yahoo-eng-team team mailing list archive

[Steven Edgar <launchpad.net@xxxxxxxxxx>]

Public bug reported:

I'm running the latest RHEL AMI in AWS, listed as

Red Hat Enterprise Linux 7.4 (HVM), SSD Volume Type - ami-bb9a6bc2

(ID is from the Ireland region).

For a variety of reasons I need to set a different domain on this server
than that set in the DHCP option set for the VPC. Changing the option
set isn't an option, and neither is creating a separate VPC, for
organisational reasons. I need the resolv.conf to contain the line

domain subdomain.example.com

although changing the search line would also appear to be sufficient for
my purposes.

Now resolv.conf is managed by NetworkManager, so I could simply alter
/etc/sysconfig/network-scripts/ifcfg-eth0 to add in the DOMAIN= line,
but that file appears to be managed by cloud-init. What I've been unable
to manage is getting cloud-init to add the DOMAIN= line to that file
when it regenerates it.

I originally saw this in our custom AMI, which uses RHEL 7.3, but have
just verified it in a new EC2 instance started up using the latest AWS
provided RHEL 7 AMI. I have also attempted the same configuration using
the latest Amazon Linux AMI with identical results. I have to state here
that I'm not 100% sure I'm using the correct configuration here, not
being that familiar with cloud-init, however a chat on the cloud-init
IRC channel indicated the configuration in use isn't obviously
incorrect.

In all cases, the ifcfg-eth0 and resolv.conf files are unchanged by the
cloud-init settings I've added, and I can find no reference to string
'subdomain.example.com' anywhere under /etc

Note, I've had to edit the attached files to blank the IP addresses and
change the domain to example.com due to organisational security rules.


$ uname -a
Linux ip-XXX-XXX-XXX-XXX.example.com 3.10.0-693.el7.x86_64 #1 SMP Thu Jul 6 19:56:57 EDT 2017 x86_64 x86_64 x86_64 GNU/Linux

$ cat /etc/redhat-release 
Red Hat Enterprise Linux Server release 7.4 (Maipo)

$ cloud-init -v
cloud-init 0.7.9

$ cat /etc/cloud/cloud.cfg
users:
 - default

disable_root: 1
ssh_pwauth:   0

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
 - rh_subscription
 - 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
 - power-state-change

system_info:
  default_user:
    name: ec2-user
    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

manage_resolv_conf: true

resolv_conf:
  searchdomains:
    - subdomain.example.com
  domain: subdomain.example.com


=========================================
Amazon Linux AMI 2017.03.1 (HVM), SSD Volume Type - ami-ebd02392

$ cloud-init -v
cloud-init 0.7.6

$ cat /etc/cloud/cloud.cfg
# WARNING: Modifications to this file may be overridden by files in
# /etc/cloud/cloud.cfg.d

# If this is set, 'root' will not be able to ssh in and they 
# will get a message to login instead as the default user (ec2-user)
disable_root: true

# This will cause the set+update hostname module to not operate (if true)
preserve_hostname: true

datasource_list: [ Ec2, None ]

repo_upgrade: security
repo_upgrade_exclude:
 - kernel
 - nvidia*
 - cudatoolkit

mounts:
 - [ ephemeral0, /media/ephemeral0 ]
 - [ swap, none, swap, sw, "0", "0" ]
# vim:syntax=yaml

manage_resolv_conf: true

resolv_conf:
  searchdomains:
    - subdomain.example.com
  domain: subdomain.example.com

** Affects: cloud-init
     Importance: Undecided
         Status: New

** Attachment added: "cloud-init.tar"
   https://bugs.launchpad.net/bugs/1712764/+attachment/4937883/+files/cloud-init.tar

-- 
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to cloud-init.
https://bugs.launchpad.net/bugs/1712764

Title:
  Unable to set domain or search options in resolv.conf on RHEL 7

Status in cloud-init:
  New

Bug description:
  I'm running the latest RHEL AMI in AWS, listed as

  Red Hat Enterprise Linux 7.4 (HVM), SSD Volume Type - ami-bb9a6bc2

  (ID is from the Ireland region).

  For a variety of reasons I need to set a different domain on this
  server than that set in the DHCP option set for the VPC. Changing the
  option set isn't an option, and neither is creating a separate VPC,
  for organisational reasons. I need the resolv.conf to contain the line

  domain subdomain.example.com

  although changing the search line would also appear to be sufficient
  for my purposes.

  Now resolv.conf is managed by NetworkManager, so I could simply alter
  /etc/sysconfig/network-scripts/ifcfg-eth0 to add in the DOMAIN= line,
  but that file appears to be managed by cloud-init. What I've been
  unable to manage is getting cloud-init to add the DOMAIN= line to that
  file when it regenerates it.

  I originally saw this in our custom AMI, which uses RHEL 7.3, but have
  just verified it in a new EC2 instance started up using the latest AWS
  provided RHEL 7 AMI. I have also attempted the same configuration
  using the latest Amazon Linux AMI with identical results. I have to
  state here that I'm not 100% sure I'm using the correct configuration
  here, not being that familiar with cloud-init, however a chat on the
  cloud-init IRC channel indicated the configuration in use isn't
  obviously incorrect.

  In all cases, the ifcfg-eth0 and resolv.conf files are unchanged by
  the cloud-init settings I've added, and I can find no reference to
  string 'subdomain.example.com' anywhere under /etc

  Note, I've had to edit the attached files to blank the IP addresses
  and change the domain to example.com due to organisational security
  rules.

  
  $ uname -a
  Linux ip-XXX-XXX-XXX-XXX.example.com 3.10.0-693.el7.x86_64 #1 SMP Thu Jul 6 19:56:57 EDT 2017 x86_64 x86_64 x86_64 GNU/Linux

  $ cat /etc/redhat-release 
  Red Hat Enterprise Linux Server release 7.4 (Maipo)

  $ cloud-init -v
  cloud-init 0.7.9

  $ cat /etc/cloud/cloud.cfg
  users:
   - default

  disable_root: 1
  ssh_pwauth:   0

  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
   - rh_subscription
   - 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
   - power-state-change

  system_info:
    default_user:
      name: ec2-user
      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

  manage_resolv_conf: true

  resolv_conf:
    searchdomains:
      - subdomain.example.com
    domain: subdomain.example.com

  
  =========================================
  Amazon Linux AMI 2017.03.1 (HVM), SSD Volume Type - ami-ebd02392

  $ cloud-init -v
  cloud-init 0.7.6

  $ cat /etc/cloud/cloud.cfg
  # WARNING: Modifications to this file may be overridden by files in
  # /etc/cloud/cloud.cfg.d

  # If this is set, 'root' will not be able to ssh in and they 
  # will get a message to login instead as the default user (ec2-user)
  disable_root: true

  # This will cause the set+update hostname module to not operate (if true)
  preserve_hostname: true

  datasource_list: [ Ec2, None ]

  repo_upgrade: security
  repo_upgrade_exclude:
   - kernel
   - nvidia*
   - cudatoolkit

  mounts:
   - [ ephemeral0, /media/ephemeral0 ]
   - [ swap, none, swap, sw, "0", "0" ]
  # vim:syntax=yaml

  manage_resolv_conf: true

  resolv_conf:
    searchdomains:
      - subdomain.example.com
    domain: subdomain.example.com

To manage notifications about this bug go to:
https://bugs.launchpad.net/cloud-init/+bug/1712764/+subscriptions