pf ALTQ bandwidth limited to a 32bit value (4294Mb)

Bartek W. aka Mastier mistrzipan at
Thu Jul 7 09:05:21 UTC 2011

On 06.07.2011 18:50, Peter N. M. Hansteen wrote:
> Calomel Org<infallibilismindefeasibility at>  writes:
>> ALTQ using hfsc is limited to a maximum parent bandwidth of 4294Mb.
>> This value is 2^32 or 4,294,967,296 bits. If you set the bandwidth any
>> higher, altq will flip back to zero. This "bug" was found when trying
>> to test 10 gigabit and 40 gigabit bandwidth models. These tests were
>> done on OpenBSD 32bit and 64bit as well as FreeBSD 32bit and 64bit.
> Nice to hear you've got access to relatively high end gear for testing,
> I'm sure it will come in handy when the time comes to test any proposed
> fixes.
> The obvious workaround in the short term is to do the traffic shaping
> and filtering a bit closer to the end user, where bandwidth is a bit
> more scarce.  In the slightly longer term, I'm sure a verified bug
> report (with patches against -current code if feasible) would be much
> appreciated.
> - Peter
Haha ! I notice that too! Man, I'm shaping traffic for users end which 
total traffic is about 4Gb , but in my case I just used hfsc, and my 
"mighty" firewall generating script just divides the whole bandwidth  
like total/(no.users+1) for guaranteed speed. 1 stands for default queue.

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