[Koha] Intranet error after upgrade

[Matthew Charlesworth, S.J.]

Hello,

I recently upgraded my library to the following and didn't notice any
errors during the upgrade.

Koha version: 17.11.01.000
   OS version ('uname -a'): Linux ip-172-31-36-26 4.4.0-109-generic
#132-Ubuntu SMP Tue Jan 9 19:52:39 UTC 2018 x86_64
   Perl version: 5.022001
MySQL version: mysql Ver 15.1 Distrib 10.0.33-MariaDB, for debian-linux-gnu
(x86_64) using readline 5.2
   Apache version: Server version: Apache/2.4.18 (Ubuntu)
   Memcached: Servers: undefined
   Zebra version: Zebra 2.0.59

However, when I tried to access the Intranet (https://library.sj.org.za:8080)
Chrome gives an 'Err empty response'. I tried it in Safari and got a
similar message. But I can see the OPAC (https://library.sj.org.za/) just
fine.

On the localhost I can access the Intranet (using lynx), which made me
think perhaps the problem is with Apache to the outside? But Apache is
running. I looked in the error logs and found:

tail /var/log/apache2/error.log
[Sat Jan 20 06:26:11.494741 2018] [mpm_prefork:notice] [pid 8277] AH00163:
Apache/2.4.18 (Ubuntu) mpm-itk/2.4.7-04 OpenSSL/1.0.2g configured --
resuming normal operations
[Sat Jan 20 06:26:11.494755 2018] [core:notice] [pid 8277] AH00094: Command
line: '/usr/sbin/apache2'
[Sat Jan 20 06:26:11.714372 2018] [mpm_prefork:notice] [pid 8277] AH00171:
Graceful restart requested, doing restart
[Sat Jan 20 06:26:11.720326 2018] [core:warn] [pid 8277] AH00111: Config
variable ${instance} is not defined
[Sat Jan 20 06:26:11.720339 2018] [core:warn] [pid 8277] AH00111: Config
variable ${instance} is not defined
[Sat Jan 20 06:26:11.724453 2018] [mpm_prefork:notice] [pid 8277] AH00163:
Apache/2.4.18 (Ubuntu) mpm-itk/2.4.7-04 OpenSSL/1.0.2g configured --
resuming normal operations
[Sat Jan 20 06:26:11.724460 2018] [core:notice] [pid 8277] AH00094: Command
line: '/usr/sbin/apache2'

My vhost configuration for the Intranet is:

<VirtualHost *:8080>
   Include /etc/koha/apache-shared.conf
   Include /etc/koha/apache-shared-intranet.conf

   ServerName library.sj.org.za
   SetEnv KOHA_CONF "/etc/koha/sites/library/koha-conf.xml"
   SetEnv MEMCACHED_SERVERS ""
   SetEnv MEMCACHED_NAMESPACE ""
   AssignUserID library-koha library-koha

   ErrorLog    /var/log/koha/library/intranet-error.log
#  TransferLog /var/log/koha/library/intranet-access.log
#  RewriteLog  /var/log/koha/library/intranet-rewrite.log

ScriptAlias /coverflow.pl "/var/lib/koha/library/plugins/Koha
/Plugin/Com/ByWaterSolutions/CoverFlow/coverflow.pl"
Alias /plugin "/var/lib/koha/library/plugins"
# The stanza below is needed for Apache 2.4+
<Directory /var/lib/koha/library/plugins>
      Options Indexes FollowSymLinks
      AllowOverride None
      Require all granted
</Directory>

SSLCertificateFile /etc/letsencrypt/live/library.sj.org.za/cert.pem
SSLCertificateKeyFile /etc/letsencrypt/live/library.sj.org.za/privkey.pem
Include /etc/letsencrypt/options-ssl-apache.conf
ServerName library.sj.org.za
SSLCertificateChainFile /etc/letsencrypt/live/library.sj.org.za/chain.pem
</VirtualHost>

I'm running this on an Amazon EC2 instance. Has anyone any ideas on why it
would just stop working after a routine sudo apt-get upgrade ?

I'd be grateful for any hints or help.

Matthew