yahoo-eng-team team mailing list archive

[Sabari Murugesan <1712440@xxxxxxxxxxxxxxxxxx>]

Public bug reported:

Cloud Provider: OpenStack (Mitaka)
Distro: Ubuntu 16.04
Cloud-init version: 0.7.9 (cloud-init cfg is distro provider)

Other Info:
Nova Instance booted with Config Drive on a Neutron Network (without DHCP)

Problem:
when a nova instance is booted with config drive on a network with DHCP disabled, the global DNS servers passed in the network_data.json are not rendered to the eth0 interface in the /etc/network/interface.d/50-cloud-init.cfg file. It is only available on the 'lo' interface. As a result, /etc/resolv.conf is empty and all name resolutions fail.

/etc/network/interface.d/50-cloud-init.cfg looks like this
auto lo
iface lo inet loopback
    dns-nameservers 8.8.8.8

auto eth0
iface eth0 inet static
    address 192.168.111.183
    netmask 255.255.255.0
    post-up route add default gw 192.168.111.1 || true
    pre-down route del default gw 192.168.111.1 || true

instead, IMO, it should probably look like this:-

auto lo
iface lo inet loopback
    dns-nameservers 8.8.8.8

auto eth0
iface eth0 inet static
    address 192.168.111.183
    dns-nameservers 8.8.8.8 // Notice this additional dns info in eth0
    netmask 255.255.255.0
    post-up route add default gw 192.168.111.1 || true
    pre-down route del default gw 192.168.111.1 || true

I tried the fix in bug 1693265 i.e https://review.openstack.org/#/c/467699/ but it
still didn't add the dns-nameservers in the eth0 of the ENI file.

Then, I tried a custom fix (attached nova.diff) to pass the dns_namesevers
in the "networks" value of the network_data.json and that seems to fix the problem for me.

At this point, I am not clear if this is a bug in Nova or Cloud-Init to
render the dns servers in ENI file correctly. Please let me know if you
need more info.

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

** Attachment added: "nova.diff"
   https://bugs.launchpad.net/bugs/1712440/+attachment/4937249/+files/nova.diff

** Description changed:

- 
  Cloud Provider: OpenStack (Mitaka)
- Distro: Ubuntu 16.04 
+ Distro: Ubuntu 16.04
  Cloud-init version: 0.7.9 (cloud-init cfg is distro provider)
  
  Other Info:
  Nova Instance booted with Config Drive on a Neutron Network (without DHCP)
  
- Problem: 
- when a nova instance is booted with config drive on a network with DHCP disabled,
- the global DNS servers passed in the network_data.json are not rendered to the
- eth0 interface in the /etc/network/interface.d/50-cloud-init.cfg file. It is only
- available on the 'lo' interface. As a result, /etc/resolv.conf is empty. 
+ Problem:
+ when a nova instance is booted with config drive on a network with DHCP disabled, the global DNS servers passed in the network_data.json are not rendered to the eth0 interface in the /etc/network/interface.d/50-cloud-init.cfg file. It is only available on the 'lo' interface. As a result, /etc/resolv.conf is empty.
  
  /etc/network/interface.d/50-cloud-init.cfg looks like this
  auto lo
  iface lo inet loopback
-     dns-nameservers 8.8.8.8
+     dns-nameservers 8.8.8.8
  
  auto eth0
  iface eth0 inet static
-     address 192.168.111.183
-     netmask 255.255.255.0
-     post-up route add default gw 192.168.111.1 || true
-     pre-down route del default gw 192.168.111.1 || true
- 
+     address 192.168.111.183
+     netmask 255.255.255.0
+     post-up route add default gw 192.168.111.1 || true
+     pre-down route del default gw 192.168.111.1 || true
  
  instead, IMO, it should probably look like this:-
  
  auto lo
  iface lo inet loopback
-     dns-nameservers 8.8.8.8
+     dns-nameservers 8.8.8.8
  
  auto eth0
  iface eth0 inet static
-     address 192.168.111.183
-     dns-nameservers 8.8.8.8 // Notice this additional dns info in eth0
-     netmask 255.255.255.0
-     post-up route add default gw 192.168.111.1 || true
-     pre-down route del default gw 192.168.111.1 || true
- 
+     address 192.168.111.183
+     dns-nameservers 8.8.8.8 // Notice this additional dns info in eth0
+     netmask 255.255.255.0
+     post-up route add default gw 192.168.111.1 || true
+     pre-down route del default gw 192.168.111.1 || true
  
  I tried the fix in bug 1693265 i.e https://review.openstack.org/#/c/467699/ but it
  still didn't add the dns-nameservers in the eth0 of the ENI file.
  
