Hi,
Sometimes You can get “ORA-12636: Packet send failed ” error.
Details of error are as follows.
ORA-12636: Packet send failed
Cause: A process was unable to send a packet to another process. Possible causes are:1. The other process was terminated.
2. The machine on which the other process is running went down.
3. Some other communications error occurred.
Action: If the cause is not obvious, contact Oracle Customer Support.
As an immediate workaround, disable Kerberos Authentication in the sqlnet.ora file.
The following lines may or may not be included, so comment all relevant lines to be sure:
# SQLNET.AUTHENTICATION_SERVICES = (BEQ,KERBEROS5PRE) # SQLNET.KERBEROS5_CC_NAME = /var/opt/oracle/krb/cc/krb5cc_11 # SQLNET.KERBEROS5_CONF = /var/opt/oracle/krb5.conf # SQLNET.FALLBACK_AUTHENTICATION = TRUE # SQLNET.AUTHENTICATION_KERBEROS5_SERVICE = oracle # SQLNET.KERBEROS5_KEYTAB = /var/opt/oracle/ora1111.keytab # SQLNET.KERBEROS5_CONF_MIT = TRUE
Now when connecting, it should work or progress to the next logical error:
$ sqlplus rcrow/<pwd>@MSDB SQL*Plus: Release 12.1.0.2.0 Production on Fri Jun 29 14:13:47 2018 Copyright (c) 1982, 2014, Oracle. All rights reserved. Last Successful login time: Fri Jun 29 2018 14:11:44 -04:00 Connected to: Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production SQL>
Do you want to learn more details about RMAN, then read the following articles.
https://ittutorial.org/rman-backup-restore-and-recovery-tutorials-for-beginners-in-the-oracle-database/