another Xserver is already active on display 10

[20170517-15:42:36] [WARN ] [init:45] libscp initialized

[20170517-15:42:36] [CORE ] starting sesman with pid 2529

[20170517-15:42:36] [INFO ] listening...

[20170517-15:50:34] [INFO ] scp thread on sck 7 started successfully

[20170517-15:50:34] [INFO ] ++ created session (access granted): username root, ip 192.168.0.55:14078 - socket: 7

[20170517-15:50:34] [INFO ] starting Xvnc session...

[20170517-15:50:34] [CORE ] error starting X server - user root - pid 2557

[20170517-15:50:35] [DEBUG] errno: 2, description: No such file or directory

[20170517-15:50:35] [DEBUG] execve parameter list: 16

[20170517-15:50:35] [DEBUG]         argv[0] = Xvnc

[20170517-15:50:35] [DEBUG]         argv[1] = :10

[20170517-15:50:35] [DEBUG]         argv[2] = -geometry

[20170517-15:50:35] [DEBUG]         argv[3] = 1280x1024

[20170517-15:50:35] [DEBUG]         argv[4] = -depth

[20170517-15:50:35] [DEBUG]         argv[5] = 24

[20170517-15:50:35] [DEBUG]         argv[6] = -rfbauth

[20170517-15:50:35] [DEBUG]         argv[7] = /root/.vnc/sesman_root_passwd

[20170517-15:50:35] [DEBUG]         argv[8] = -bs

[20170517-15:50:35] [DEBUG]         argv[9] = -ac

[20170517-15:50:35] [DEBUG]         argv[10] = -nolisten

[20170517-15:50:35] [DEBUG]         argv[11] = tcp

[20170517-15:50:35] [DEBUG]         argv[12] = -localhost

[20170517-15:50:35] [DEBUG]         argv[13] = -dpi

[20170517-15:50:35] [DEBUG]         argv[14] = 96

[20170517-15:50:35] [DEBUG]         argv[15] = (null)

[20170517-15:50:44] [ERROR] X server for display 10 startup timeout

[20170517-15:50:44] [INFO ] starting xrdp-sessvc - xpid=2557 - wmpid=2556

[20170517-15:50:44] [ERROR] X server for display 10 startup timeout

[20170517-15:50:45] [ERROR] another Xserver is already active on display 10

[20170517-15:50:45] [DEBUG] aborting connection...

[20170517-15:50:45] [INFO ] ++ terminated session:  username root, display :10.0, session_pid 2555, ip 192.168.0.55:14078 - socket: 7

위와 같이 에러가 발생한다면(centos6.5기준)

# yum install pixman libXfont tigervnc-server vnc*

추가로 설치하면 정상적으로 접속이 된다.