hostname cannot resolved during installation of IBM private cloud ce - ibm-cloud-private

Question

I installed IBM-Cloud-private-ce by following the guide https://www.ibm.com/support/knowledgecenter/SSBS6K_1.2.0/installing/install_containers_CE.html
But after I ran docker run -e LICENSE=accept --net=host -t -v "$(pwd)":/installer/cluster ibmcom/cfc-installer:1.2.0 install, I got the following error messages
task path: /installer/playbook/roles/check/tasks/main.yaml:78
fatal: [a.b.c.d] => Hostname should be resolved to a valid IP address
fatal: [a.b.c.e] => Hostname should be resolved to a valid IP address
I put the ip address as [a.b.c.d] just for confidential. Actually they are numbers here. These IP address are reachable.
By checking the ansible file, I noticed the following code
- name: Checking Hostname is resolvable
shell: ping -c 1 $(hostname) | awk -F'[()]' '{print $2;exit}'
args:
executable: /bin/bash
register: ip_out
- name: Validating Hostname is resolvable
fail: msg="Hostname should be resolved to a valid IP address"
when: ip_out.stdout in ['', '127.0.0.1', '127.0.1.1']
I found I cannot ping in the container as the image hasn't ping in it.
Is this the reason why I got the message? I appreciate if anyone could help on it.
Updated the question. Thanks #SBERENS
I tried on the 2.1.0 version and met the same issue: (for confidential reason, I used a.b.c.d as the IP address, actually the IP address are reachable)
My /etc/hosts is like the following:
127.0.0.1 localhost
127.0.1.1 e1.xx.yy.com e1
# The following lines are desirable for IPv6 capable hosts
::1 localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
#puppet:
a.b.c.a puppet.xx.yy.com puppet
a.b.c.d e1.xx.yy.com e1
a.b.c.e e2.xx.yy.com e2
The cluster/hosts is like:
[master]
a.b.c.d
[worker]
a.b.c.e
[proxy]
a.b.c.e
#[management]
#4.4.4.4

Answer 1

The link you posted seems to be for older 1.2 level.
Please check that you are following the correct most updated installation instructions.
Latest version ICP 2.1 - CE are here:
https://www.ibm.com/support/knowledgecenter/SSBS6K_2.1.0/installing/install_ce.html
Can you please post your /etc/hosts file and the cluster/hosts file contents?

Answer 2

Your issue will occur in either 1.2 or 2.1.
The error is that the hostname e1.xx.yy.com resolves to a.b.c.d and 127.0.1.1. When this happens, the installer is enforcing the resolved IP to be something which is externally routable.
Is there a reason why you have the machine hostname defined on the local address in addition to a separate network IP?

Answer 3

Suggest removal of the line:
127.0.1.1 e1.xx.yy.com e1
from /etc/hosts. This can cause DNS confusion esp on Ubuntu.