freebsd stable - Jul 2018 - Removing IPv6 address causes all IPv6 traffic to stop working

On a older server running FreeBSD 10.2 i have a number of jails. For
migration to FreeBSD I'm planning to shutdown the jail, move the data to
the new server and spin up the jail there. IP addresses are alse moved.

When I remove an IPv6 address with the following command 'ifconfig em0
inet6 v6address/48 delete', all IPv6 traffic on the server stops
working. I can reach IPv6 from outside to the server and from the server
to outside, but everything on the server (jail to jail for example)
immediatly stops working. IPv4 works normally
Unfortunately it's not feasible to bing-bang migrate everything,
ignoring ipv6 is not possible because a lot of the jails interact with
each other with ipv6 (some even exclusivly)

What can cause this?


Regards,

Frank de Bot

How did you assign the jails' IPv6 addresses in the first place?  The usual
way is to assign them as /128 aliases, in which case the command to remove
them would include a "/128", not "/48".  I think when
you're deleting a
"/48" you're also removing some routes that the jail host is
using.
-Alan

On Thu, Jul 12, 2018 at 4:30 PM, Frank de Bot (lists) <lists at
searchy.net>
wrote:
> On a older server running FreeBSD 10.2 i have a number of jails. For
> migration to FreeBSD I'm planning to shutdown the jail, move the data
to
> the new server and spin up the jail there. IP addresses are alse moved.
>
> When I remove an IPv6 address with the following command 'ifconfig em0
> inet6 v6address/48 delete', all IPv6 traffic on the server stops
> working. I can reach IPv6 from outside to the server and from the server
> to outside, but everything on the server (jail to jail for example)
> immediatly stops working. IPv4 works normally
> Unfortunately it's not feasible to bing-bang migrate everything,
> ignoring ipv6 is not possible because a lot of the jails interact with
> each other with ipv6 (some even exclusivly)
>
> What can cause this?
>
>
> Regards,
>
> Frank de Bot
> _______________________________________________
> freebsd-stable at freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-stable
> To unsubscribe, send any mail to "freebsd-stable-unsubscribe at
freebsd.org"
>