Apache Troubleshooting
Apache running in Lubuntu Linux stopped accepting connections on https://localhost. The error said “localhost refused to connect”. Using the IP address gave a similar error: “127.0.0.1 refused to connect”. The problem started a few weeks ago, but I didn't have time to troubleshoot it until today.
It worked a month ago, so what changed? Well, I only use my localhost server to host a DokuWiki (DW) wiki that I use for my personal KB. I recently migrated that local version to this blog. After tweaking the online version, I synced it to localhost. I did that for both testing and offline purposes. Now that newly-synced version doesn't work.
Things I tried
Is the Apache service running?
Run this command
sudo service apache2 status
tom /var/log/apache2 $ sudo service apache2 status [sudo] password for tom: apache2.service - The Apache HTTP Server Loaded: loaded (/lib/systemd/system/apache2.service; enabled; vendor preset: enabled) Active: active (running) since Sat 2020-01-11 13:59:54 EST; 28min ago Docs: https://httpd.apache.org/docs/2.4/ Process: 6428 ExecStart=/usr/sbin/apachectl start (code=exited, status=0/SUCCESS) Main PID: 6444 (/usr/sbin/apach) Tasks: 6 (limit: 4915) Memory: 14.3M CGroup: /system.slice/apache2.service ├─6444 /usr/sbin/apache2 -k start ├─6464 /usr/sbin/apache2 -k start ├─6465 /usr/sbin/apache2 -k start ├─6466 /usr/sbin/apache2 -k start ├─6467 /usr/sbin/apache2 -k start └─6468 /usr/sbin/apache2 -k start Jan 11 13:59:54 DellLaptop systemd[1]: Starting The Apache HTTP Server... Jan 11 13:59:54 DellLaptop systemd[1]: Started The Apache HTTP Server.
The service is running, so try something else.
Is the firewall blocking the connection?
Run this command:
sudo ufw disable
Connecting to localhost still gives the same error, so let's try something else.
Is localhost running?
Run this command:
a2query -s
tom /var/log/apache2 $ a2query -s 000-default (enabled by site administrator)
That didn't help, so try something else.
Are there any errors in the log?
First of all, where is the Apache log? To find out, run this command:
grep ErrorLog /etc/apache2/apache2.conf
# ErrorLog: The location of the error log file. # If you do not specify an ErrorLog directive within a <VirtualHost> ErrorLog ${APACHE_LOG_DIR}/error.log
Well, that didn't help much. What does ${APACHE_LOG_DIR} point to? To find out, run this command:
grep APACHE_LOG_DIR /etc/apache2/envvars
My Lubuntu Linux system returned this:
export APACHE_LOG_DIR=/var/log/apache2$SUFFIX
Since I only have one Apache site, $SUFFIX (in the returned value) is empty. So my log directory is: /var/log/apache2.
OK, let's check the log:
tom ~ $ tail -15 /var/log/apache2/error.log [Sat Jan 11 13:29:59.543481 2020] [mpm_prefork:notice] [pid 30745] AH00169: caught SIGTERM, shutting down [Sat Jan 11 13:29:59.720493 2020] [mpm_prefork:notice] [pid 1385] AH00163: Apache/2.4.38 (Ubuntu) mod_apreq2-20090110/2.8.0 mod_perl/2.0.10 Perl/v5.28.1 configured -- resuming normal operations [Sat Jan 11 13:29:59.720598 2020] [core:notice] [pid 1385] AH00094: Command line: '/usr/sbin/apache2' [Sat Jan 11 13:40:54.149537 2020] [mpm_prefork:notice] [pid 1385] AH00169: caught SIGTERM, shutting down [Sat Jan 11 13:40:54.318890 2020] [mpm_prefork:notice] [pid 3266] AH00163: Apache/2.4.38 (Ubuntu) mod_apreq2-20090110/2.8.0 mod_perl/2.0.10 Perl/v5.28.1 configured -- resuming normal operations [Sat Jan 11 13:40:54.318993 2020] [core:notice] [pid 3266] AH00094: Command line: '/usr/sbin/apache2' [Sat Jan 11 13:44:29.498953 2020] [mpm_prefork:notice] [pid 3266] AH00169: caught SIGTERM, shutting down [Sat Jan 11 13:44:29.664837 2020] [mpm_prefork:notice] [pid 3674] AH00163: Apache/2.4.38 (Ubuntu) mod_apreq2-20090110/2.8.0 mod_perl/2.0.10 Perl/v5.28.1 configured -- resuming normal operations [Sat Jan 11 13:44:29.664928 2020] [core:notice] [pid 3674] AH00094: Command line: '/usr/sbin/apache2' [Sat Jan 11 13:46:00.914742 2020] [mpm_prefork:notice] [pid 3674] AH00169: caught SIGTERM, shutting down [Sat Jan 11 13:46:01.076607 2020] [mpm_prefork:notice] [pid 3747] AH00163: Apache/2.4.38 (Ubuntu) mod_apreq2-20090110/2.8.0 mod_perl/2.0.10 Perl/v5.28.1 configured -- resuming normal operations [Sat Jan 11 13:46:01.076705 2020] [core:notice] [pid 3747] AH00094: Command line: '/usr/sbin/apache2' [Sat Jan 11 13:59:54.047966 2020] [mpm_prefork:notice] [pid 3747] AH00169: caught SIGTERM, shutting down [Sat Jan 11 13:59:54.207686 2020] [mpm_prefork:notice] [pid 6444] AH00163: Apache/2.4.38 (Ubuntu) OpenSSL/1.1.1b mod_apreq2-20090110/2.8.0 mod_perl/2.0.10 Perl/v5.28.1 configured -- resuming normal operations [Sat Jan 11 13:59:54.207784 2020] [core:notice] [pid 6444] AH00094: Command line: '/usr/sbin/apache2'
Again, that didn't help. The only “errors” in the error log are about stopping and starting the service.
More details coming soon.
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