@Cranvil
Besten dank für deine Mühe.
Hier einmal einen Auszug aus dem error log:
/var/log/apache2/error.log
[Wed Apr 08 00:09:25.372504 2020] [mpm_prefork:notice] [pid 852] AH00163: Apache/2.4.29 (Ubuntu) configu$
[Wed Apr 08 00:09:25.372523 2020] [core:notice] [pid 852] AH00094: Command line: '/usr/sbin/apache2'
/var/log/phpipam-error_log
[Mon Mar 30 16:33:51.716266 2020] [php7:error] [pid 3709] [client 127.0.0.1:58702] PHP Fatal error: Unc$
[Mon Mar 30 16:41:28.345493 2020] [php7:error] [pid 3941] [client 192.168.1.228:49933] PHP Fatal error: $
[Mon Mar 30 16:41:39.329076 2020] [php7:error] [pid 3942] [client 192.168.1.228:49966] PHP Fatal error: $
[Mon Mar 30 16:42:39.939384 2020] [php7:error] [pid 3943] [client 192.168.1.228:50358] PHP Fatal error: $
[Mon Mar 30 16:43:54.222631 2020] [php7:error] [pid 3939] [client 192.168.1.228:50861] PHP Fatal error: $
[Mon Mar 30 16:57:12.291778 2020] [php7:warn] [pid 3942] [client 192.168.1.228:56096] PHP Warning: Crea$
[Mon Mar 30 16:59:52.597085 2020] [php7:warn] [pid 4013] [client 192.168.1.228:57096] PHP Warning: Inva$
[Mon Mar 30 16:59:52.597214 2020] [php7:warn] [pid 4013] [client 192.168.1.228:57096] PHP Warning: Inva$
[Mon Mar 30 17:01:17.584968 2020] [php7:warn] [pid 4066] [client 192.168.1.228:57697] PHP Warning: Inva$
[Mon Mar 30 17:01:17.585087 2020] [php7:warn] [pid 4066] [client 192.168.1.228:57697] PHP Warning: Inva$
[Mon Mar 30 17:01:30.597204 2020] [php7:warn] [pid 4013] [client 192.168.1.228:57776] PHP Warning: Inva$
[Mon Mar 30 17:01:30.597319 2020] [php7:warn] [pid 4013] [client 192.168.1.228:57776] PHP Warning: Inva$
[Mon Mar 30 17:02:01.466128 2020] [php7:warn] [pid 7164] [client 192.168.1.228:57938] PHP Warning: Inva$
[Mon Mar 30 17:02:02.625676 2020] [php7:warn] [pid 7164] [client 192.168.1.228:57938] PHP Warning: Inva$
[Mon Mar 30 17:02:02.625788 2020] [php7:warn] [pid 7164] [client 192.168.1.228:57938] PHP Warning: Inva$
[Mon Mar 30 17:04:42.435921 2020] [php7:warn] [pid 7172] [client 192.168.1.228:59041] PHP Warning: Inva$
[Mon Mar 30 17:05:04.738366 2020] [php7:warn] [pid 7164] [client 192.168.1.228:59182] PHP Warning: size$
[Mon Mar 30 17:05:24.160890 2020] [php7:warn] [pid 7160] [client 192.168.1.228:59299] PHP Warning: size$
[Tue Mar 31 22:43:02.296424 2020] [php7:warn] [pid 902] [client 192.168.1.228:61359] PHP Warning: Inval$
[Tue Mar 31 22:43:02.296894 2020] [php7:warn] [pid 902] [client 192.168.1.228:61359] PHP Warning: Inval$
[Tue Mar 31 22:43:19.925260 2020] [php7:warn] [pid 4290] [client 192.168.1.228:61464] PHP Warning: Inva$
[Tue Mar 31 22:43:19.925375 2020] [php7:warn] [pid 4290] [client 192.168.1.228:61464] PHP Warning: Inva$
[Tue Mar 31 22:43:47.045281 2020] [php7:warn] [pid 4289] [client 192.168.1.228:61620] PHP Warning: Inva$
[Tue Mar 31 22:43:47.045403 2020] [php7:warn] [pid 4289] [client 192.168.1.228:61620] PHP Warning: Inva$
[Tue Mar 31 22:44:25.063035 2020] [php7:warn] [pid 4192] [client 192.168.1.228:61913] PHP Warning: Inva$
[Tue Mar 31 22:45:18.581144 2020] [php7:warn] [pid 5935] [client 192.168.1.228:62206] PHP Warning: Inva$
[Tue Mar 31 22:45:18.581256 2020] [php7:warn] [pid 5935] [client 192.168.1.228:62206] PHP Warning: Inva$
[Tue Mar 31 22:46:11.972602 2020] [php7:warn] [pid 5937] [client 192.168.1.228:62573] PHP Warning: Inva$
[Tue Mar 31 22:46:11.972726 2020] [php7:warn] [pid 5937] [client 192.168.1.228:62573] PHP Warning: Inva$
[Tue Mar 31 22:47:21.143143 2020] [php7:warn] [pid 5937] [client 192.168.1.228:62958] PHP Warning: Inva$
[Tue Mar 31 22:47:21.143247 2020] [php7:warn] [pid 5937] [client 192.168.1.228:62958] PHP Warning: Inva$
Ich muss ganz ehrlich sagen ich habe danach nochmals folgende Befehle ausgeführt
apt -get Update
apt -get update
reboot
Seit dem ist der Fehler nicht wieder aufgetreten. und nicht mehr reproduzierbar, biss jetzt.