公司搬家，新换的网络，两个数据库直接突然无法连接了，同网段环境可以，具体如下： 通过sqlplus或tnsping客户端 测试，报以下错误 ``` [oracle@mytest01 ~]$ tnsping ssdb215 TNS Ping Utility for Linux: Version 11.2.0.4.0 - Production on 11-FEB-2023 19:18:46 Copyright (c) 1997, 2013, Oracle. All rights reserved. Used parameter files: Used TNSNAMES adapter to resolve the alias Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.215)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = orcl))) TNS-12547: TNS:lost contact [oracle@mytest01 ~]$ sqlplus ord/test123@ssdb215 SQL*Plus: Release 11.2.0.4.0 Production on Sat Feb 11 19:19:09 2023 Copyright (c) 1982, 2013, Oracle. All rights reserved. ERROR: ORA-12547: TNS:lost contact ``` 通过检查，数据库、监听均正常，ping网络也正常。其他同网段也能连接，开始通过tnsping跟踪来分析，跟踪命令如下： ``` #sqlnet.ora 文件写入以下命令 tnsping.trace_level=support tnsping.trace_directory=/u01/app/oracle/product/11.2.0/db_home/network/admin ``` 除了可以跟踪tnsping命令，还可以跟踪客户端连接，本案例跟踪tnsping。 通过跟踪文件分析，网络发包正常，回包报错 ``` ## 发包成功 nscon: sending NSPTCN packet nspsend: entry nspsend: plen=87, type=1 nttwr: entry nttwr: socket 5 had bytes written=87 nttwr: exit nspsend: packet dump nspsend: 00 57 00 00 01 00 00 00 |.W......| nspsend: 01 3A 01 2C 00 00 20 00 |.:.,....| nspsend: FF FF 7F 08 00 00 01 00 |........| nspsend: 00 1D 00 3A 00 00 00 00 |...:....| nspsend: 00 00 00 00 00 00 00 00 |........| nspsend: 00 00 00 00 00 00 00 00 |........| nspsend: 00 00 00 00 00 00 00 00 |........| nspsend: 00 00 28 43 4F 4E 4E 45 |..(CONNE| nspsend: 43 54 5F 44 41 54 41 3D |CT_DATA=| nspsend: 28 43 4F 4D 4D 41 4E 44 |(COMMAND| nspsend: 3D 70 69 6E 67 29 29 |=ping)) | nspsend: 87 bytes to transport nspsend: normal exit ##回包出现错误 nscon: recving a packet nsprecv: entry nsprecv: reading from transport... nttrd: entry ntt2err: entry ntt2err: soc 5 error - operation=5, ntresnt[0]=517, ntresnt[1]=104, ntresnt[2]=0 ntt2err: exit nttrd: exit nsprecv: reading from transport... nttrd: entry ntt2err: entry ntt2err: soc 5 error - operation=5, ntresnt[0]=517, ntresnt[1]=104, ntresnt[2]=0 ntt2err: exit nttrd: exit nsprecv: error exit nserror: entry nserror: nsres: id=0, op=68, ns=12547, ns2=12560; nt[0]=517, nt[1]=104, nt[2]=0; ora[0]=0, ora[1]=0, ora[2]=0 nscon: error exit ``` 公司内部，可以有两种方式处理，一个是协调网络工程师，处理网络问题。再个就是调整数据库网络，改为其他网段，因为两个数据库中间是数据同步，不涉及业务，故调整了数据库网络。