Hello everybody!

I have a big problem with my Koha installation for the small library in my primary school. After an update it does not run any more. With my technical experience I am now at the end and hope you can help me. I hope I got the right mailing list.

What is used?

Operating System: Ubuntu Server 18.04 LTS

Koha: 18.05.01 stable

OPAC: https://lesehoehle.foerderverein-hellwegschule.de

What's the matter?

Every few weeks I upgrade Ubuntu and Koha, if something is pending. I recorded the last upgrade yesterday, but since then I can't use Koha anymore.

When calling the website I get the following error message:

The proxy server received an invalid response from an upstream server.

The proxy server could not handle the request GET /index.html.

Reason: Error reading from remote server

A matching error message seems to be in the Plack-error log:

Error while loading /etc/koha/plack.psgi: Can't load application from file "/usr/share/koha/api/v1/app.pl": [JSON::Validator] GET http://json-schema.org/draft-04/schema == Connection refused at /usr/share/perl5/JSON/Validator.pm line 274.

Compilation failed in require at (eval 1524) line 1.

Child process 15572 exited with status 111

Can you help me?

Thank you and many greetings

Sven