問題描述；
suse10sp2下安裝oracle11g客戶端，新建aipcti用戶，tnsping vsm（vsm爲客戶端下服務名）失敗，報錯：
TNS-03505: Failed to resolve name ，Used parameter files:
/opt/oracle/product/11g/db/network/admin/sqlnet.ora。
而在oracle用戶下直接執行此命令則沒有問題。
問題處理：
1，使用aipcti用戶直接tnsping +數據庫IP則沒有問題，但顯示是通過
Used EZCONNECT adapter to resolve the alias 來解析的。
2，打開客戶端下sqlnet.ora,裏面有通過客戶端訪問數據庫服務器順序。可以看到該文件中訪問順序是先訪問tnsnames,如果該文件下沒有相關內容或訪問失敗，再通過EZCONNECT訪問。
oracle@urp1vsmdb2:/opt/oracle/product/11g/db/network/admin> more sqlnet.ora
# sqlnet.ora Network Configuration File: /opt/oracle/product/11g/db/network/admin/sqlnet.ora
# Generated by Oracle configuration tools.
NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)
3，顯示tnsname.ora的權限：
oracle@urp1vsmdb2:/opt/oracle/product/11g/db/network/admin> ll -al tnsnames.ora
-rw-r----- 1 oracle oinstall 493 2011-09-23 16:09 tnsnames.ora
發現aipcti用戶對該文件沒有執行權限導致訪問失敗。
修改tnsnames.ora權限
oracle@urp1vsmdb2:/opt/oracle/product/11g/db/network/admin> chmod 644 tnsnames.ora
oracle@urp1vsmdb2:/opt/oracle/product/11g/db/network/admin> ls -al tnsnames.ora
-rw-r--r-- 1 oracle oinstall 493 2011-09-23 16:09 tnsnames.ora
4，修改後再次在aipcti下執行已經可以正常tnsping 客戶端
</home/aipcti/icddir/bin>tnsping vsm
TNS Ping Utility for Linux: Version 11.1.0.7.0 - Production on 26-9?? -2011 14:38:04
Copyright (c) 1997, 2008, Oracle. All rights reserved.
Used parameter files:
/opt/oracle/product/11g/db/network/admin/sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 10.110.153.64)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = uivr)))
OK (0 msec)
以下爲兩種方式下輸出結果對比：
1，aipcti用戶下使用tnsping+數據庫IP
</home/aipcti/icddir/bin>tnsping 10.110.153.64
TNS Ping Utility for Linux: Version 11.1.0.7.0 - Production on 26-9?? -2011 14:05:27
Copyright (c) 1997, 2008, Oracle. All rights reserved.
Used parameter files:
/opt/oracle/product/11g/db/network/admin/sqlnet.ora
Used EZCONNECT adapter to resolve the alias
Attempting to contact (DESCRIPTION=(CONNECT_DATA=(SERVICE_NAME=))(ADDRESS=(PROTOCOL=TCP)(HOST=10.110.153.64)(PORT=1521))(ADDRESS=(PROTOCOL=TCP)
(HOST=10.110.153.64)(PORT=1521))(ADDRESS=(PROTOCOL=TCP)(HOST=10.110.153.64)(PORT=1521)))
OK (0 msec)
2，aipcti用戶下使用tnsping+服務名，正常的：
oracle@urp1vsmdb2:/opt/oracle/product/11g/db/network/admin> tnsping vsm
TNS Ping Utility for Linux: Version 11.1.0.7.0 - Production on 26-SEP-2011 14:28:37
Copyright (c) 1997, 2008, Oracle. All rights reserved.
Used parameter files:
/opt/oracle/product/11g/db/network/admin/sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 10.110.153.64)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = uivr)))
OK (10 msec)