Table of Contents

Setting

Setting up subnets for balancing

Balancing applies only to IP addresses belonging to the AS defined as local in asnum.dscp.

  1. Define an autonomous system with IP addresses that are used by subscribers:
    vi aslocal.txt
    10.0.0.0/8 64511
    172.16.0.0/12 64511
    192.168.0.0/16 64511
    cat aslocal.txt | as2bin /etc/dpi/aslocal.bin
  2. Mark a given autonomous system as local:
    vi my_as_dscp.txt
    64511 local
    10415 local
    cat my_as_dscp.txt | as2dscp /etc/dpi/asnum.dscp

    You can use either a custom AS or a public AS as the AS.
    Read more at the link

  3. A reload must be performed to apply the parameters:
    service fastdpi reload

Setting /etc/dpi/fastdpi.conf

  1. Define the input and output interfaces in the configuration file.
    The input interfaces to which the traffic mirror is fed are specified in the in_dev parameter, and the output interfaces are specified in out_dev.
    Interfaces do not form pairs and species constructs are allowed:
    in_dev=05-00.0:05-00.1:05-00.2:05-00.3:0b-00.0:0b-00.1:0b-00.2:0b-00.3
    out_dev=08-00.0:08-00.1:08-00.2:08-00.3

    Or

    in_dev=05-00.0
    out_dev=out_dev=08-00.0:08-00.1:08-00.2:08-00.3
  2. Enable balancing mode in the enable_l2_lb parameter, where:
    • 0 — deactivate balancing;
    • 1 — activate balancing.
  3. Determine by what value to initialize the hash table in the lb_hash_out_dev_type parameter, where:
    • 0 — use the internal index of the output interface;
    • 1 — use the interface name from [in|out]_dev.
  4. Select an engine to handle thread dispatchers in the dpdk_engine parameter, where:
    • 0 — read/write default engine, one dispatcher for everything;
    • 1 — read/write engine with two dispatcher threads: a dispatcher for each direction;
    • 2 — Read/write engine with RSS support: for each direction, dpdk_rss dispatchers are created (default dpdk_rss=2), so total number of dispatchers = 2 * dpdk_rss— to work with in_dev, and a separate dispatcher to work with out_dev.
      When the parameter value is 2, the mqrx_lb_engine engine is activated. The principle of operation is the same as in the usual mode dpdk_engine=2, only rss is enabled on in_dev, and only one rx queue is created on out_dev.

      Learn more about the dpdk_engine parameter by clicking here.
  5. Select a balancing algorithm. The maglev algorithm with fixed hash table size is used for traffic balancing, where:
    • 1 — if src and dst ip are both local, then hash is calculated based on these two addresses;
    • 2 — if only src ip local, then hash is calculated based on src ip;
    • 3 — if only dst ip local, hash is calculated on the basis of dst ip;
    • 4 — hash is calculated based on src and dst ip.

      Based on the calculated hash value, the output interface is determined by determining the index of the hash table cell containing the interface index from the array of output interfaces.