TemplateVMs have issues connecting to DNF

[Nemo]

My TemplateVMs have a recurring and unpredictable problem starting dnf.

dnf will display no output for a number of minutes and then exit with an error like (not always this)

Error: Failed to synchronize cache for repo 'qubes-vm-r3.2-current'

or

Error: Failed to synchronize cache for repo 'fedora'

I have the issue about 50% of the time I try to use dnf on a TemplateVM. If the error appears, I usually attempt to troubleshoot for 20 mins before it randomly works, or I give up and decide to try later.

Some symptoms/findings:

- An AppVM based on the TemplateVM may be able to use dnf at the same time the TemplateVM cannot
- Internet access (ie web browsing) is never affected
- Allowing all internet access to the TemplateVM usually does not fix the problem
- Allowing all internet access and turning off proxy updates usually does not fix the problem
- Resetting the TemplateVM usually does not fix the problem
- Resetting sys-firewall usually does not fix the problem
- Changing the TemplateVM behind sys-firewall usually does not fix the problem
- Adding fastestmirror=true to dnf.conf does not fix the problem
- Restarting Qubes sometimes fixes the problem

I'm using fedora-25 and fedora-25-minimal as my core distributions.

Has anyone else come across this problem?

[Nemo]

I've been able to isolate one issue:

A NetVM running a Fedora minimal distribution (including the NetVM packages) will not allow for updates by via qubes-update-proxy from TemplateVMs.

[Nemo]

This problem was caused by tinyproxy not installing as I set up fedora-24-minimal for NetVM usage.

From https://groups.google.com/forum/#!topic/qubes-users/sR7Z5KkL5NQ :

> The package qubes-template-minimal-stub prevent the install of tinyproxy.
>
> In order to do that, you have to install with the full package name:
>
> sudo dnf install tinyproxy.x86_64

I've submitted an update request for the Fedora Minimal documentation to include this.

https://www.qubes-os.org/doc/templates/fedora-minimal/

[mil...@gmail.com]

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MAY YOUR GOD RAIN BLESSINGS UPON YOUR SOUL

I had this same maddening issue. I was also able to figure out that it just stopped working when I switched sys-net from fedora-23 to fedora-25-net (my minimal version).

If you don't mind my asking, how were you able to figure out that tinyproxy was not installed correctly?

I'd gone through the services tabs but idk what I would have done next... I found your solution on here and it worked!

Also, this is not in the documentation yet! How do we put it there? Doesn't need to be in the minimal-template one but it should be in the Fedora-24 to 25 one I think.