[yocto] bitbake error ?

[Riko]

Dear Yocto Member,


I have downloaded fresh install of yocto but got error, here's the trace :

bianchi at bianchi-HP-Pavilion-dv6-Notebook-PC:~$ git clone -b pyro 
git://git.yoctoproject.org/poky.git
Cloning into 'poky'...
remote: Counting objects: 373183, done.
remote: Compressing objects: 100% (89366/89366), done.
remote: Total 373183 (delta 277418), reused 373031 (delta 277266)
Receiving objects: 100% (373183/373183), 134.71 MiB | 1.47 MiB/s, done.
Resolving deltas: 100% (277418/277418), done.
Checking connectivity... done.


bianchi at bianchi-HP-Pavilion-dv6-Notebook-PC:~/poky$ source oe-init-build-env
You had no conf/local.conf file. This configuration file has therefore been
created for you with some default values. You may wish to edit it to, for
example, select a different MACHINE (target hardware). See conf/local.conf
for more information as common configuration options are commented.

You had no conf/bblayers.conf file. This configuration file has 
therefore been
created for you with some default values. To add additional metadata layers
into your configuration please add entries to conf/bblayers.conf.

The Yocto Project has extensive documentation about OE including a reference
manual which can be found at:
     http://yoctoproject.org/documentation

For more information about OpenEmbedded see their website:
     http://www.openembedded.org/


### Shell environment set up for builds. ###

You can now run 'bitbake <target>'

Common targets are:
     core-image-minimal
     core-image-sato
     meta-toolchain
     meta-ide-support

You can also run generated qemu images with a command like 'runqemu qemux86'
bianchi at bianchi-HP-Pavilion-dv6-Notebook-PC:~/poky/build$ bitbake 
core-image-minimal
ERROR:  OE-core's config sanity checker detected a potential 
misconfiguration.
     Either fix the cause of this error or at your own risk disable the 
checker (see sanity.conf).
     Following is the list of potential problems / advisories:

     Fetcher failure for URL: 'https://www.example.com/'. URL 
https://www.example.com/ doesn't work.
     Please ensure your host's network is configured correctly,
     or set BB_NO_NETWORK = "1" to disable network access if
     all required sources are on local disk.


Summary: There was 1 ERROR message shown, returning a non-zero exit code.


Any suggestions ?

I'm using ubuntu 16.04,

Thanks