After the PPPoE link of vyos was accidentally established, the dhcp6c service could not be restarted automatically. I checked the code of the following address:
https://github.com/vyos/vyos-1x/blob/current/data/templates/pppoe/ipv6-up.script.tmpl
https://github.com/vyos/vyos-1x/blob/current/data/templates/pppoe/ip-down.script.tmpl
```
{% if dhcpv6_pd_interfaces %}
# Start wide dhcpv6 client
systemctl stop dhcp6c@{{ ifname }}.service
{% endif %}
```
When to change to the following code will be better?
```
{% if dhcpv6_options is defined and dhcpv6_options.prefix_delegation is defined %}
# Stop wide dhcpv6 client
systemctl stop dhcp6c@{{ ifname }}.service
{% endif %}
```
This may be prompted after an accidental Reconnection:
```
Jul 08 12:16:02 vyos dhcp6c[2969]: copy_option: set elapsed time (len 2)
Jul 08 12:16:02 vyos dhcp6c[2969]: copy_option: set option request (len 4)
Jul 08 12:16:02 vyos dhcp6c[2969]: client6_send: transmit failed: Network is unreachable
Jul 08 12:16:02 vyos dhcp6c[2969]: dhcp6_reset_timer: reset a timer on pppoe0, state=SOLICIT, timeo=751, retrans=129708
Jul 08 12:16:36 vyos dhcp6c[2969]: copy_option: set client ID (len 14)
Jul 08 12:16:36 vyos dhcp6c[2969]: copyout_option: set identity association
Jul 08 12:16:36 vyos dhcp6c[2969]: copy_option: set elapsed time (len 2)
Jul 08 12:16:36 vyos dhcp6c[2969]: copy_option: set option request (len 4)
Jul 08 12:16:36 vyos dhcp6c[2969]: client6_send: transmit failed: Network is unreachable
Jul 08 12:16:36 vyos dhcp6c[2969]: dhcp6_reset_timer: reset a timer on pppoe0, state=SOLICIT, timeo=1471, retrans=126768
```