Debian 10 to 11 ugrade problem

Followed https://www.howtoforge.com/how-to-upgrade-from-debian-10-to-debian-11/ to upgrade my mail server in a multiserver ispconfig 3.2.9p1 system. Server come up so far, mail seems to work, but apache come not up, shows
<code>
Loaded: loaded (/lib/systemd/system/apache2.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Sun 2023-04-16 12:42:51 CEST; 2min 53s ago
Docs: https://httpd.apache.org/docs/2.4/
Process: 480 ExecStart=/usr/sbin/apachectl start (code=exited, status=1/FAILURE)
CPU: 74ms

Apr 16 12:42:46 mail systemd[1]: Starting The Apache HTTP Server...
Apr 16 12:42:50 mail apachectl[540]: apache2: Syntax error on line 146 of /etc/apache2/apache2.conf: Sy>
Apr 16 12:42:51 mail apachectl[480]: Action 'start' failed.
Apr 16 12:42:51 mail apachectl[480]: The Apache error log may have more information.
Apr 16 12:42:51 mail systemd[1]: apache2.service: Control process exited, code=exited, status=1/FAILURE
Apr 16 12:42:51 mail systemd[1]: apache2.service: Failed with result 'exit-code'.
Apr 16 12:42:51 mail systemd[1]: Failed to start The Apache HTTP Server.
</code>

 

just the uncommented lines
<code>
DefaultRuntimeDir ${APACHE_RUN_DIR}
PidFile ${APACHE_PID_FILE}
Timeout 300
KeepAlive On
MaxKeepAliveRequests 100
KeepAliveTimeout 5
User ${APACHE_RUN_USER}
Group ${APACHE_RUN_GROUP}
HostnameLookups Off
ErrorLog ${APACHE_LOG_DIR}/error.log
LogLevel warn
IncludeOptional mods-enabled/*.load
IncludeOptional mods-enabled/*.conf
Include ports.conf
<Directory />
Options FollowSymLinks
AllowOverride None
Require all denied
</Directory>
<Directory /usr/share>
AllowOverride None
Require all granted
</Directory>
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
Require all granted
</Directory>
<FilesMatch "^\.ht">
Require all denied
</FilesMatch>
LogFormat "%v:%p %h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" vhost_combined
LogFormat "%h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" combined
LogFormat "%h %l %u %t \"%r\" %>s %O" common
LogFormat "%{Referer}i -> %U" referer
LogFormat "%{User-agent}i" agent
</code>

 

Updated my master server the same way, apache comes up without error but starting ISPConfig panel it comes up with a internal server error. apache listens only on IPv6. Under Debian 10 I was running everything IPv4 only. i do not need and do not want IPv6

 

I am totally confused now. Did add net.ipv6.conf.all.disable_ipv6 = 1 to /etc/sysctl.conf and rebooted the system. Still the same
<code>
root@isp-master:~# netstat -tulpn |grep apache
tcp6 0 0 :::8080 :::* LISTEN 780/apache2
tcp6 0 0 :::80 :::* LISTEN 780/apache2
tcp6 0 0 :::8081 :::* LISTEN 780/apache2
tcp6 0 0 :::443 :::* LISTEN 780/apache2
</code>
But named i.e. listens to IPv4 on TCP port 53
I have snapshots from bevor the upgrade so I easily can go back, but this is not a solution for ever.
Rainer

 

Oversaw there is an additional tutorial for ISPConfig servers. Restarted from scratch (means set system back to snaphot). Started with them master Server
Everything runs fine, ISPConfig website works fine.
Followed with the mail server, it is used only for mail routing, and postfix works fine. Apache is used only for rspamd, but apache does not start in case of error, error.log below
<code>
apache2: Syntax error on line 146 of /etc/apache2/apache2.conf: Syntax error on line 1 of /etc/apache2/mods-enabled/autoindex.load: Cannot load /usr/lib/apache2/modules/mod_autoindex.so into server: /usr/lib/apache2/modules/mod_autoindex.so: undefined symbol: ap_normalize_path
</code>

systemctl status apache2 shows
<code>
Apr 17 14:09:03 mail systemd[1]: Starting The Apache HTTP Server...
Apr 17 14:09:03 mail apachectl[17921]: AH00534: apache2: Configuration error: No MPM loaded.
Apr 17 14:09:03 mail apachectl[17912]: Action 'start' failed.
Apr 17 14:09:03 mail apachectl[17912]: The Apache error log may have more information.
Apr 17 14:09:03 mail systemd[1]: apache2.service: Control process exited, code=exited, status=1/FAILURE
Apr 17 14:09:03 mail systemd[1]: apache2.service: Failed with result 'exit-code'.
Apr 17 14:09:03 mail systemd[1]: Failed to start The Apache HTTP Server.
</code>

Apache.conf see above

Rainer

 

For anyone haveing same problem, found some php7.0* and php7.3* files in /etc/apache2/mods-available and /etc/apache2/conf-available and remove them.
Apache starts fine now, problem solves