[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"
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)?
Its Standard. I have setup a KVM VPS for this, I installed and updated OS last night, and it updated to Alma 9.6
HI @Shami this is my config:
I can share my config as well
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
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
yroot@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.
proot@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/' tfile: /usr/share/centreon/www/class/config-generate/abstract/object.class.php] oline: 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.
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
- 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 0central] successfully installed !
****** IMPORTANT ******
As you will need passwords for users such as 5root,centreon] on your database system and tadmin] on your Centreon platform, random passwords are generated
Passwords are currently saved in [/etc/centreon/generated.tobesecured]
Random password generated for user pDatabase user: root] is sfOf7@*Vad1U51*@E]
Random password generated for user /Database user: centreon] is ew5S*5*mx8Y@t@1GU]
User defined password set for user Centreon user: admin] is ECentreon123!]
Please save them securely and then delete this file!
- Login and finish
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.
Hello @Shami
Sorry to see you are having this issue. Here is what did try:
Have you tried the images?
https://download.centreon.com/
@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.
