Background:
I believe most of Informix users are familiar with err -951 which sample shown belows from Informix message logs. Similar error messages are repeating frequently within a second, these will fill up the message logs file and filesystem.
#– Informix message logs –#
10:22:45 listener-thread: err = -951: oserr = 0: errstr = jsmith: Incorrect password or user jsmith is not known on the database server. 10:22:45 listener-thread: err = -951: oserr = 0: errstr = jsmith: Incorrect password or user jsmith is not known on the database server.
The error messages description clearly shows that there are possibilities on,
(1) Userid “jsmith” connect with invalid password or account is locked.
(2) Userid “jsmith” is unknown or not found on database server (not found in /etc/passwd entry).
For my case, it is (2), no userid “jsmaith” found in database host.
The challenge for DBA is to find out which is remote client host attempting an invalid userid connection. Obviously, Informix message logs does not provide remote client host information.
Workaround applies to IDS 10.00, 11.10, 11.50 and above:
Tracing client IP address with xtrace which only available on IDS 10.00 and above.
(1) Ensure IDS instance is On-Line.
$ onstat –
(2) From IDS 10.00 and above, you may find $INFORMIXDIR/bin/xtrace.
(3) Initialize the IP trace components with xtrace.
$ xtrace heavy –c XTF_IPTRACE –f XTF_SYSCALLS
(4) Activate tracing.
$ xtrace on
(5) View client host connection details.
$ xtrace view
(6) You will get following sample output for socket connection,
File Line session
(7) Terminate tracing session.
$ xtrace off
Looking forward:
A feature request has been raised to IBM Informix to include client host/IP in Informix message logs. But there is no schedule on when this feature request will be incorporated into future versions of IDS.