Monthly Archives: March 2023

Can ChatGPT steal our (Oracle DBA) job?

I would not say it will steal our job, but it can facilitate in some cases to write small pieces of code without having much to think. Well, help first to be lazy, before getting our job. Last example today:

Request ChatGPT to write a trigger that enables BCT after the database opens.

The power is amazing. After looking at the result, you think about a small detail, ask again and it just answers:

Ask ChatGPT to improve so it triggers only when a switchover happened.

But one must always test carefully the answers. Like this case, where the EVENT_TYPE column does not exist on V$DATAGUARD_STATUS table. No idea how he discovers it. I also got non existing syntax and complex solutions that could be easily made simpler.

Root mailbox huge on Exadata after upgrade to OL7

Finally I got to work a bit more with an Exadata. And finding its unknown “features”.

Our monitoring just detected that “/ diskspace 6% free (1.9/23.5 GB) (DiskWarning)”. Looking for the guilty folder or file, I end up here:

# for d in /*; do egrep " ${d} " /proc/mounts > /dev/null || du -sh ${d}; done
15G     /var

# cd /var/
# du -hs * | sort -h
12G     spool

# cd spool/
# du -hs * | sort -h
12G     mail

# cd mail/
# du -hs * | sort -h
12G     root

The huge file was /var/spool/mail/root – the mailbox of the root user.

Trying to open it, just created another small problem:

# mail
/tmp: No space left on device

(parenthesis here: on this Exadata VM we have DBFS running. The check done by the CRS for the DBFS – official script -, also writes to /tmp. If /tmp is full when the DBFS check runs, it fails, and the clusterware moves DBFS to another node. Goldengate, which was using DBFS, just crashed)

The root mailbox is just a text file, so using other tools I saw that is full of emails that come from “0logwatch”. This matches something in cron.daily:

# ls -l /etc/cron.daily/

-rwx------ 1 root root  408 Apr 15  2022 0logwatch

Looking on Metalink, quickly we end up on this note:

Output of Daily Cronjob 0logwatch Sent to Mail instead of Saving to File on Oracle Linux 7 (Doc ID 2564364.1)

The problem comes from an Exadata update, which did not care about syntax change of the /etc/logwatch/conf/logwatch.conf file with OL7. What is a pity, is that later Exadata patches did not seem to care of fixing that.