 6 centreon centreon 68 Apr 23 13:00 ..
drwsrwsr-x 2 centreon centreon  6 Apr 18 15:14 broker
drwsrwsr-x 2 centreon centreon  6 Apr 18 15:14 engine
drwsrwsr-x 2 centreon centreon  6 Apr 18 15:14 export
drwsrwsr-x 3 centreon centreon 15 Apr 18 15:14 vmware

# cat /etc/os-release
NAME="AlmaLinux"
VERSION="9.5 (Teal Serval)"
ID="almalinux"

Its Standard. I have setup a KVM VPS for this, I installed and updated OS last night, and it updated to Alma 9.6
 

I can share my config as well 
 

[root@monitoring ~]# ls -lah /var/cache/centreon/config/
total 24K
drwsrwsr-x 6 centreon centreon 4.0K May 21 02:37 .
drwxrwxr-x 5 centreon centreon 4.0K May 21 02:49 ..
drwsrwsr-x 3 centreon centreon 4.0K May 21 02:52 broker
drwsrwsr-x 7 centreon centreon 4.0K May 21 10:37 engine
drwsrwsr-x 2 centreon centreon 4.0K Apr 18 18:14 export
drwsrwsr-x 3 centreon centreon 4.0K May 21 02:52 vmware

[root@monitoring ~]# cat /etc/os-release
NAME="AlmaLinux"
VERSION="9.6 (Sage Margay)"
ID="almalinux"
ID_LIKE="rhel centos fedora"
VERSION_ID="9.6"
PLATFORM_ID="platform:el9"
PRETTY_NAME="AlmaLinux 9.6 (Sage Margay)"
ANSI_COLOR="0;34"
LOGO="fedora-logo-icon"
CPE_NAME="cpe:/o:almalinux:almalinux:9::baseos"
HOME_URL="https://almalinux.org/"
DOCUMENTATION_URL="https://wiki.almalinux.org/"
BUG_REPORT_URL="https://bugs.almalinux.org/"

ALMALINUX_MANTISBT_PROJECT="AlmaLinux-9"
ALMALINUX_MANTISBT_PROJECT_VERSION="9.6"
REDHAT_SUPPORT_PRODUCT="AlmaLinux"
REDHAT_SUPPORT_PRODUCT_VERSION="9.6"
SUPPORT_END=2032-06-01

Honestly, while trying to find fix on the forums and going through docs, I can see the whole setup (Using RPM method) has a mix of file/directory permission between “apache” and “centreon”
I don’t know why though. sticking with one user/group would have been much nicer. 

Just to show what I am trying to say 

[root@monitoring ~]# ls -al  /var/lib/centreon/installs/
total 12
drwxrwxr-x  3 centreon centreon 4096 May 21 02:50 .
drwxrwxr-x 11 centreon centreon 4096 May 21 02:38 ..
drwxr-xr-x  9 apache   apache   4096 May 21 02:50 install-24.10.7-20250521_025036

Hi ​@Shami I installed Centreon 24.10.7 on AlmaLinux 9.6 and I don’t have your issue.

Can you check groups definition?

# cat /etc/group | egrep "(apache|centreon)"
apache:x:48:nagios,centreon-gorgone,centreon
nagios:x:990:centreon-engine,centreon-broker,apache
centreon-broker:x:989:apache,nagios,centreon,centreon-engine,centreon-gorgone
centreon-engine:x:988:centreon-broker,nagios,apache,centreon,centreon-gorgone
centreon:x:987:centreon-broker,centreon-engine,centreon-gorgone,apache
centreon-gorgone:x:986:centreon,centreon-engine,centreon-broker,apache

Can you try to restart httpd and php-fpm?

systemctl daemon-reload
systemctl restart php-fpm httpd

Then try to export configuration again

​@Laurent 
This is interesting. If it worked for you, I might have messed up then 😞
Althouh I am pretty sure, I followed everything exactly as given at 
https://docs.centreon.com/docs/installation/installation-of-a-central-server/using-packages/

After that, I just added license, enabled few connectors, nothing else is done yet. 

[root@monitoring ~]# cat /etc/group | egrep "(apache|centreon)"
apache:x:48:nagios,centreon-gorgone,centreon
nagios:x:986:centreon-engine,centreon-broker,apache
centreon-broker:x:985:apache,nagios,centreon,centreon-engine,centreon-gorgone
centreon-engine:x:984:centreon-broker,nagios,apache,centreon,centreon-gorgone
centreon:x:983:centreon-broker,centreon-engine,centreon-gorgone,apache
centreon-gorgone:x:981:centreon,centreon-engine,centreon-broker,apache

I have done reload/restart of all services (any that I could fine) and have rebooted server a few times as well. 

The error happens when “Generate Configuration Files” is checked. 
I just did that (after an other reboot/restart) and I get 

 

Preparing environment... OK
Generating files... NOK (Exception received : Cannot open file (writing permission) '/var/cache/centreon/config/engine/tmpdir_BFfW0O.d/' [file: /usr/share/centreon/www/class/config-generate/abstract/object.class.php] [line: 223] )
Aborted.

