logmask (integer):

    Default value: 0. A mask whose bits when set allow certain categories of
    log messages to be generated. The value of this setting will be applied
    every time the utserver process starts.

    The bits (0 - 31) in the value of this setting correspond to a set of
    internal events and subsystems. The usage of these bits may change without
    advance notice in a future release.

      □ 3 - send have
      □ 6 - hole punch
      □ 7 - got bad piece request
      □ 8 - trace
      □ 9 - piece picker
      □ 10 - got bad cancel
      □ 11 - got bad unchoke
      □ 12 - got bad piece
      □ 13 - rss
      □ 14 - rss error
      □ 15 - got have
      □ 16 - got bad have
      □ 17 - error
      □ 18 - aggregated
      □ 19 - disconnect
      □ 20 - out connect
      □ 21 - in connect
      □ 22 - UPnP
      □ 23 - UPnP error
      □ 24 - NATPMP
      □ 25 - NATPMP error
      □ 26 - metadata finish
      □ 27 - web UI
      □ 28 - got bad reject
      □ 29 - pex
      □ 30 - peer messages
      □ 31 - blocked connect