anchor.diff:      ok.
   
   init_per_testcase(_, Config) ->
  +%%     tracer:start(node()),
  +%%     tracer:trace_calls(test_node_starter, prepare_test_environment),
  +%%     tracer:trace_calls(test_node_starter, get_cookies),
  +%%     tracer:trace_calls(test_node_starter, set_cookies),
  +%%     tracer:trace_calls(test_node_starter, ping_nodes),
       NewConfig = ?TEST_INIT(Config, ?TEST_FILE(Config, "env_desc.json")),
  +%%     tracer:stop(),
       application:start(ssl2),
       hackney:start(),
       [Worker1, Worker2 | _] = ?config(op_worker_nodes, NewConfig),
  
positive.code: get_node_ip(Node) ->
      CMD = "docker inspect --format '{{ .NetworkSettings.IPAddress }}'" ++ " " ++
          utils:get_host(Node),
      re:replace(os:cmd(CMD), "\\s+", "", [global, {return, list}]).
negative.code:     end_per_testcase/2]).
  
  -export([less_than_block_fetch_test/1, exact_block_size_fetch_test/1,
      more_than_block_fetch_test/1, more_than_block_fetch_test2/1, cancel_fetch_test/1,
      error_open_fun_test/1, error_read_fun_test/1, error_write_fun_test/1, many_requests_test/1,
      many_requests_to_one_file/1, bad_formatted_request_test/1, bad_file_offset_test/1]).
  
  -export([read_fun/1, write_fun/1, counter/1, onCompleteCounter/1]).
  