# Allow router advertisements on a nic without getting SLAAC address



## athan (Nov 26, 2018)

Is it possible to enable getting router advertisements on a network interface but disable SLAAC autoconf-ed address?

RA is necessary for stateful DHCPv6 and prefix delegation but "accept_rtadv" also gives a SLAAC address which I really don't need.

Any idea?


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## VladiBG (Nov 26, 2018)

ifconfig(8)
*-accept*_*rtadv*
         Clear a flag *accept*_*rtadv*.

/etc/rc.conf example:
ifconfig_re0_ipv6="inet6 -accept_rtadv"


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## athan (Nov 26, 2018)

The "-accept_rtadv" flag cannot be used as it disables router advertisements that are necessary for stateful DHCPv6 to work.


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## VladiBG (Nov 26, 2018)

In the man page the next section describe how to disable the auto configuration just below *-accept*_*rtadv*

Also you may check this post:
https://forums.freebsd.org/threads/ipv6-gateway.53522/post-301886


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## athan (Nov 26, 2018)

Do you mean the *-autoconf* flag?
I'm afraid it doesn't work that way. It still gets a slaac address...

According to this post 11.2 revision "autoconf" is an address
property, not something you can set for an interface.

What I'm really looking for is something like linux *net.ipv6.conf.<IF>.autoconf* sysctl setting that leaves RA enabled but disables auto-configuring eui64 addresses.


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