This is what I see in that directory 
 

[root@monitoring ~]# ls -lah /var/cache/centreon/config/engine/tmpdir_BFfW0O.d/
total 100K
drwxrwx--- 2 apache   centreon 4.0K May 21 13:25 .
drwsrwsr-x 8 centreon centreon 4.0K May 21 13:25 ..
-rw-rw---- 1 apache   apache   2.4K May 21 13:25 centengine.DEBUG
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 commands.cfg
-rw-rw---- 1 apache   apache   2.2K May 21 13:25 connectors.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 contactgroups.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 contacts.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 dependencies.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 escalations.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 hostgroups.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 hosts.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 hostTemplates.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 meta_commands.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 meta_host.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 meta_services.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 meta_timeperiod.cfg
-rw-r--r-- 1 apache   apache      2 May 21 13:25 otl_server.json
-rw-r--r-- 1 apache   apache      2 May 21 13:25 plugins.json
-rw-rw---- 1 apache   apache   1.2K May 21 13:25 resource.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 servicegroups.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 services.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 serviceTemplates.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 severities.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 tags.cfg
-rw-rw---- 1 apache   apache   1.1K May 21 13:25 timeperiods.cfg

Should I try to “re-install” everything again?
If so, is Alma9 a preferred OS or generally Debian 12 is more “suited” for Centreon? Or there is no difference / preference?? 
Just want to get going with stable, reliable and maintainable Monitoring solution :) 
 

Did any errors occur during installation (/var/log/dnf.rpm.log)?

You can try to restart on new AlmaLinux 9 or move to Debian 12.

No, no error at all. 
I still do not see any error in logs. (other than what’s obviously comes up a permission error) 

Is there a way to fix it ?? I am note sure why it’s giving permission error when I have not changed anything and all user/groups seem to be setup properly. 

What’s your preferred OS for Centreon ? If I am going to start again, I would really like not to end up in the same situation again :( 

I guess we will never know what happened here and why I am having issue with it. 
And looks like there is no “fix” for it either. 

I did fine some one year / 2 year old posts here having “similar” issue with permission error for the same directory. 

I will give it an other try, hoping it will work. 
Since I didn’t get any response for the “preferred os” part, I will stick with Alma 9 and see if it works any better this time. 

🤞

hello, there is no preferred OS, Alma 9 will do just fine. I hope your second attempt worked?

Just an update. 

I tried to install it again with Fresh Almalinux 9.6, using packages method, followed every step, ended up in the same situation. 

Tried to install it again using “Unattended” method, ended up with the same “permission error” while exporting files. 
 

Honestly, this is becoming more annoying and frustrating. I know I am a new user of Centreon. But I never thought it will be that difficult to setup. :( In all attempts, I never got any error during installation. No warning, nothing. So it seemed like eveything was setup properly. It just does not want to work 


I tried again to install with Debian 12. It worked this time. No more “permission errors” but I believe I am seeing different issue now. I would still call it a “broken” setup that can not be used for monitoring anything reliably. 

I really want to use Centreon (I like the interface, I like how it gives cleaner options, but so far, it looks like it doesn’t like me) 

I never had any issue with Zabbix ever for at least installation and initial setup. The docs on Zabbix are pretty straight forward and crystal clear for a w working setup. 

Needless to say, having a pretty disappointed experience so far. 

Hello ​@Shami 

Sorry to see you are having this issue. Here is what did try:

• new alma9 download from
  • https://mirror.csclub.uwaterloo.ca/almalinux/9.6/isos/x86_64/AlmaLinux-9-latest-x86_64-dvd.iso
  • Name: AlmaLinux-9-latest-x86_64-dvd.iso
    Size: 12287213568 bytes : 11 GiB
    SHA256: db7b45e071b6319d43781eb8d9bec9b8d6b0ac41ad5e49db7fe113c76f0d2ca2
• Minimal install with standard software
• reboot and update

  • AlmaLinux 9 - AppStream                3.8 MB/s | 9.6 MB     00:02
    AlmaLinux 9 - BaseOS                    10 MB/s | 4.8 MB     00:00
    AlmaLinux 9 - Extras                    64 kB/s |  20 kB     00:00
    Dependencies resolved.
    =======================================================================
     Package              Arch    Version                 Repository  Size
    =======================================================================
    Installing:
     kernel               x86_64  5.14.0-570.17.1.el9_6   baseos     1.8 M
    Upgrading:
     kernel-tools         x86_64  5.14.0-570.17.1.el9_6   baseos     2.0 M
     kernel-tools-libs    x86_64  5.14.0-570.17.1.el9_6   baseos     1.8 M
     python3-perf         x86_64  5.14.0-570.17.1.el9_6   appstream  3.2 M
     webkit2gtk3-jsc      x86_64  2.48.2-1.el9_6          appstream  8.5 M
     xdg-utils            noarch  1.1.3-13.el9_6          appstream   71 k
    Installing dependencies:
     kernel-core          x86_64  5.14.0-570.17.1.el9_6   baseos      18 M
     kernel-modules       x86_64  5.14.0-570.17.1.el9_6   baseos      39 M
     kernel-modules-core  x86_64  5.14.0-570.17.1.el9_6   baseos      31 M

    Transaction Summary
    =======================================================================
    Install  4 Packages
    Upgrade  5 Packages

    Total download size: 104 M
    Is this ok [y/N]: y

     …..

