Issue Debian 13: Apache Issues

[Daveo]

Server operating system version

Debian 13.02

Plesk version and microupdate number

18.0.74 #1

I'm running a fresh install of Debian 13 with Plesk on my local server

I restored a full server Plesk backup.

All sites that use nginx are working.

All sites that use Apache don't work.
Error on screen is:
502 Bad Gateway
Web server received an invalid response while acting as a gateway or proxy server.

Log shows...
208308#0: *1 connect() failed (111: Connection refused) while connecting to upstream

If I go to <domain>, I get above error, but <domain>/index.php or htm/html works.

All services are running without any issues.

Any ideas on how to fix ?

 

[Daveo]

Debian version is actually 13.2

 

[Sebahat.hadzhi]

Hello, @Daveo . Have you already tried the repair utility? If not, could you please try:

plesk repair web -y

 

[Daveo]

Just tried it and got this...

# plesk repair web -y

Checking Plesk version .............................................. [OK]

Checking apache configuration ....................................... [OK]

Checking nginx configuration ........................................ [OK]

Checking for custom configuration templates ......................... [OK]

Checking associations between domains and IP addresses .............. [OK]

Checking for corrupted reference between IP collections and  
IPaddresses ......................................................... [OK]

Checking for links between APS applications and subscriptions ....... [OK]

Checking for nginx ULIMIT value ..................................... [OK]

Checking for extra configurations in database not owned by any object
................................................................... [OK]

Checking the status of the required Apache modules .................. [OK]

Checking the configuration of Apache modules ........................ [OK]

Checking web server configuration. Please wait
    Reinstalling SSL/TLS certificates ............................... [OK]
    Applying the default SSL/TLS certificate to all IP addresses .... [OK]
    Repairing web server configuration for all domains. This aspect  
    can be used with individual domains ("plesk repair web          
    example.com"), and on the server level ("plesk repair web") ..... [OK]
    Repairing server-wide configuration parameters for web servers .. [OK]

Checking the usage of PHP handlers .................................. [OK]

Checking for obsolete PHP-FPM configuration files ................... [OK]

Checking php-fpm configuration
    Repairing php-fpm configuration for all domains ................. [OK]

Error messages: 0; Warnings: 0; Errors resolved: 0

Still not fixed the issue, no Apache sites are working. Only nginx sites.

Thinking it may be worth reinstalling system back to Debian 12, instead of Debian 13.

 

[Daveo]

I've reinstalled the server to Debian 12.12.

Installed the things I needed: redis, elasticsearch, samba, nfs and plex.

When I get back home I'll do the following...

Install Plesk
Upgrade MariaDB to 11.4 LTS
Restore full server backup
Check to make sure Apache & nginx sites are working

Will report back where this fixes issue or not.

 

[Daveo]

All done and everything is now working fine again

Not sure why no Apache sites were working after restoring full server backup on Debian 13.

 

[Sebahat.hadzhi]

Glad to hear the issue is sorted. Could you please confirm the configuration of the websites you experienced the issue with prior the migration. More specifically the "Apache & Nginx Settings". When you say served by Apache, I would guess that you mean proxy mode enabled, am I right?

 

[Daveo]

Yes proxy mode was/is enabled on the Apache sites.

I'll get a screenshot of the Apache & Nginx Settings page, as soon as I get back home.

 

[Daveo]

Here are the screenshots of the Apache & Nginx Settings page for one of the sites that is using Apache on my local server.

The Deny * then Allow 192.168.50.0/24 sections limits my sites on local server to allowing local access only.

 

[Sebahat.hadzhi]

Thank you for the screenshots and the provided details. I tried replicating the issue just to make sure there isn't some compatibility issue during Debian 12=>13 migrations, but I was unable to reproduce it, so my guess would be that something went wrong during the migration/restoration process itself.

 

[Daveo]

The process I did was...

Obtain full server backup via Plesk.
Wipe system
Install Debian 13
Install Redis
Install Elasticsearch
Install Plesk (with same setup I had with Debian 12)

Tested everything at this point and all was working as I expected it to be.

Uploaded full server backup to /var
Restored full server backup via CLI/SSH

After this, only NGINX sites worked. No sites using APACHE worked (got 502 Bad Gateway error).

Only difference I noticed is I was running MariaDB 11.4 on Debian 12 & Debian 13 uses MariaDB 11.8.

Just trying to figure out what went wrong. Any ideas what did go wrong?

 

[mow]

The Deny * then Allow 192.168.50.0/24 sections limits my sites on local server to allowing local access only.

Since a while, apache binds to localhost by default.
This is not automatically updated, but a new install will do that, and a restore won't change back to the old setting.

 

[Daveo]

I was trying to access site from another computer on my network, which should of worked but got 502.

Wiped system and install Debian 12 & Plesk then restored backup and everything working fine.

I'm guessing something occurred during restore that broke Apache or something changed between Debian 12 and 13.

 

[mow]

I was trying to access site from another computer on my network, which should of worked but got 502.

But you accessed the nginx port (80 or 443), not the port apache runs on, so the deny/allow settings don't even apply to your connection.