hostname in chroot

[Michael DiDomenico]

i have a series of playbooks that use ansible_hostname to determine whether tasks should run.  on a host these work fine as one would expect, but when running ansible inside a chroot environment with /proc,sys,dev mounted.  ansible pulls the hostname from the host outside of the chroot into ansible_hostname,ansible_fqdn,ansible_nodename variables

is there a reliable way to tell ansible, this is what the hostname name regardless outside factors?

i tried settings facts to override the three variables or tricking it through the inventory, but 'ansible -m setup localhost' inside the chroot always seems to grab the hostname from outside the chroot

i'm likely doing something wrong, but i'm not sure what

thanks

[Michael DiDomenico]

for what it's worth i figured out a solution to this using namespaces.  i'll leave the full script upto the reader, but maybe this will help someone later

unshare --uts=<file> chroot <rootdir> /bin/bash

once in the new namespace, you can change the hostname and it does not affect the base system, which i verified with

- hostname outside the chroot

hosta

- inside the chroot

ansible -m setup localhost | egrep "hostname|nodename|fqdn"

ansible_hostname = "hostb"

ansible_fqdn = "hostb"

ansible_nodename = "hostb"