Some follow-up investigation on my part, in regard to my previous post [0]. (Apologies from not simply replying to it and if that screws up threading in the list archives; it looks like my mail is a bit screwy at the moment.)

I forgot to include that my PHP version is 7.1.18.

Assuming that maintenance/update.php is blowing up at the "Adding ipb_id field to table ipblocks" step (since that's where the useful output appeared to stop), I tried to do some digging into where this might be occurring. I found several scripts under maintenance/archives (assuming this is the path for MySQL/MariaDB scripts, since other paths seem to indicate other RDBMSes) where field "ipb_id" was being added to table "ipblocks".

I then took a look at DB backup that I took immediately before attempting the upgrade. Sure enough, column "ipb_id" already exists on table "ipblocks" in my MW 1.30.0 DB. I'm beginning to wonder if the MW 1.31.0 update.php script is attempting to ALTER ipblocks to add ipb_id when it already exists, causing the entire script to bomb. Unfortunately, it looks like update.php is a infinitely spiraling nest of dependencies and call-backs, so I doubt I'll have time to dig any deeper than that.

[0] https://lists.wikimedia.org/pipermail/mediawiki-l/2018-June/047511.html

Jeffrey T. Darlington General Protection Fault https://www.gpf-comics.com/