[FS#1393] netifd: "ubus call network reload" can't remove the deprecated ipv6 prefix delegation on lan

[LEDE Bugs]

The following task has a new comment added:

FS#1393 - netifd: "ubus call network reload" can't remove the deprecated ipv6 prefix delegation on lan
User who did this - Kai Song (alfred.song)

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Hi Hans, 

I re-checked the lifetime, routing, and odhcpd behavior following your comments.
when DHCPv6 wan connection is removed.
* The preferred lifetime is set to 0, and this delegated address changed to "deprecated" state

ip -6 addr show
......
10: br-lan:  mtu 1500 
    inet6 2001:db8:3200::1/64 scope global noprefixroute 
       valid_lft forever preferred_lft forever
    inet6 2001:db8:ffff:f000::1/64 scope global deprecated noprefixroute dynamic 
       valid_lft 42sec preferred_lft 0sec
    inet6 fe80::5054:ff:fe12:3456/64 scope link 
       valid_lft forever preferred_lft forever
......

* The routing of this pd was removed
* odhcpd continue to advertise the old prefix, until its valid lifetime expired. But the advertised preferred_lft and valid_lft are 0

I believe this is acceptable.

Thanks for the reply.
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=1393#comment4407