I think I can reproduce this on my server. I changed the apache config as follows and called lynx a few times. After a few successful lynxes, the server no longer responds. What can i do to debug more? apache config: StartServers 1 MinSpareThreads 1 MaxSpareThreads 1 ThreadsPerChild 1 MaxRequestWorkers 1 MaxConnectionsPerChild 1 # systemctl restart apache2.service # tail -f /var/log/apache2/error.log [Wed Aug 31 22:45:54.390886 2022] [mpm_event:notice] [pid 998699:tid 139894640904064] AH00492: caught SIGWINCH, shutting down gracefully [Wed Aug 31 22:45:54.649967 2022] [:notice] [pid 1000585:tid 140120599648128] ModSecurity for Apache/2.9.5 (http://www.modsecurity.org/) configured. [Wed Aug 31 22:45:54.650003 2022] [:notice] [pid 1000585:tid 140120599648128] ModSecurity: APR compiled version="1.7.0"; loaded version="1.7.0" [Wed Aug 31 22:45:54.650016 2022] [:notice] [pid 1000585:tid 140120599648128] ModSecurity: PCRE compiled version="8.39 "; loaded version="8.39 2016-06-14" [Wed Aug 31 22:45:54.650023 2022] [:notice] [pid 1000585:tid 140120599648128] ModSecurity: LUA compiled version="Lua 5.1" [Wed Aug 31 22:45:54.650029 2022] [:notice] [pid 1000585:tid 140120599648128] ModSecurity: YAJL compiled version="2.1.0" [Wed Aug 31 22:45:54.650035 2022] [:notice] [pid 1000585:tid 140120599648128] ModSecurity: LIBXML compiled version="2.9.12" [Wed Aug 31 22:45:54.650094 2022] [:notice] [pid 1000585:tid 140120599648128] ModSecurity: StatusEngine call: "2.9.5,Apache/2.4.52 (Ubuntu),1.7.0/1.7.0,8.39/8.39 2016-06-14,Lua 5.1,2.9.12,e0c86efba80afb51d5e1caae78c38635f2f8b5df" [Wed Aug 31 22:46:02.727769 2022] [suexec:notice] [pid 1000585:tid 140120599648128] AH01232: suEXEC mechanism enabled (wrapper: /usr/lib/apache2/suexec) [Wed Aug 31 22:46:02.982447 2022] [ssl:warn] [pid 1000591:tid 140120599648128] AH01909: broeltal.de:443:0 server certificate does NOT include an ID which matches the server name [Wed Aug 31 22:46:03.025496 2022] [mpm_event:notice] [pid 1000591:tid 140120599648128] AH00489: Apache/2.4.52 (Ubuntu) OpenSSL/3.0.2 mod_fcgid/2.3.9 configured -- resuming normal operations [Wed Aug 31 22:46:03.025617 2022] [core:notice] [pid 1000591:tid 140120599648128] AH00094: Command line: '/usr/sbin/apache2' after 3 successfully lynx commands: [Wed Aug 31 22:46:18.046440 2022] [mpm_event:error] [pid 1000591:tid 140120599648128] AH00484: server reached MaxRequestWorkers setting, consider raising the MaxRequestWorkers setting # ps xaufe root 1000591 0.5 0.2 69388 18392 ? Ss 22:46 0:00 /usr/sbin/apache2 -k start root 1000593 0.0 0.0 3088 1164 ? S 22:46 0:00 \_ /usr/bin/rotatelogs -l /www/foo1_log 3600 root 1000594 0.0 0.0 3088 1136 ? S 22:46 0:00 \_ /usr/bin/rotatelogs -l /www/foo2_log 1800 www-data 1000597 0.0 0.1 69332 13424 ? S 22:46 0:00 \_ /usr/sbin/apache2 -k start www-data 1000644 0.0 0.1 233620 14836 ? Sl 22:46 0:00 \_ /usr/sbin/apache2 -k start $ lynx -dump -read_timeout=10 localhost/server-status Apache Server Status for localhost (via 127.0.0.1) Server Version: Apache/2.4.52 (Ubuntu) OpenSSL/3.0.2 mod_fcgid/2.3.9 Server MPM: event Server Built: 2022-06-14T12:30:21 __________________________________________________________________ Current Time: Wednesday, 31-Aug-2022 22:46:12 CEST Restart Time: Wednesday, 31-Aug-2022 22:46:03 CEST Parent Server Config. Generation: 1 Parent Server MPM Generation: 0 Server uptime: 9 seconds Server load: 0.29 0.17 0.09 Total accesses: 0 - Total Traffic: 0 kB - Total Duration: 0 CPU Usage: u.25 s.02 cu0 cs0 - 3% CPU load 0 requests/sec - 0 B/second 0 requests currently being processed, 0 idle workers Slot PID Stopping Connections Threads Async connections total accepting busy idle writing keep-alive closing 0 1000598 yes 0 no 0 0 0 0 0 Sum 1 1 0 0 0 0 0 0 W Scoreboard Key: "_" Waiting for Connection, "S" Starting up, "R" Reading