[FS#1159] SLAAC Only function on WAN interface if WAN is bridged

[LEDE Bugs]

The following task has a new comment added:

FS#1159 - SLAAC Only function on WAN interface if WAN is bridged
User who did this - Hans Dedecker (dedeckeh)

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The usage of br-wan2 as ifname in the interface wan2_6 is not really optimal as it requires knowledge about the "br-" prefixing for bridge interfaces.
A better config solution would be to decouple the bridge interface config from the interface protocol config as shown below


config interface 'wan2'
	option ipv6 '1'
	option ifname 'eth0.20'
	option type 'bridge'

config interface 'wan2_4'
	option proto 'dhcp'
	option ifname '@wan2'
	option hostname 'DLAlabLede'
	option metric '30'

config interface 'wan2_6'
	option proto 'dhcpv6'
	option ifname '@wan2'
	option reqaddress 'try'
	option reqprefix 'auto

Using the config above both the wan2_4 and wan2_6 interface use automatically br-wan but the wan2_6 interface is not dependent on the wan2_4 interface having an IPv4 address
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=1159#comment3861