Protect against DOS when user has password expired

Hi team, recently we had open a support case TS004670019 on https://www.ibm.com/mysupport/s/case/5003p00002TrWNRAA3/1222wd-db2-taking-too-long-to-login

We had a situation with an automatic process that got it's password expired and begun failing to login to DB2. This process had around 35 threads and all of them where trying to connect to DB2 in an infinite loop. It was having around 5000 authentication requests per minute.

We are using transparent LDAP authentication on AIX, against IBM GSA solution.

After a couple of hours we noticed that DB2 was taking up to 10 minutes to authenticate remote users or local users that where executing "db2 connect to DB_NAME user USER_NAME"

This happened 2 times, first time we have recycled DB2 and it worked fine for some hours, and second time we contacted the client and asked it to stop the processes, after that, DB2 got back to normal.

We where told by support team that there's no way to prevent this ar DB2 level, so better to open a RFE

Also we where trying to implement some monitoring on the diaglogs to block IP's at AIX FW level if they are having a malignant behavior

But I had a problem with messages "-2146500508= SQLZ_RC_PSWEXP" as for this cases when the password is expired, DB2 only reports the User and not the IP into the diaglog.

For others like "-2146500507=SQLZ_RC_BADPSW" or "-2146500502=SQLZ_RC_BADUSR" it reports the user in one message and the IP in the following message, but for *508, it does not have those 2 parts, and we are having some problems detecting from which IP it's coming from, same happened during our problem, we needed to search for the user into ldap, then into w3, then contact the user, then his manager and his team, and toke us like 2 hour to detect the IP where this process was comming from.