Request, "W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup, "C" Closing connection, "L" Logging, "G" Gracefully finishing, "I" Idle cleanup of worker, "." Open slot with no current process Srv PID Acc M CPU SS Req Dur Conn Child Slot Client Protocol VHost Request 0-0 1000598 1/0/0 W 0.00 0 0 0 0.0 0.00 0.00 127.0.0.1 http/1.1 servername.domain.de:80 GET /server-status HTTP/1.0 __________________________________________________________________ Srv Child Server number - generation PID OS process ID Acc Number of accesses this connection / this child / this slot M Mode of operation CPU CPU usage, number of seconds SS Seconds since beginning of most recent request Req Milliseconds required to process most recent request Dur Sum of milliseconds required to process all requests Conn Kilobytes transferred this connection Child Megabytes transferred this child Slot Total megabytes transferred this slot __________________________________________________________________ mod_fcgid status: Total FastCGI processes: 0 __________________________________________________________________ SSL/TLS Session Cache Status: cache type: SHMCB, shared memory: 512000 bytes, current entries: 0 subcaches: 32, indexes per subcache: 88 index usage: 0%, cache usage: 0% total entries stored since starting: 0 total entries replaced since starting: 0 total entries expired since starting: 0 total (pre-expiry) entries scrolled out of the cache: 0 total retrieves since starting: 0 hit, 0 miss total removes since starting: 0 hit, 0 miss __________________________________________________________________ Apache/2.4.52 (Ubuntu) Server at localhost Port 80 $ lynx -dump -read_timeout=10 localhost/server-status Apache Server Status for localhost (via 127.0.0.1) Server Version: Apache/2.4.52 (Ubuntu) OpenSSL/3.0.2 mod_fcgid/2.3.9 Server MPM: event Server Built: 2022-06-14T12:30:21 __________________________________________________________________ Current Time: Wednesday, 31-Aug-2022 22:46:15 CEST Restart Time: Wednesday, 31-Aug-2022 22:46:03 CEST Parent Server Config. Generation: 1 Parent Server MPM Generation: 0 Server uptime: 12 seconds Server load: 0.29 0.17 0.09 Total accesses: 1 - Total Traffic: 4 kB - Total Duration: 1 CPU Usage: u.25 s.02 cu0 cs0 - 2.25% CPU load .0833 requests/sec - 341 B/second - 4096 B/request - 1 ms/request 0 requests currently being processed, 0 idle workers Slot PID Stopping Connections Threads Async connections total accepting busy idle writing keep-alive closing 1 1000613 yes 0 no 0 0 0 0 0 Sum 1 1 0 0 0 0 0 0 .W Scoreboard Key: "_" Waiting for Connection, "S" Starting up, "R" Reading Request, "W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup, "C" Closing connection, "L" Logging, "G" Gracefully finishing, "I" Idle cleanup of worker, "." Open slot with no current process Srv PID Acc M CPU SS Req Dur Conn Child Slot Client Protocol VHost Request 0-0 - 0/0/1 . 0.00 2 1 1 0.0 0.00 0.00 127.0.0.1 http/1.1 servername.domain.de:80 GET /server-status HTTP/1.0 1-0 1000613 1/0/0 W 0.00 0 0 0 0.0 0.00 0.00 127.0.0.1 http/1.1 servername.domain.de:80 GET /server-status HTTP/1.0 __________________________________________________________________ Srv Child Server number - generation PID OS process ID Acc Number of accesses this connection / this child / this slot M Mode of operation CPU CPU usage, number of seconds SS Seconds since beginning of most recent request Req Milliseconds required to process most recent request Dur Sum of milliseconds required to process all requests Conn Kilobytes transferred this connection Child Megabytes transferred this child Slot Total megabytes transferred this slot __________________________________________________________________ mod_fcgid status: Total FastCGI processes: 0 __________________________________________________________________ SSL/TLS Session Cache Status: cache type: