Aapache crashes regularly with AH00051

[tux]

Hi,
Apache regularly crashes on one of my VMs with the following message:

[crit] Memory allocation failed, aborting process.
[Fri Sep 06 20:37:04.400866 2024] [core:notice] [pid 220248:tid 220248] AH00051: child pid 220252 exit signal Abort (6), possible coredump in /etc/httpd

The only thing I can observe is that if I remove a random vHost, it no longer occurs.
There is something in the vHost configs.
Here is an example:

<VirtualHost <IPv4>:80 [<IPv6>]:80>
        ServerAdmin <Removed>
        ServerName <Removed>
        RewriteEngine On
        RewriteCond %{HTTPS} !=on
        RewriteRule ^/?(.*) https://%{SERVER_NAME}/$1 [R=301,L]
        LogLevel warn
        ErrorLog /var/log/httpd/<Removed>_error_log
        CustomLog /var/log/httpd/<Removed> combined
</VirtualHost>

<VirtualHost <IPv4>:443 [<IPv6>]:443>
        ServerAdmin <Removed>
        ServerName <Removed>
        Protocols h2 http/1.1 acme-tls/1
SSLEngine on
SSLHonorCipherOrder On
SSLOpenSSLConfCmd Groups "X448:X25519"
SSLCipherSuite PROFILE=SYSTEM
SSLProtocol All -TLSv1.2
Header always set Strict-Transport-Security "max-age=31536000; includeSubDomains; preload"
        Alias /mail/config-v1.1.xml /var/www/autoconfig/config_<Removed>
        LogLevel warn
        ErrorLog /var/log/httpd/<Removed>_ssl_error_log
        CustomLog /var/log/httpd/<Removed>_ssl_access_log combined
</VirtualHost>

Is there a limit to how many vHosts there can be?
Thanks for any advice.

[tux]

In the meantime I found the problem, the mod_md module looks like to be buggy.
Whenever the ACME provider will send an 503 as the return for the cert request the crash will happens. Change the ACME provider for testing will resolve it. So it looks like an bug.