Restaarting PF and its effects on jails and vms

Arthur Chance freebsd at
Fri Mar 24 09:22:05 UTC 2017

On 24/03/2017 09:16, Odhiambo Washington wrote:
> On 24 March 2017 at 11:20, Arthur Chance <freebsd at> wrote:
>> On 23/03/2017 18:29, James B. Byrne via freebsd-questions wrote:
>>> I am revising the pf configuration for the FreeBSD-10.3 host of a
>>> number of FreeBSD-11.0 BHyve instances. When I restart PF on the host
>>> then traffic to a number of guests gets blocked even though the
>>> ruleset says it should not be.
>>> Since the incoming ports for the blocked traffic appear to be from the
>>> upper dynamic range I infer that this traffic is related to
>>> connections established before PF was restarted and are now 'orphaned'
>>> in consequence.  In other words, had the initial connection between
>>> client anf service been made while PF was already running the traffic
>>> being blocked following a restart would have been let through as being
>>> part of an established connection.
>>> What is the recommended way of dealing with this issue when restarting
>>> PF, if there is one?
>> Don't restart pf, reload it. "service pf reload" goes to great lengths
>> not to interfere with existing connections whereas "service pf restart"
>> blows away everything before restarting.
>> This is fresh in my mind because I made exactly the same mistake last
>> week before remembering to reload. :-)
> A quick one, before I get to RTFM, is there an equivalent 'reload' option
> for pfctl (9.3-STABLE)?

It's all pfctl. By using service(8) I was referring to the rc.d script
for pf, but that sits over pfctl. The reload part is (on 10.3)

        echo "Reloading pf rules."
        $pf_program -n -f "$pf_rules" || return 1
        # Flush everything but existing state entries that way when
        # rules are read in, it doesn't break established connections.
        $pf_program -Fnat -Fqueue -Frules -FSources -Finfo -FTables
-Fosfp > /dev/null 2>&1
        $pf_program -f "$pf_rules" $pf_flags

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