FreeBSD 7.0 manual page repository

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ALTQ - alternate queuing of network packets



      ALTQ - alternate queuing of network packets


      options ALTQ
      options ALTQ_CBQ
      options ALTQ_RED
      options ALTQ_RIO
      options ALTQ_HFSC
      options ALTQ_CDNR
      options ALTQ_PRIQ


      The ALTQ framework provides several disciplines for queuing outgoing net‐
      work packets.  This is done by modifications to the interface packet
      queues.  See altq(9) for details.
      The user interface for ALTQ is implemented by the pfctl(8) utility, so
      please refer to the pfctl(8) and the pf.conf(5) manpages for a complete
      description of the ALTQ capabilities and how to use it.
    Kernel Options
      The following options in the kernel configuration file are related to
      ALTQ operation:
      ALTQ        Enable ALTQ.
      ALTQ_CBQ    Build the “Class Based Queuing” discipline.
      ALTQ_RED    Build the “Random Early Detection” extension.
      ALTQ_RIO    Build “Random Early Drop” for input and output.
      ALTQ_HFSC   Build the “Hierarchical Packet Scheduler” discipline.
      ALTQ_CDNR   Build the traffic conditioner.  This option is meaningless at
                  the moment as the conditioner is not used by any of the
                  available disciplines or consumers.
      ALTQ_PRIQ   Build the “Priority Queuing” discipline.
      ALTQ_NOPCC  Required if the TSC is unusable.
      ALTQ_DEBUG  Enable additional debugging facilities.
      Note that ALTQ-disciplines cannot be loaded as kernel modules.  In order
      to use a certain discipline you have to build it into a custom kernel.
      The pf(4) interface, that is required for the configuration process of
      ALTQ can be loaded as a module.
      The driver modifications described in altq(9) are required to use a cer‐
      tain network card with ALTQ.  They have been applied to the following
      hardware drivers: an(4), ath(4), aue(4), awi(4), bce(4), bfe(4), bge(4),
      dc(4), de(4), ed(4), em(4), ep(4), fxp(4), gem(4), hme(4), ipw(4),
      iwi(4), le(4), msk(4), mxge(4), my(4), nfe(4), npe(4), nve(4), ral(4),
      re(4), rl(4), rum(4), sf(4), sis(4), sk(4), ste(4), stge(4), udav(4),
      ural(4), vge(4), vr(4), wi(4), and xl(4).
      The ndis(4) framework also has support for ALTQ and thus all encapsulated
      The tun(4) and ng_iface(4) pseudo drivers also do support ALTQ.
      pf(4), pf.conf(5), ipfw(8), pfctl(8), altq(9)


Based on BSD UNIX
FreeBSD is an advanced operating system for x86 compatible (including Pentium and Athlon), amd64 compatible (including Opteron, Athlon64, and EM64T), UltraSPARC, IA-64, PC-98 and ARM architectures. It is derived from BSD, the version of UNIX developed at the University of California, Berkeley. It is developed and maintained by a large team of individuals. Additional platforms are in various stages of development.