Witness_node can not start under CentOS

I've successfuly built bitshare-2 under CentOS 7.2, however when starting the witness_node, it will quit with the following logs:
436191ms th_a       main.cpp:126                  main                 ] Writing new config file at /root/codebase/bitshares-2/build/programs/witness_node/witness_node_data_dir/config.ini
436191ms th_a       witness.cpp:89                plugin_initialize    ] witness plugin:  plugin_initialize() begin
436191ms th_a       witness.cpp:99                plugin_initialize    ] key_id_to_wif_pair: ["BTS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV","5KQwrPbwdL6PhXujxW37FSSQZ1JiwsST4cqQzDeyXtP79zkvFD3"]
436191ms th_a       witness.cpp:117               plugin_initialize    ] witness plugin:  plugin_initialize() end
436191ms th_a       application.cpp:403           startup              ] Replaying blockchain due to version upgrade
436191ms th_a       application.cpp:300           operator()           ] Initializing database...
443407ms th_a       db_management.cpp:51          reindex              ] reindexing blockchain
443407ms th_a       db_management.cpp:104         wipe                 ] Wiping database
443437ms th_a       object_database.cpp:87        wipe                 ] Wiping object database...
443437ms th_a       object_database.cpp:89        wipe                 ] Done wiping object databse.
443437ms th_a       object_database.cpp:94        open                 ] Opening object database from /root/codebase/bitshares-2/build/programs/witness_node/witness_node_data_dir/blockchain ...
443437ms th_a       object_database.cpp:100       open                 ] Done opening object database.
451914ms th_a       db_debug.cpp:85               debug_dump           ] total_balances[asset_id_type()].value: 12205723874026 core_asset_data.current_supply.value: 253409943611989
451934ms th_a       db_management.cpp:58          reindex              ] !no last block
451935ms th_a       db_management.cpp:59          reindex              ] last_block:
451986ms th_a       thread.cpp:95                 thread               ] name:ntp tid:140390530418432
451989ms th_a       thread.cpp:95                 thread               ] name:p2p tid:140390513633024
451990ms th_a       application.cpp:464           startup              ] 0 exception: unspecified
Unable to generate EC key
    {}
    p2p  elliptic_common.cpp:222 generate

    {}
    th_a  application.cpp:195 reset_p2p_node
451990ms th_a       application.cpp:1012          startup              ] 0 exception: unspecified
Unable to generate EC key
    {}
    p2p  elliptic_common.cpp:222 generate

    {}
    th_a  application.cpp:195 reset_p2p_node
rethrow
    {}
    th_a  application.cpp:464 startup
451990ms th_a       main.cpp:195                  main                 ] Exiting with error:
0 exception: unspecified
Unable to generate EC key
    {}
    p2p  elliptic_common.cpp:222 generate

    {}
    th_a  application.cpp:195 reset_p2p_node
rethrow
    {}
    th_a  application.cpp:464 startup
451991ms p2p        peer_database.cpp:133         close                ] error saving peer database to file
452257ms p2p        peer_database.cpp:133         close                ] error saving peer database to file
452258ms p2p        peer_database.cpp:133         close                ] error saving peer database to file
An exception of Unable to generate EC key is thrown and therefore the process quit directly
cryptonomex / graphene

Witness_node can not start under CentOS #659