SHMCB, shared memory: 512000 bytes, current entries: 0 subcaches: 32, indexes per subcache: 88 index usage: 0%, cache usage: 0% total entries stored since starting: 0 total entries replaced since starting: 0 total entries expired since starting: 0 total (pre-expiry) entries scrolled out of the cache: 0 total retrieves since starting: 0 hit, 0 miss total removes since starting: 0 hit, 0 miss __________________________________________________________________ Apache/2.4.52 (Ubuntu) Server at localhost Port 80 $ lynx -dump -read_timeout=10 localhost/server-status Apache Server Status for localhost (via 127.0.0.1) Server Version: Apache/2.4.52 (Ubuntu) OpenSSL/3.0.2 mod_fcgid/2.3.9 Server MPM: event Server Built: 2022-06-14T12:30:21 __________________________________________________________________ Current Time: Wednesday, 31-Aug-2022 22:46:16 CEST Restart Time: Wednesday, 31-Aug-2022 22:46:03 CEST Parent Server Config. Generation: 1 Parent Server MPM Generation: 0 Server uptime: 13 seconds Server load: 0.26 0.17 0.09 Total accesses: 2 - Total Traffic: 9 kB - Total Duration: 2 CPU Usage: u.25 s.02 cu0 cs.01 - 2.15% CPU load .154 requests/sec - 708 B/second - 4608 B/request - 1 ms/request 0 requests currently being processed, 0 idle workers Slot PID Stopping Connections Threads Async connections total accepting busy idle writing keep-alive closing 0 1000626 yes 0 no 0 0 0 0 0 Sum 1 1 0 0 0 0 0 0 W Scoreboard Key: "_" Waiting for Connection, "S" Starting up, "R" Reading Request, "W" Sending Reply, "K" Keepalive (read), "D" DNS Lookup, "C" Closing connection, "L" Logging, "G" Gracefully finishing, "I" Idle cleanup of worker, "." Open slot with no current process Srv PID Acc M CPU SS Req Dur Conn Child Slot Client Protocol VHost Request 0-0 1000626 1/0/1 W 0.00 0 0 1 0.0 0.00 0.00 127.0.0.1 http/1.1 servername.domain.de:80 GET /server-status HTTP/1.0 1-0 - 0/0/1 . 0.00 0 1 1 0.0 0.00 0.00 127.0.0.1 http/1.1 servername.domain.de:80 GET /server-status HTTP/1.0 __________________________________________________________________ Srv Child Server number - generation PID OS process ID Acc Number of accesses this connection / this child / this slot M Mode of operation CPU CPU usage, number of seconds SS Seconds since beginning of most recent request Req Milliseconds required to process most recent request Dur Sum of milliseconds required to process all requests Conn Kilobytes transferred this connection Child Megabytes transferred this child Slot Total megabytes transferred this slot __________________________________________________________________ mod_fcgid status: Total FastCGI processes: 0 __________________________________________________________________ SSL/TLS Session Cache Status: cache type: SHMCB, shared memory: 512000 bytes, current entries: 0 subcaches: 32, indexes per subcache: 88 index usage: 0%, cache usage: 0% total entries stored since starting: 0 total entries replaced since starting: 0 total entries expired since starting: 0 total (pre-expiry) entries scrolled out of the cache: 0 total retrieves since starting: 0 hit, 0 miss total removes since starting: 0 hit, 0 miss __________________________________________________________________ Apache/2.4.52 (Ubuntu) Server at localhost Port 80 $ lynx -dump -read_timeout=10 localhost/server-status Looking up localhost Making HTTP connection to localhost Sending HTTP request. HTTP request sent; waiting for response. Alert!: Socket read failed (too many tries). Connection interrupted. lynx: Can't access startfile http://localhost/server-status $ lynx -dump -read_timeout=10 localhost/server-status Looking up localhost Making HTTP connection to localhost Sending HTTP request. HTTP request sent; waiting for response. Alert!: Socket read failed (too many tries). Connection interrupted. lynx: Can't access startfile http://localhost/server-status $