一.問題描述
用expdp對oracle資料庫的一個schema匯出操作時，報ORA-12170錯誤，如下：
expdp ab/"[email protected]" directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log

Export: Release 11.2.0.4.0 - Production on Mon Oct 10 16:42:25 2016

Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.

UDE-12170: operation generated ORACLE error 12170
ORA-12170: TNS:Connect timeout occurred

二.問題分析

1.檢視資料庫的tnsnames.ora和listener.ora兩檔案設定正常.
2.檢查使用者密碼是否正確，確認帳號和密碼能連上資料庫.
3.檢查資料庫主機的連線數，是否太多.
共232個連線：
-bash-4.1$ netstat -an|grep 1529|grep "ESTABLISHED"|grep -v grep|wc -l
232
而開啟檔案控制代碼和最大使用者程序數都非常大。
-bash-4.1$ ulimit -a
core file size (blocks, -c) unlimited
data seg size (kbytes, -d) unlimited
file size (blocks, -f) unlimited
open files (-n) 65536
pipe size (512 bytes, -p) 10
stack size (kbytes, -s) 781250
cpu time (seconds, -t) unlimited
max user processes (-u) 65541
virtual memory (kbytes, -v) 536870912

4.檢查資料庫的alert log沒有任何報錯.
5.嘗試用dba許可權可正常匯出

expdp zengxuewen directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log

-bash-4.1$ expdp zengxuewen directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log

Export: Release 11.2.0.4.0 - Production on Mon Oct 10 17:01:09 2016

Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
Password:

Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
FLASHBACK automatically enabled to preserve database integrity.
Starting "ZENGXUEWEN"."SYS_EXPORT_SCHEMA_01": zengxuewen/******** directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log
Estimate in progress using BLOCKS method...
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 5.518 GB
Processing object type SCHEMA_EXPORT/USER
Processing object type SCHEMA_EXPORT/SYSTEM_GRANT
Processing object type SCHEMA_EXPORT/ROLE_GRANT

6.同樣用以下方式，根據提示輸入密碼也能正常匯出

-bash-4.1$expdp ab directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log

Export: Release 11.2.0.4.0 - Production on Mon Oct 10 17:01:09 2016

Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
Password:

Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
FLASHBACK automatically enabled to preserve database integrity.
Starting "ZENGXUEWEN"."SYS_EXPORT_SCHEMA_01": ab/******** directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log
Estimate in progress using BLOCKS method...
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 5.518 GB
Processing object type SCHEMA_EXPORT/USER
Processing object type SCHEMA_EXPORT/SYSTEM_GRANT
Processing object type SCHEMA_EXPORT/ROLE_GRANT

從上面排查步驟來看，問題還是出在密碼識別和驗證上面，因為密碼中有特殊字元@。

三.問題處理

 對密碼中特殊字元@進行處理，在密碼上加""，使用者和密碼加'',如下：
-bash-4.1$ expdp 'ab/"[email protected]"' directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log碼上加""，使用者和密碼加'
-bash-4.1$expdp 'ab/"[email protected]"' directory=dump schemas=ab dumpfile=ab-1010b.dmp logfile=ab1010.log

Export: Release 11.2.0.4.0 - Production on Mon Oct 10 17:20:27 2016

Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.

Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
FLASHBACK automatically enabled to preserve database integrity.
Starting "RDM"."SYS_EXPORT_SCHEMA_01": ab/******** directory=dump schemas=ab dumpfile=ab1010b.dmp logfile=ab1010.log
Estimate in progress using BLOCKS method...
Processing object type SCHEMA_EXPORT/TABLE/TABLE_DATA
Total estimation using BLOCKS method: 5.518 GB
Processing object type SCHEMA_EXPORT/PRE_SCHEMA/PROCACT_SCHEMA
Processing object type SCHEMA_EXPORT/SEQUENCE/SEQUENCE

................................

這樣就能正常匯出。