CODE server gets and resolve proxy error at random

[digitalrevisor]

Hi.

We have a CODE Collabora server running which we host to be able to edit documents on Nextcloud.

This worked when we sat it up, and it works for a long time, but we have started having issues now.

At seemingly random times our CODE server begins having proxy issues (as far as we can see). The /hosting/discovery endpoint start showing "502 Proxy Error". Our apache2 log is also filled with similar error "Error reading from remote server returned by /hosting/discovery" when this happens.

When the server is working, whenever I open a document I get these types of error messages:

[Tue Aug 25 10:32:26.981805 2020] [proxy_http:error] [pid 10692:tid 139717492336384] (70014)End of file found: [client 178.62.252.54:45168] AH01102: error reading status line from remote s$
[Tue Aug 25 10:32:26.985731 2020] [proxy:error] [pid 10692:tid 139717492336384] [client 122.81.240.21:45168] AH00898: Error reading from remote server returned by /lool/convert-to/png

Does not seem to matter what file I open.

Apache2 settings are:

<IfModule mod_ssl.c>
<VirtualHost *:443>
ServerAdmin webmaster@localhost
DocumentRoot /var/www/html

ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined

ServerName myserver
Include /etc/letsencrypt/options-ssl-apache.conf

# Encoded slashes need to be allowed
AllowEncodedSlashes NoDecode

# Container uses a unique non-signed certificate
SSLProxyEngine on
SSLProxyVerify None
SSLProxyCheckPeerCN Off
SSLProxyCheckPeername Off

# keep the host
ProxyPreserveHost On
  # static html, js, images, etc. served from loolwsd
  # loleaflet is the client part of Collabora Online
ProxyPass /loleaflet https://127.0.0.1:9980/loleaflet retry=0
  ProxyPassReverse /loleaflet https://127.0.0.1:9980/loleaflet

  # WOPI discovery URL
  ProxyPass           /hosting/discovery https://127.0.0.1:9980/hosting/discovery retry=0
  ProxyPassReverse    /hosting/discovery https://127.0.0.1:9980/hosting/discovery

  # Capabilities
  ProxyPass           /hosting/capabilities https://127.0.0.1:9980/hosting/capabilities retry=0
  ProxyPassReverse    /hosting/capabilities https://127.0.0.1:9980/hosting/capabilities

  # Main websocket
  ProxyPassMatch           "/lool/(.*)/ws$" wss://127.0.0.1:9980/lool/$1/ws nocanon

  # Admin Console websocket
  ProxyPass    /lool/adminws wss://127.0.0.1:9980/lool/adminws

  # Download as, Fullscreen presentation and Image upload operations
  ProxyPass /lool https://127.0.0.1:9980/lool
  ProxyPassReverse   /lool https://127.0.0.1:9980/lool

  SSLCertificateFile           /etc/letsencrypt/live/myserver/fullchain.pem
  SSLCertificateKeyFile    /etc/letsencrypt/live/myserver/privkey.pem
</VirtualHost>
</IfModule>

Is there any other logs/configurations/info I can provide that might help identify the cause of this issue?