Re: NetworkManager recycling connections

[Jirka Klimes <jklimes redhat com>]

On Tuesday 15 of November 2011 20:56:41 Bill C Riemers wrote:
> I found the problem.  I was wrong about needing to toggle the flag after
> every boot.
> 
> Here is the problem, network manager is using the IPV6INIT=no flag, as the
> flag IPV6 - IGNORE on a device.   But it looks like to me that flag only
> controls the use of DHCPv6.   Since DHCPv6 is not required when using
> Router Advertisements, with "IPV6INIT=no" my wifi comes up successfully
> with an IPv6 configuration.   If I use IPV6INIT=yes, then it also comes up
> successfully, but it waits around for a DHCPv6 that does not exist.  After
> about 15-20 minutes that times out so it recycles the working connection.
> 
IPV6INIT (together with other flags flags) is used to read/write IPv6 methods 
via ifcfg-rh plugin.
Logic is:
IPV6INIT=no   NM_SETTING_IP6_CONFIG_METHOD_IGNORE
else
IPV6_AUTOCONF=yes  -> NM_SETTING_IP6_CONFIG_METHOD_AUTO
DHCPV6C=yes  -> NM_SETTING_IP6_CONFIG_METHOD_DHCP
IPV6_AUTOCONF=no and no IPv6 address set -> 
NM_SETTING_IP6_CONFIG_METHOD_LINK_LOCAL
else NM_SETTING_IP6_CONFIG_METHOD_MANUAL

> So in essence the problem is the IPV6INIT flag is the wrong flag to be
> using for enabling and disabling IPv6 for a device.
> 
> The following seems to map what the "IPV6" Methods drop downs really do:
> 
> Ignore -> Configure with Router Advertisements
> Automatic -> Configure with Router Advertisements and then reconfigure with
> DHCPv6.  If DHCPv6 fails recycle the connection after a long timeout.
> 
> I haven't tried any of the other options.
> 
> Here is what is expected:
> 
> Ignore -> Configure with private address, or disable IPv6 for the device
> Automatic -> Configure with Router Advertisements or DHCPv6.  (Whichever
> succeeds first.)
> 

What is a done when configurong addresses is:
NM_SETTING_IP6_CONFIG_METHOD_AUTO or
NM_SETTING_IP6_CONFIG_METHOD_LINK_LOCAL
    SLAAC is started, which could in turn start DHCPv6 if it is required by RA

NM_SETTING_IP6_CONFIG_METHOD_DHCP
   DHCPv6 is started, RA is disabled

NM_SETTING_IP6_CONFIG_METHOD_IGNORE
  Accept RA is disabled or set as it was when NM started

NM_SETTING_IP6_CONFIG_METHOD_MANUAL
  Accept RA is disabled, manual addresses are set

details in src/nm-device.c:real_act_stage3_ip6_config_start()
> 
> Bill
> 

Jirka