Quick Fix for Useless Salt Warning – Add "file_ignore_glob: []" to /etc/salt/master

Some versions of Salt give you a useless warning on every run. The problem is easy to fix.

To get rid of useless “[WARNING ] Key ‘file_ignore_glob’ with value None..”.
Add ”file_ignore_glob: []” to /etc/salt/master.

Bug

Useless warnings on every salt run:

$ sudo salt '*' test.ping
[WARNING ] Key 'file_ignore_glob' with value None has an invalid type of NoneType, a list is required for this value
[WARNING ] Key 'file_ignore_glob' with value None has an invalid type of NoneType, a list is required for this value
[WARNING ] Key 'file_ignore_glob' with value None has an invalid type of NoneType, a list is required for this value
[WARNING ] Key 'file_ignore_glob' with value None has an invalid type of NoneType, a list is required for this value
tero:
 True

The problem is present in the salt-master version Beryllium, which is included with Ubuntu (and Xubuntu) 16.04 LTS. The bug is fixed in latest versions of Salt.

$ grep DESC /etc/lsb-release
DISTRIB_DESCRIPTION="Ubuntu 16.04.3 LTS"
$ salt-master --version
salt-master 2015.8.8 (Beryllium)

Fix

$ sudoedit /etc/salt/master

By default, the file contains zero non-comment lines. Anyway, add

file_ignore_glob: []

Solved

$ sudo salt '*' test.ping
tero:
 True

The useless warning is gone.
Update: This article has been edited multiple times.