整理日志中，突然发现有TNS-01101: Could not find service name for LISTENER_SCANx告警，检查了ps -ef | grep tns，发现SCAN是正常使用的，
如果没有设置TNS_ADMIN环境的话，lsnrctl服务是不可用的。

[grid@node1 ~]$ srvctl status scan 
SCAN VIP scan1 is enabled 
SCAN VIP scan1 is running on node node1 
SCAN VIP scan2 is enabled 
SCAN VIP scan2 is running on node node2 
SCAN VIP scan3 is enabled 
SCAN VIP scan3 is running on node node3

[grid@node1 ~]$ ps -ef| grep tns
grid 6230 1 0 Mar25 ? 00:00:18 /u01/app/11.2.0/grid/bin/tnslsnr LISTENER_SCAN1 -inherit

如果没有设置TNS_ADMIN环境的话：

[grid@node1 ~]$ lsnrctl service LISTENER_SCAN1 
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 16-FEB-2015 15:58:00
Copyright (c) 1991, 2009, Oracle. All rights reserved. 
TNS-01101: Could not find service name LISTENER_SCAN1


设置TNS_ADMIN环境：
$ export TNS_ADMIN=$GRID_HOME/network/admin
[grid@node1 ~]$ lsnrctl service LISTENER_SCAN1
LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 16-FEB-2015 17:26:03
Copyright (c) 1991, 2009, Oracle. All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_SCAN1)))
Services Summary...
Service "k1" has 1 instance(s).
  Instance "k11", status READY, has 1 handler(s) for this service...
  Handler(s):
  "DEDICATED" established:0 refused:0 state:ready
   REMOTE SERVER
    (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=node1-vip)(PORT=1521)))


导致这个错误的原因很简单，就是没有设置TNS_ADMIN环境，只要在Grid Infrastructure home设置好，当然还得检查下oracle_home的环境变量是否可用
env | grep ORACLE_HOME

同样的，最后也要检查下$GRID_HOME是否设置好。