  Then, I tried a custom fix (attached nova.diff) to pass the dns_namesevers
- in the "networks" value of the network_data.json and that seems to fix the problem
- for me.
+ in the "networks" value of the network_data.json and that seems to fix the problem for me.
  
- At this point, I am not clear if this is a bug in Nova or Cloud-Init to render
- the dns servers in ENI file correctly. Please let me know if you need more info.
+ At this point, I am not clear if this is a bug in Nova or Cloud-Init to
+ render the dns servers in ENI file correctly. Please let me know if you
+ need more info.

** Description changed:

  Cloud Provider: OpenStack (Mitaka)
  Distro: Ubuntu 16.04
  Cloud-init version: 0.7.9 (cloud-init cfg is distro provider)
  
  Other Info:
  Nova Instance booted with Config Drive on a Neutron Network (without DHCP)
  
  Problem:
- when a nova instance is booted with config drive on a network with DHCP disabled, the global DNS servers passed in the network_data.json are not rendered to the eth0 interface in the /etc/network/interface.d/50-cloud-init.cfg file. It is only available on the 'lo' interface. As a result, /etc/resolv.conf is empty.
+ when a nova instance is booted with config drive on a network with DHCP disabled, the global DNS servers passed in the network_data.json are not rendered to the eth0 interface in the /etc/network/interface.d/50-cloud-init.cfg file. It is only available on the 'lo' interface. As a result, /etc/resolv.conf is empty and all name resolutions fail.
  
  /etc/network/interface.d/50-cloud-init.cfg looks like this
  auto lo
  iface lo inet loopback
      dns-nameservers 8.8.8.8
  
  auto eth0
  iface eth0 inet static
      address 192.168.111.183
      netmask 255.255.255.0
      post-up route add default gw 192.168.111.1 || true
      pre-down route del default gw 192.168.111.1 || true
  
  instead, IMO, it should probably look like this:-
  
  auto lo
  iface lo inet loopback
      dns-nameservers 8.8.8.8
  
  auto eth0
  iface eth0 inet static
      address 192.168.111.183
      dns-nameservers 8.8.8.8 // Notice this additional dns info in eth0
      netmask 255.255.255.0
      post-up route add default gw 192.168.111.1 || true
      pre-down route del default gw 192.168.111.1 || true
  
  I tried the fix in bug 1693265 i.e https://review.openstack.org/#/c/467699/ but it
  still didn't add the dns-nameservers in the eth0 of the ENI file.
  
  Then, I tried a custom fix (attached nova.diff) to pass the dns_namesevers
  in the "networks" value of the network_data.json and that seems to fix the problem for me.
  
  At this point, I am not clear if this is a bug in Nova or Cloud-Init to
  render the dns servers in ENI file correctly. Please let me know if you
  need more info.

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https://bugs.launchpad.net/bugs/1712440

Title:
  Missing dns-nameservers in eth0 with config drive on openstack
  instance

Status in cloud-init:
  New

Bug description:
  Cloud Provider: OpenStack (Mitaka)
  Distro: Ubuntu 16.04
  Cloud-init version: 0.7.9 (cloud-init cfg is distro provider)

  Other Info:
  Nova Instance booted with Config Drive on a Neutron Network (without DHCP)

  Problem:
  when a nova instance is booted with config drive on a network with DHCP disabled, the global DNS servers passed in the network_data.json are not rendered to the eth0 interface in the /etc/network/interface.d/50-cloud-init.cfg file. It is only available on the 'lo' interface. As a result, /etc/resolv.conf is empty and all name resolutions fail.

  /etc/network/interface.d/50-cloud-init.cfg looks like this
  auto lo
  iface lo inet loopback
      dns-nameservers 8.8.8.8

  auto eth0
  iface eth0 inet static
      address 192.168.111.183
      netmask 255.255.255.0
      post-up route add default gw 192.168.111.1 || true
      pre-down route del default gw 192.168.111.1 || true

  instead, IMO, it should probably look like this:-

  auto lo
  iface lo inet loopback
      dns-nameservers 8.8.8.8

  auto eth0
  iface eth0 inet static
      address 192.168.111.183
      dns-nameservers 8.8.8.8 // Notice this additional dns info in eth0
      netmask 255.255.255.0
      post-up route add default gw 192.168.111.1 || true
      pre-down route del default gw 192.168.111.1 || true

  I tried the fix in bug 1693265 i.e https://review.openstack.org/#/c/467699/ but it
  still didn't add the dns-nameservers in the eth0 of the ENI file.

  Then, I tried a custom fix (attached nova.diff) to pass the dns_namesevers
  in the "networks" value of the network_data.json and that seems to fix the problem for me.

  At this point, I am not clear if this is a bug in Nova or Cloud-Init
  to render the dns servers in ENI file correctly. Please let me know if
  you need more info.

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