I just noticed that there are multiple messages per file, so I have to adapt the parser. I'll update this thread when I'm done!

Where is this feature documented?

I'm probably too tired or I don't know, but of course I looked at the user's guide and the admin's guide but did not found anything about this ;-) Is there another documention which I missed somehow?

OK thanks I'll check that out. I did not configure ELOG by myself, I only use it and wrote the Slack plugin ;-)

We were running ELOG for many many years in our experiments and the instance was operated on a Debian XEN server as a container. I am now trying to migrate it into our Docker Swarm cluster and I am using the https://hub.docker.com/r/de1lz/elog-docker Docker image, which works very well with our logbooks when I run it as a single container. However, when I put the container behind my load balancer (HAProxy) using the simple HTTP mode (which works very well for all the other HTTP-based services) with this simple configuration:

backend be_elog.km3net.de
    mode http
    server-template km3net-elog- 1 km3net-elog_elog:8080 check resolvers docker init-addr libc,none

I get a "too many redirects" error when I try to access one of the logbooks. The starting page works fine, but every other link leads to a pile-up of redirects.

Here is the current instance running, where you can see the behaviour: https://elog.test.km3net.de (all log entries deleted and only two logbooks activated)

My question is: what kind of redirect could go wrong here? I don't know how the internal HTTP server of ELOG works, but maybe someone faced similar issues.

My ELOG configuration is also pretty basic, and as I wrote above, everything works when I run it without the load balancer (single instance at the moment). Here is the top part of the configuration, it contains a few dozens of logbooks but they are configured the very same way. 

;User Settings
;=============
Password file = login.xml
Admin user = km3net_admin
Self register = 0
Allow password change = 0
Allow config = km3net_admin

;Group Settings:
;====
Group ELOGKM3NET = Operations IT, Operations FR

[Operations IT]
Subdir = Operations_IT
Theme = default
Default encoding = 0
Comment = KM3NeT IT Detector Operations
Attributes = Author, Type, Subject
Options Author = A, B, C
Options Type = PPM-DOM, PPM-DU, Comment, Power cut, New run
Extendable Options = Type
Required Attributes = Author, Type, Subject
Page Title = ELOG - $subject
;Sort Attributes = Author, Type
Quick filter = Date, Type, Author
Resubmit default = 2
Reverse sort = 1
Menu commands = List, New, Edit, Reply, Duplicate, Find, Config, Help, Logout
Preset on first reply Subject = Re: $Subject
Preset on reply author =

Thanks for the quick reply! Sorry, I forgot to paste the "global" part of the config, I have that URL already set:

[global]
;Main Settings
;=============
Usr = elog
Grp = elog
port = 8080
SSL = 0
URL = https://elog.test.km3net.de
Title image = <img border=0 src="KM3NeT_logo.png" alt="KM3NeT logo" height="35px">
;SMTP host = smtp.fau.de
Display mode = summary
Thumbnail size = 500>
List Menu text = clock.html
Menu text = clock.html

I also tried the default configuration (example config) and it that works behind the load balancer. So I guess it's related to the password-page, which causes this redirect loop? Our logbooks are all password protected, so when a logbook URL is clicked, it should first present the login-form, and that's where it chokes.

My problem is that I don't even reach the page where I can enter a password. If you go to https://elog.test.km3net.de and click on a logbook, you'll see that it immediately goes into a redirect loop. I already logged the routing but there is nothing else...