bgpd/bgp_damp.h

   1 /* BGP flap dampening
   2    Copyright (C) 2001 IP Infusion Inc.
   3
   4 This file is part of GNU Zebra.
   5
   6 GNU Zebra is free software; you can redistribute it and/or modify it
   7 under the terms of the GNU General Public License as published by the
   8 Free Software Foundation; either version 2, or (at your option) any
   9 later version.
  10
  11 GNU Zebra is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Zebra; see the file COPYING.  If not, write to the Free
  18 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  20
  21 /* Structure maintained on a per-route basis. */
  22 struct bgp_damp_info
  23 {
  24   /* Doubly linked list.  This information must be linked to
  25      reuse_list or no_reuse_list.  */
  26   struct bgp_damp_info *next;
  27   struct bgp_damp_info *prev;
  28
  29   /* Figure-of-merit.  */
  30   int penalty;
  31
  32   /* Number of flapping.  */
  33   int flap;
  34
  35   /* First flap time  */
  36   time_t start_time;
  37
  38   /* Last time penalty was updated.  */
  39   time_t t_updated;
  40
  41   /* Time of route start to be suppressed.  */
  42   time_t suppress_time;
  43
  44   /* Back reference to bgp_info. */
  45   struct bgp_info *binfo;
  46
  47   /* Back reference to bgp_node. */
  48   struct bgp_node *rn;
  49
  50   /* Current index in the reuse_list. */
  51   int index;
  52
  53   /* Last time message type. */
  54   u_char lastrecord;
  55 #define BGP_RECORD_UPDATE       1
  56 #define BGP_RECORD_WITHDRAW     2
  57
  58   afi_t afi;
  59   safi_t safi;
  60 };
  61
  62 /* Specified parameter set configuration. */
  63 struct bgp_damp_config
  64 {
  65   /* Value over which routes suppressed.  */
  66   int suppress_value;
  67
  68   /* Value below which suppressed routes reused.  */
  69   int reuse_limit;
  70
  71   /* Max time a route can be suppressed.  */
  72   int max_suppress_time;
  73
  74   /* Time during which accumulated penalty reduces by half.  */
  75   int half_life;
  76
  77   /* Non-configurable parameters but fixed at implementation time.
  78    * To change this values, init_bgp_damp() should be modified.
  79    */
  80   int tmax;               /* Max time previous instability retained */
  81   int reuse_list_size;          /* Number of reuse lists */
  82   int reuse_index_size;         /* Size of reuse index array */
  83
  84   /* Non-configurable parameters.  Most of these are calculated from
  85    * the configurable parameters above.
  86    */
  87   unsigned int ceiling;         /* Max value a penalty can attain */
  88   int decay_rate_per_tick;      /* Calculated from half-life */
  89   int decay_array_size;         /* Calculated using config parameters */
  90   double scale_factor;
  91   int reuse_scale_factor;
  92
  93   /* Decay array per-set based. */
  94   double *decay_array;
  95
  96   /* Reuse index array per-set based. */
  97   int *reuse_index;
  98
  99   /* Reuse list array per-set based. */
 100   struct bgp_damp_info **reuse_list;
 101   int reuse_offset;
 102
 103   /* All dampening information which is not on reuse list.  */
 104   struct bgp_damp_info *no_reuse_list;
 105
 106   /* Reuse timer thread per-set base. */
 107   struct thread* t_reuse;
 108 };
 109
 110 #define BGP_DAMP_NONE           0
 111 #define BGP_DAMP_USED           1
 112 #define BGP_DAMP_SUPPRESSED     2
 113
 114 /* Time granularity for reuse lists */
 115 #define DELTA_REUSE               10
 116
 117 /* Time granularity for decay arrays */
 118 #define DELTA_T                    5
 119
 120 #define DEFAULT_PENALTY         1000
 121
 122 #define DEFAULT_HALF_LIFE         15
 123 #define DEFAULT_REUSE            750
 124 #define DEFAULT_SUPPRESS        2000
 125
 126 #define REUSE_LIST_SIZE          256
 127 #define REUSE_ARRAY_SIZE        1024
 128
 129 int bgp_damp_enable (struct bgp *, afi_t, safi_t, int, int, int, int);
 130 int bgp_damp_disable (struct bgp *, afi_t, safi_t);
 131 int bgp_damp_withdraw (struct bgp_info *, struct bgp_node *,
 132                        afi_t, safi_t, int);
 133 int bgp_damp_update (struct bgp_info *, struct bgp_node *, afi_t, safi_t);
 134 int bgp_damp_scan (struct bgp_info *, afi_t, safi_t);
 135 void bgp_damp_info_free (struct bgp_damp_info *, int);
 136 void bgp_damp_info_clean ();
 137 char * bgp_get_reuse_time (int, char*, size_t);
 138 int bgp_damp_decay (time_t, int);
 139 int bgp_config_write_damp (struct vty *);
 140 void bgp_damp_info_vty (struct vty *, struct bgp_info *);
 141 char * bgp_damp_reuse_time_vty (struct vty *, struct bgp_info *);