报错现象：
alert日志出现少量的ORA-03137: malformed TTC packet from client rejected: [kpoal8Check-5]错误：
2023-04-28T13:33:22.430324+08:00
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl1/trace/orcl1_ora_3782406.trc (incident=2307783):
ORA-03137: malformed TTC packet from client rejected: [kpoal8Check-5] [0] [0x000000000] [0x000000000] [0] [0] [34856] []
Incident details in: /u01/app/oracle/diag/rdbms/orcl/orcl1/incident/incdir_2307783/orcl1_ora_3782406_i2307783.trc
2023-04-28T13:33:24.355666+08:00
Session (1824,63658): Bad TTC Packet Detected: Inbound connection from client
Session (1824,63658): Bad TTC Packet Detected: DB Logon User: YJ, Remote Machine: LJ-YJL\LJ-YJL-1F-N55, Program: oracle@hisdb1, OS User: user
Session (1824,63658): Bad TTC Packet Detected: Client IP Address: 172.26.49.55
The Call Stack Trace in the associated incident trace file shows:
opiierr <- kpoal8Check <- kpoal8 <- opiodr <- ttcpip <- opitsk <- opiino <- opiodr <- opidrv <- sou2o
Changes
The database was upgraded to 12.2 or higher. Cause
This issue is caused by the client version not being compatible with the RDBMS server version. Unlike previous versions, Oracle has added some strict checks starting 12.2.0.1 and client applications must comply with these checks.
This issue was investigated in unpublished Bug 26092744 which was closed as Not a Bug.