    …..

    
    Installed:
      kernel-5.14.0-570.17.1.el9_6.x86_64
      kernel-core-5.14.0-570.17.1.el9_6.x86_64
      kernel-modules-5.14.0-570.17.1.el9_6.x86_64
      kernel-modules-core-5.14.0-570.17.1.el9_6.x86_64

    Complete!

• Get unattended script and use
  • https://download.centreon.com/24.10/unattended.sh --output /tmp/unattended.sh
  • bash /tmp/unattended.sh install -t central -v 24.10 -r stable -s -p Centreon123! -l DEBUG  2>&1 |tee -a /tmp/unattended-$(date +"%m-%d-%Y-%H%M%S").log

  • ...
    ...
    2025-05-26 12:33:49-04:00 - INFO -  wizard install step process_step9.php response ->  200
    2025-05-26 12:33:49-04:00 - INFO - Log in to Centreon web interface via the URL: http://192.168.1.26/centreon
    2025-05-26 12:33:49-04:00 - INFO - Centreon [central] successfully installed !

    ****** IMPORTANT ******
    As you will need passwords for users such as [root,centreon] on your  database system and [admin] on your Centreon platform, random passwords are generated
    Passwords are currently saved in [/etc/centreon/generated.tobesecured]
    Random password generated for user [Database user: root] is [fOf7@*Vad1U51*@E]
    Random password generated for user [Database user: centreon] is [w5S*5*mx8Y@t@1GU]
    User defined password set for user [Centreon user: admin] is [Centreon123!]

    Please save them securely and then delete this file!

• ​​​​​​​Login and finish
  • https://docs.centreon.com/docs/installation/web-and-post-installation/#initialization-of-the-monitoring

  • 

    

    

Have you tried the images?

https://download.centreon.com/

I was able to install with the unattended script

https://mirror.csclub.uwaterloo.ca/almalinux/9.6/isos/x86_64/AlmaLinux-9-latest-x86_64-dvd.iso

Name: AlmaLinux-9-latest-x86_64-dvd.iso
Size: 12287213568 bytes : 11 GiB
SHA256: db7b45e071b6319d43781eb8d9bec9b8d6b0ac41ad5e49db7fe113c76f0d2ca2
minimall install with standard software
 

It appears that Centreon is unable to write configuration files due to improper file permissions. The temporary directory `/var/cache/centreon/config/engine/tmpdir_glGLrg.d/` seems to be causing the problem. This most likely occurred after enabling the trial license or after installing Base Connectors which changed ownership and/or file permissions for the directory. The fix should involve confirming that the Centreon user (in this case most likely centreon or centreon-engine) has write privileges to the directory. Commands to consider using are something like `chown -R centreon:centreon /var/cache/centreon` and `chmod -R 775 /var/cache/centreon`. Then try export again. Overall there was a lot of upheaval at the beginning but a setup problem like this is not a systemic failure and is fixable.

​@ponchoh Thank you so much. Really appreciate you taking time and trying to troubleshoot. 

I think I have figured it out. The monitoring server I wanted to setup is hosted on Leaseweb, on their cloud VPS. The have Base Alma9 Image and I can not really use my own ISO. 
Something is broken or working entirely different on their setup. Even with multiple tries, I was hitting the same permission error with Alma 9. 🤐

I tried to set it up on a test VM (one my own KVM host) running Alma9 and it worked just fine. 😐
So even though frustrating for me, it wasn’t really a Centreon issue. 😔

But I do want the monitoring server outside my setup. That’s why I switched to Debian 12. And with Debian 12, I am not seeing any “permission” related issues at least. 

There are however other issue with Debain 12 setup. (may be not on Alma9) 

rchauvel acknowledged it here. 

Hello, I recently encountered the same issue, though not on a fresh installation. Under Configuration > Pollers > Engine configuration, I noticed that one of the pollers was disabled, which caused the error. Re-enabling it resolved the issue.

In my case this might be related to an update in version 24.10.7 to 24.10.8. In 24.10.8, it seems the engine can’t be deactivated without also disabling the poller. However, in my case, the poller was enabled.

It’s possible the same applies to a fresh installation. Since there are no screenshots of the Engine configuration, it’s hard to say for sure. In any case, the error message is misleading.