RA learned prefix added to routing table is not deleted on ra route flush

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Hi All,
      When I enabled Router Advertisement on the interface on which I want
to receive RA, the received prefix was added to the routing table. The
default route was added with the tag "ra" but not the prefix.

$ip -6 route
::1 dev lo proto kernel metric 256 pref medium
*fdxx:xxxx:xxxx:xxxx::/64* dev ens192 proto kernel metric 256 expires
2591996sec pref medium
fe80::/64 dev ens192 proto kernel metric 256 pref medium
default via fe80::xxx:xxxx:xxxx:xxxx dev ens192 proto *ra* metric 1024
expires 1796sec hoplimit 64 pref medium

When I flush the ra learned routes using the following command, only the
default route gets removed. Why doesn't the prefix which is *bolded* above
get deleted too? It is marked as added by the *kernel*, but the kernel
added it because it came from an RA.

*sudo ip -6 route flush protocol ra*.

::1 dev lo proto kernel metric 256 pref medium
*fdxx:xxxx:xxxx:xxxx::/64* dev ens192 proto kernel metric 256 expires
2591996sec pref medium
fe80::/64 dev ens192 proto kernel metric 256 pref medium

Dheeraj

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<div dir=3D"ltr"><div>Hi All,</div><div>=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 When=
 I enabled Router Advertisement on the interface on which I want to receive=
 RA, the received prefix was added to the routing table. The default route =
was added with the tag &quot;ra&quot; but not the prefix.<br></div><div><br=
></div><div><div>$ip -6 route<br>::1 dev lo proto kernel metric 256 pref me=
dium<br><b>fdxx:xxxx:xxxx:xxxx::/64</b> dev ens192 proto kernel metric 256 =
expires 2591996sec pref medium<br>fe80::/64 dev ens192 proto kernel metric =
256 pref medium<br>default via fe80::xxx:xxxx:xxxx:xxxx dev ens192 proto <b=
>ra</b> metric 1024 expires 1796sec hoplimit 64 pref medium</div><div><br><=
/div></div><div>When I flush the ra learned routes using the following comm=
and, only the default route gets removed. Why doesn&#39;t the prefix which =
is <b>bolded</b> above get deleted too? It is marked as added by the <b>ker=
nel</b>, but the kernel added it because it came from an RA.<br></div><div>=
<br></div><div> <strong>sudo ip -6 route flush protocol ra</strong>.</div><=
div><br></div><div>::1 dev lo proto kernel metric 256 pref medium<br><b>fdx=
x:xxxx:xxxx:xxxx::/64</b> dev ens192 proto kernel metric 256 expires 259199=
6sec pref medium<br>fe80::/64 dev ens192 proto kernel metric 256 pref mediu=
m</div><div><br></div><div></div><div>Dheeraj<br></div></div>

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