Centos network manager on Centos 7.2 revert settings from /etc/hosts and /etc/resolv.conf

https://community.centminmod.com/posts/20091/

and

Stop DHCP From Changing resolv.conf - Vultr.com

 

who's the web host ? what virtualisation ? xen, openvz, kvm, vmware ?

could be elated to cloud.cfg on some virtual machines not sure
i.e. on Vultr /etc/cloud/cloud.cfg

Code:

users:
- default

disable_root: 1
ssh_pwauth:   0

locale_configfile: /etc/sysconfig/i18n
mount_default_fields: [~, ~, 'auto', 'defaults,nofail', '0', '2']
resize_rootfs_tmp: /dev
ssh_deletekeys:   0
ssh_genkeytypes:  ~
syslog_fix_perms: ~

cloud_init_modules:
- migrator
- bootcmd
- write-files
- growpart
- resizefs
- set_hostname
- update_hostname
- update_etc_hosts
- rsyslog
- users-groups
- ssh

cloud_config_modules:
- mounts
- locale
- set-passwords
- yum-add-repo
- package-update-upgrade-install
- timezone
- puppet
- chef
- salt-minion
- mcollective
- disable-ec2-metadata
- runcmd

cloud_final_modules:
- rightscale_userdata
- scripts-per-once
- scripts-per-boot
- scripts-per-instance
- scripts-user
- ssh-authkey-fingerprints
- keys-to-console
- phone-home
- final-message

system_info:
  default_user:
    name: centos
    lock_passwd: true
    gecos: Cloud User
    groups: [wheel, adm, systemd-journal]
    sudo: ["ALL=(ALL) NOPASSWD:ALL"]
    shell: /bin/bash
  distro: rhel
  paths:
    cloud_dir: /var/lib/cloud
    templates_dir: /etc/cloud/templates
  ssh_svcname: sshd

# vim:syntax=yaml

Code:

ls -lahR /etc/cloud/
/etc/cloud/:
total 28K
drwxr-xr-x  4 root root 4.0K Aug 10 14:04 .
drwxr-xr-x 92 root root  12K Feb  4 16:45 ..
-rw-rw-r--  1 root root 1.2K Jul 29  2014 cloud.cfg
drwxr-xr-x  2 root root 4.0K Aug 10 14:04 cloud.cfg.d
drwxr-xr-x  2 root root 4.0K Aug 10 14:04 templates

/etc/cloud/cloud.cfg.d:
total 20K
drwxr-xr-x 2 root root 4.0K Aug 10 14:04 .
drwxr-xr-x 4 root root 4.0K Aug 10 14:04 ..
-rw-r--r-- 1 root root 1.9K Apr  1  2014 05_logging.cfg
-rw-r--r-- 1 root root  679 Aug 10 14:04 90_vultr.cfg
-rw-r--r-- 1 root root  141 Apr  1  2014 README

/etc/cloud/templates:
total 36K
drwxr-xr-x 2 root root 4.0K Aug 10 14:04 .
drwxr-xr-x 4 root root 4.0K Aug 10 14:04 ..
-rw-r--r-- 1 root root  892 Apr  1  2014 chef_client.rb.tmpl
-rw-r--r-- 1 root root  934 Apr  1  2014 hosts.debian.tmpl
-rw-r--r-- 1 root root  906 Apr  1  2014 hosts.redhat.tmpl
-rw-r--r-- 1 root root  862 Apr  1  2014 hosts.suse.tmpl
-rw-r--r-- 1 root root  785 Apr  1  2014 resolv.conf.tmpl
-rw-r--r-- 1 root root 1.5K Apr  1  2014 sources.list.debian.tmpl
-rw-r--r-- 1 root root 2.8K Apr  1  2014 sources.list.ubuntu.tmpl

from /etc/cloud/templates/hosts.redhat.tmpl

Code:

#*
    This file /etc/cloud/templates/hosts.redhat.tmpl is only utilized
    if enabled in cloud-config.  Specifically, in order to enable it
    you need to add the following to config:
      manage_etc_hosts: True
*#
# Your system has configured 'manage_etc_hosts' as True.
# As a result, if you wish for changes to this file to persist
# then you will need to either
# a.) make changes to the master file in /etc/cloud/templates/hosts.redhat.tmpl
# b.) change or remove the value of 'manage_etc_hosts' in
#     /etc/cloud/cloud.cfg or cloud-config from user-data
#
# The following lines are desirable for IPv4 capable hosts
127.0.0.1 ${fqdn} ${hostname}
127.0.0.1 localhost.localdomain localhost
127.0.0.1 localhost4.localdomain4 localhost4

# The following lines are desirable for IPv6 capable hosts
::1 ${fqdn} ${hostname}
::1 localhost.localdomain localhost
::1 localhost6.localdomain6 localhost6

so you could add your custom /etc/hosts entry into template at /etc/cloud/templates/hosts.redhat.tmpl

for /etc/resolv.conf and /etc/cloud/templates/resolv.conf.tmpl

Code:

#
# Your system has been configured with 'manage-resolv-conf' set to true.
# As a result, cloud-init has written this file with configuration data
# that it has been provided. Cloud-init, by default, will write this file
# a single time (PER_ONCE).
#

#if $varExists('nameservers')
#for $server in $nameservers
nameserver $server
#end for
#end if
#if $varExists('searchdomains')
search #slurp
#for $search in $searchdomains
$search #slurp
#end for

#end if
#if $varExists('domain')
domain $domain
#end if
#if $varExists('sortlist')
sortlist #slurp
#for $sort in $sortlist
$sort #slurp
#end for

#end if
#if $varExists('options') or $varExists('flags')
options #slurp
#for $flag in $flags
$flag #slurp
#end for
#for $key, $value in $options.items()
$key:$value #slurp
#end for

#end if