Received 'Launchpad: Verification of ubuntu.mirror.serversaustralia.com.au-release failed' email

Hello,

We have received an email over the weekend with a subject "Launchpad: Verification of ubuntu.mirror.serversaustralia.com.au-release failed"

The body content states:

A possible failure has been detected on the following mirror:

    ubuntu.mirror.serversaustralia.com.au-release of Ubuntu
    https://launchpad.net/ubuntu/+mirror/ubuntu.mirror.serversaustralia.com.au-release

You are being notified because you are the registered contact in
Launchpad for this mirror.

The mirror content checker failed to locate the minimal set of files a
Ubuntu mirror should contain, and so the mirror has been
temporarily removed from the mirror listings. The log file[1] of the
content check should give you more detailed information of what failed.

Looking at the logs on launchpad from the 17th (https://launchpadlibrarian.net/818613062/ubuntu.mirror.serversaustralia.com.au-release-probe-logfile.txt), it was fetching all releases ok:

Wed Sep 17 20:17:55 2025: Found all ISO images for series The Bionic Beaver and flavour ubuntu.
Wed Sep 17 20:17:55 2025: Found all ISO images for series The Focal Fossa and flavour ubuntu.
Wed Sep 17 20:17:55 2025: Found all ISO images for series The Jammy Jellyfish and flavour ubuntu.
Wed Sep 17 20:17:55 2025: Found all ISO images for series The Noble Numbat and flavour ubuntu.
Wed Sep 17 20:17:55 2025: Found all ISO images for series The Plucky Puffin and flavour ubuntu.
Wed Sep 17 20:17:55 2025: Found all ISO images for series The Trusty Tahr and flavour ubuntu.
Wed Sep 17 20:17:55 2025: Found all ISO images for series The Xenial Xerus and flavour ubuntu.

However then on the 19th and 21st, it is not:

Fri Sep 19 15:59:20 2025: Found all ISO images for series The Questing Quokka and flavour ubuntu.

Sun Sep 21 12:16:29 2025: Found all ISO images for series The Questing Quokka and flavour ubuntu.

Hitting our mirror , I can see all the releases. Kicking off the uburelease job, it completes saying we're up to date. Our xymon monitoring shows no drop in disk usage recently. Is there a way to get more detailed logs of what it is that launchpad/s verifcation process is trying to fetch, and getting a failure on?

Only thing I can think is that a week or two ago, we were getting HAMMERED quite hard, and I dropped the conversation KeepAliveTimeout in apache from 15 seconds to 2 seconds, dropped the main Timeout from 60 seconds to 15 seconds, and seriously dropped the TCP timers (keepalives from 7200s to 300s, FIN timeout from 60s to 15s) - so if the script is making a request, doing some thinking while leaving the socket open, and then going back to make another request on the same socket, it may be getting closed..?

Thanks,

Damien