Apache Server verweigert Zugriff nach gewisser Zeit

Hallo zusammen,
mein Problem ist folgendes: Ich habe Zuhause einen Webserver aufgesetzt und dieser funktioniert auch soweit so wie er soll. Allerdings ist es nun schon das zweite Mal, dass nach 3-4 Wochen der Server auf einmal den Zugriff verweigert. Nach einem Neustart funktioniert wieder alles.
Hat jemand spontan eine Idee woran das liegen könnte?

Google konnte mir bisher nicht weiterhelfen.

Zum System:
Ich verwende einen Raspberry 3 mit Ubuntu und Apache 2.4.18

Schon einmal vielen Dank!

Etwa so,wie du uns eine konkrete Fehlermeldung und den zugehörigen Log-Eintrag verweigert?

Hmmm, wozu die wohl da sind …?

Am 16.10 hat noch alles ohne Probleme funktioniert. Bemerkt habe ich das Problem am 19.10.
Kann jetzt aber auch nicht erkennen was der Fehler sein könnte.

Der Fehlercode der mir im Browser angezeigt wurde war wie im Tag meiner Frage: 403 - Forbidden. Im access.log finde ich aber keinen Eintrag darauf.

error.log:

  [Tue Oct 16 07:35:03.433334 2018] [mpm_prefork:notice] [pid 1117] AH00163: Apache/2.4.18 (Ubuntu) configured -- resuming normal operations
    [Tue Oct 16 07:35:03.433448 2018] [core:notice] [pid 1117] AH00094: Command line: '/usr/sbin/apache2'
    [Wed Oct 17 07:35:03.202522 2018] [mpm_prefork:notice] [pid 1117] AH00171: Graceful restart requested, doing restart
    AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
    [Wed Oct 17 07:35:03.405488 2018] [mpm_prefork:notice] [pid 1117] AH00163: Apache/2.4.18 (Ubuntu) configured -- resuming normal operations
    [Wed Oct 17 07:35:03.405588 2018] [core:notice] [pid 1117] AH00094: Command line: '/usr/sbin/apache2'
    [Thu Oct 18 07:35:03.567164 2018] [mpm_prefork:notice] [pid 1117] AH00171: Graceful restart requested, doing restart
    AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
    [Thu Oct 18 07:35:03.767289 2018] [mpm_prefork:notice] [pid 1117] AH00163: Apache/2.4.18 (Ubuntu) configured -- resuming normal operations
    [Thu Oct 18 07:35:03.767392 2018] [core:notice] [pid 1117] AH00094: Command line: '/usr/sbin/apache2'
    [Thu Oct 18 11:58:15.696663 2018] [mpm_prefork:notice] [pid 1178] AH00163: Apache/2.4.18 (Ubuntu) configured -- resuming normal operations
    [Thu Oct 18 11:58:15.697871 2018] [core:notice] [pid 1178] AH00094: Command line: '/usr/sbin/apache2'
    [Fri Oct 19 18:52:53.086036 2018] [:error] [pid 1966] [client 5.188.210.12:14782] script '/var/www/esky/public_html/echo.php' not found or unable to stat, referer: https://www.google.com/
    [Sat Oct 20 07:35:03.310960 2018] [mpm_prefork:notice] [pid 1178] AH00171: Graceful restart requested, doing restart
    AH00558: apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1. Set the 'ServerName' directive globally to suppress this message
    [Sat Oct 20 07:35:03.450485 2018] [mpm_prefork:notice] [pid 1178] AH00163: Apache/2.4.18 (Ubuntu) configured -- resuming normal operations
    [Sat Oct 20 07:35:03.450592 2018] [core:notice] [pid 1178] AH00094: Command line: '/usr/sbin/apache2'

access.log:

fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:23:13 +0200] "GET / HTTP/1.1" 200 2214 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:24:21 +0200] "GET / HTTP/1.1" 200 2214 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:24:21 +0200] "GET /style/style.css HTTP/1.1" 200 1299 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /script/cookie.js HTTP/1.1" 200 554 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:24:21 +0200] "GET /script/date_validation.js HTTP/1.1" 200 566 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /script/id_generator.js HTTP/1.1" 200 593 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /script/tablesort.js HTTP/1.1" 200 3406 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /script/view_control.js HTTP/1.1" 200 2363 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /media/images/snowflake.png HTTP/1.1" 200 8903 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /media/images/add.png HTTP/1.1" 200 14198 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /media/images/remove.png HTTP/1.1" 200 14050 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /media/images/delete.png HTTP/1.1" 200 17352 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /ico/favicon.icns HTTP/1.1" 200 100213 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
192.168.2.104 - - [19/Oct/2018:18:24:21 +0200] "GET /ico/favicon.ico HTTP/1.1" 200 29200 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET / HTTP/1.1" 200 2214 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /style/style.css HTTP/1.1" 200 1299 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /script/id_generator.js HTTP/1.1" 200 593 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /script/date_validation.js HTTP/1.1" 200 567 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /script/view_control.js HTTP/1.1" 200 2364 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /media/images/remove.png HTTP/1.1" 304 181 "http://esky/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /favicon.ico HTTP/1.1" 404 495 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /favicon.ico HTTP/1.1" 404 495 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /ico/favicon.icns HTTP/1.1" 200 27600 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
fe80::18de:7b84:f12d:8aa - - [19/Oct/2018:18:29:01 +0200] "GET /ico/favicon.ico HTTP/1.1" 200 27600 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
5.188.210.12 - - [19/Oct/2018:18:52:53 +0200] "GET http://5.188.210.12/echo.php HTTP/1.1" 404 464 "https://www.google.com/" "PxBroker/0.3.1/1075"
46.152.99.104 - - [19/Oct/2018:21:08:21 +0200] "GET / HTTP/1.1" 200 9741 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/601.7.7 (KHTML, like Gecko) Version/9.1.2 Safari/601.7.7"
212.129.17.23 - - [19/Oct/2018:22:24:24 +0200] "GET / HTTP/1.1" 200 9797 "-" "-"
186.233.176.154 - - [19/Oct/2018:22:31:33 +0200] "GET / HTTP/1.1" 200 9741 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36"
139.162.119.197 - - [19/Oct/2018:22:40:28 +0200] "GET / HTTP/1.1" 200 9760 "-" "HTTP Banner Detection (https://security.ipip.net)"