Subject: [bug#27650] [PATCH] gnu: services: admin: Add tailon.

From: [email-masked] (Ludovic Courtès)
Date: Mon, 17 Jul 2017 10:40:11 +0200

Christopher Baines <[email-masked]> skribis:

> On Wed, 12 Jul 2017 14:13:25 +0200

[...]

>> Bonus points if you write a system test that checks that at least the
>> Web server shows up on port 8080.
>
> I've had a go at this, I'll send a separate patch. It doesn't pass for
> me yet, and I'm not sure how to work out what is going on inside the
> test system, does anyone have any tips for writing and debugging system
> tests in general?

No specific tips.  Beware of QEMU port forwarding: it doesn’t allow you
to really diagnose what’s going on if you can’t connect from the host to
the guest (it’s hard to tell if that’s because the service in the guest
is not running.)  So on a few occasions I found that I’d first try
connecting from within the guest as my first attempt (using
‘marionette-eval’), to see if this would work at all.

Sometimes you’ll also want to just run a VM of the system under test
interactively so experiment a bit.

HTH,
Ludo’.