I lack the ability to formulate my problem, otherwise I'd probably find the solution.
I notice there are quite a number of pointless requests in my access log
:~/$ cat /var/log/apache2/access.log | grep -P "GET / HTTP/1.1. 403 \d+ .-. .-." | wc -l
23358
That's for like a bunch of hours. It's clearly not an attack of any kind since those are like a walk in the park for just about any server. I'm really curious to understand what might be causing this.
:~/$ cat /var/log/apache2/access.log | grep -P "GET / HTTP/1.1. 403 \d+ .-. .-." | head
x.y.225.125 - - [27/Aug/2020:06:25:06 +0300] "GET / HTTP/1.1" 403 14779 "-" "-"
x.y.225.125 - - [27/Aug/2020:06:25:07 +0300] "GET / HTTP/1.1" 403 14779 "-" "-"
x.y.245.189 - - [27/Aug/2020:06:25:13 +0300] "GET / HTTP/1.1" 403 15081 "-" "-"
x.y.245.189 - - [27/Aug/2020:06:25:13 +0300] "GET / HTTP/1.1" 403 15081 "-" "-"
x.y.245.189 - - [27/Aug/2020:06:25:13 +0300] "GET / HTTP/1.1" 403 15081 "-" "-"
x.y.245.189 - - [27/Aug/2020:06:25:13 +0300] "GET / HTTP/1.1" 403 15081 "-" "-"
x.y.225.125 - - [27/Aug/2020:06:25:19 +0300] "GET / HTTP/1.1" 403 14779 "-" "-"
x.y.225.125 - - [27/Aug/2020:06:25:19 +0300] "GET / HTTP/1.1" 403 14779 "-" "-"
x.y.225.125 - - [27/Aug/2020:06:25:30 +0300] "GET / HTTP/1.1" 403 14779 "-" "-"
x.y.225.125 - - [27/Aug/2020:06:25:30 +0300] "GET / HTTP/1.1" 403 14779 "-" "-"
All of the requests are coming from about 10 IPs in total.