Cannot unassign a site from a vlan

[candlerb]

Environment

• Python version: 3.6.9
• NetBox version: 2.9.8

Steps to Reproduce

1. Create a VLAN, say ID "123" name "foo" and save. (No site assigned)
2. Edit the VLAN. Set the site to some existing site, and save.
3. Edit the VLAN. Set the site to "None" and save.

Expected Behavior

To be able to set the site to "None"

Observed Behavior

After selecting "None" and clicking Save, the update is rejected:

[jeremystretch]

I tried several times but haven't been able to reproduce this on v2.9.8. On step three, the VLAN saves as expected with no site assigned.

[candlerb]

Weird.

root@netbox:/opt/netbox# git status
On branch master
Your branch is up to date with 'origin/master'.

nothing to commit, working tree clean
root@netbox:/opt/netbox# git show
commit 6dcb2de28f65c4907332ede49430f64b3aff1d18 (HEAD -> master, tag: v2.9.8, origin/master)
Merge: 1bbfc6da cbd15540
Author: Jeremy Stretch <jeremy.stretch@networktocode.com>
Date:   Fri Oct 30 10:38:17 2020 -0400

    Merge pull request #5293 from netbox-community/develop

    Release v2.9.8

I have restarted Netbox - no difference.

The message "Select a valid choice" seems to be in the django source, but the packages match requirements.txt:

root@netbox:/opt/netbox# . venv/bin/activate
(venv) root@netbox:/opt/netbox# pip3 list | grep -i django
DEPRECATION: The default format will switch to columns in the future. You can use --format=(legacy|columns) (or define a format=(legacy|columns) in your pip.conf under the [list] section) to disable this warning.
Django (3.1)
django-cacheops (5.1)
django-cors-headers (3.4.0)
django-debug-toolbar (2.2)
django-filter (2.3.0)
django-js-asset (1.2.2)
django-mptt (0.11.0)
django-pglocks (1.0.4)
django-prometheus (2.0.0)
django-rq (2.3.2)
django-tables2 (2.3.1)
django-taggit (1.3.0)
django-timezone-field (4.0)
djangorestframework (3.11.0)

[jeremystretch]

Do you maybe have a VLAN group or site region in play? Not sure that it would matter.

[candlerb]

I note that the word "None" rather than "---" appears in the dropdown: do you see the same?

The HTML is:

<ul class="select2-results__options" role="listbox" id="select2-id_site-results" aria-expanded="true" aria-hidden="false">
  <li class="select2-results__option select2-results__option--highlighted" role="option" aria-selected="false" data-select2-id="17">None</li>
  <li class="select2-results__option" role="option" aria-selected="false" data-select2-id="18">Main Site</li>
  <li class="select2-results__option" role="option" aria-selected="false" data-select2-id="19">Test Site</li>
</ul>

I don't know what data-select2-id values represent. These aren't the ids of the sites:

netbox=# select id, name from dcim_site;
 id |   name
----+-----------
  7 | Test Site
  1 | Main Site
(2 rows)

[candlerb]

Do you maybe have a VLAN group or site region in play? Not sure that it would matter.

No vlan groups, but one of the sites ("Main Site") is in a region.

[candlerb]

I've removed the site from a region.

However I've now noticed there are two different things. There's the "X" next to the site, and there's selecting site "None".

Clicking the "X" gives:

As long as I don't click None, but instead click outside of the whole drop-down, I get:

And now I can save successfully. It seems the "None" option in the dropdown is spurious.

[jeremystretch]

Aha, yeah that's it. I had none selected, rather than selecting None. 😄

We can probably just get rid of the explicit "None" option.

[jeremystretch]

We have a bit of a problem in that the site field in this case is used for two things:

1. Assigning the VLAN to a site
2. Restricting the option returned when selecting a VLAN group

Currently, if the site field is left deselected, the group field will list all available VLAN groups. If the site is set to "None," it will return only VLAN groups which belong to that site (although VLAN creation will ultimately fail as described above).

If we simply remove the "None" option, it becomes impossible to filter VLAN groups by site. This same pattern is present elsewhere in NetBox, too.

[candlerb]

Interesting. If you could make selecting the explicit "None" option work as a choice, that would be fine.

There's a secondary reported problem there which I haven't ticketed yet. It's to do with prefixes.

As I understand it: if you set a Site on a prefix, then choose a VLAN, it only offers you the VLANs linked to that site (not global VLANs). But If you select the VLAN first, then select a Site, you can choose a global VLAN and it's accepted.