Packet loss simulation with ALTQ

[Nikos Vassiliadis]

On Tuesday 19 September 2006 18:24, Norberto Meijome wrote:
> hi there :)
> I was planning to migrate a 4.11 firewall using a combo of ipf/ipnat and
> ipfw pipe/dummynets to pf + ALTQ.

pf/ipf/ipfw & dummynet/ALTQ are available since 5.3-R if I recall correctly.

> One thing I haven't figured out how to do with pf is the plr option to the
> dummynet configuration - we use it to simulate modem connections or just
> simply bad links.

pf.conf manual(6.1-STABLE)

     probability <number>
           A probability attribute can be attached to a rule, with a value set
           between 0 and 1, bounds not included.  In that case, the rule will
           be honoured using the given probability value only.  For example,
           the following rule will drop 20% of incoming ICMP packets:

                 block in proto icmp probability 20%


> Also, is it definitely possibly to simulate the 'delay' option of dummynet
> with pf+ALTQ ?

No, ALTQ cannot delay packets, you have to use dummynet for this.

HTH, Nikos