View Issue Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0015833||CentOS-7||cloud-init||public||2019-02-15 23:59||2019-11-20 19:44|
|Target Version||Fixed in Version|
|Summary||0015833: ipv6 router advertisements are disabled due to IPV6_AUTOCONF=no|
|Description||I tested this with an Amazon VPC with working IPv6 configuration (the amazon-ami's work fine) using cloud-init 18.2_1.|
If one assigns an IPv6 address to the machine via DHCP6. Cloudinit sets up a configuration that apparently disables router advertisements due to side-effect. As a result the box has no default gateway and is unable to send IPv6 traffic (Network unreachable errors).
I found someone else mentioning this issue here and their work-around: https://access.redhat.com/solutions/347693#comment-520173
And it basically came down to having IPV6_AUTOCONF=no which sets the sysctl setting, net.ipv6.conf.eth0.accept_ra=0. Disabling router advertisements.
Overriding IPV6_AUTOCONF in /etc/sysconfig/network-scripts to yes enables the seemingly correct functionality. This appears to be set by cloud-init in /usr/lib/python2.7/site-packages/cloudinit/net/sysconfig.py.
|Steps To Reproduce||1. Verify ipv6 ip: `ip a show dev eth0`|
2. Verify no default route: `ip -6 r show dev eth0`
3. Verify ping fails: `ping6 -c1 ipv6.google.com`
4. Set IPV6_AUTOCONF=yes in /etc/sysconfig/network-scripts
5. Restart networking: `sudo systemctl restart network`
6. Verify default route: `ip -6 r show dev eth0 | grep default`
7. Verify ping succeeds: `ping6 -c1 ipv6.google.com`
|Tags||cloud-init, IPv6, network|
I have also came across this issue in Amazon AWS with the official CentOS 7 image, but in my case the file to edit is /etc/sysconfig/network and must manually change to IPV6_AUTOCONF=yes
I have also tried to simply add a script to /etc/cloud/cloud.cfg.d/99-net-ipv6.cfg
- type: physical
- type: dhcp
- type: dhcp6
just by adding the script mand rebooting it doesn't work. I had to go manually and edit /etc/sysconfig/network setting ipv6_autoconf to yes and has been persisting...
|Meanwhile I just verified on cloud-init bug tracker the fix has been committed 1 hour ago...|
|2019-02-15 23:59||dekimsey||New Issue|
|2019-02-15 23:59||dekimsey||Tag Attached: cloud-init|
|2019-02-15 23:59||dekimsey||Tag Attached: IPv6|
|2019-02-15 23:59||dekimsey||Tag Attached: network|
|2019-11-20 19:27||maverickws||Note Added: 0035717|
|2019-11-20 19:44||maverickws||Note Added: 0035718|