Monday, February 16, 2026

using Blender to mask bright scenes

Using the same technique as in this previous post, but running on Blender 5 on Mac Mini, 3840x2160 video for Unseen Earth was being rendered at around 15 fps using the ProRES LT codec. Apparently Blender still doesn't have GPU accelerated output codec support, and this is one of the fastest codecs as suggested by ChatGPT. The ProRES LT can then be re-encoded as HEVC using the py-ffmpeg-warp presets

Some more tweaks used were:
  • Multiple masks one atop another to darken extremely bright areas,
  • Using Shift-D to duplicate and then K to cut the mask
  • Using an adjustment layer to increase contrast for the base layer. 

Tuesday, February 10, 2026

Moodle custom reports not being emailed

One of our Moodle instances had this issue being reported, that some newly created custom reports were not being emailed as scheduled. 

The issue was that notifications - including email notifications - were disabled for "Custom report builder schedules" at https://ourserver.org/admin/message.php

After enabling email notifications now for this, "Custom report builder schedules" - the issue was reportedly resolved.

Monday, February 02, 2026

google workspace storage limits

At some point of time, Google Workspace has added a feature to admin.google.com where we can set individual users' storage limits on or off, or change the value on an organizational unit basis. Our current Google workspace now has this feature. One possible catch is that the on/off setting is inherited from the base organizational unit. And it also seems to allow certain users to use 146% of their quota!

Thursday, January 29, 2026

pdfs - make smaller - split or join

There was a requirement to 
1. Make some pdfs smaller than 200 kB to enable uploading on a govt. website
2. Split some pages of the pdf into separate documents.

I used pdfsam - https://pdfsam.org/download-pdfsam-basic/ - to do the separation and merging, 
and the online tool
to compress the pdf size.

Monday, January 26, 2026

troubleshooting dot net server crash on AWS

First, checked if the AWS dashboard has any troubleshooting info for me. But "This user does not have permissions to view AWS Health events" - so I wouldn't get much help from it. Used my earlier post on investigating another Linux server crash as well as ChatGPT for going step by step.

ChatGPT suggested these,
dmesg -T | grep -i oom
journalctl -k | grep -i oom
which had no results. No out-of-memory events seen with those commands.

du -sh /var/log showed 4 GB of journal
journalctl --disk-usage
also showed nearly 4 GB of current and archived logs.

But the system had enough hard disk space left, 
df -h
showed around 30% remaining for the OS disk. 

Checking authentication log with
tail /var/log/auth.log -n4000 | more
found an entry
2026-01-25T14:38:58.186744+05:30 ip-10-0-0-73 systemd-logind[600]: New seat seat0.

But ChatGPT said that's normal, this is apparently done for each login.

Then, copy-pasting the lines just before the crash from syslog, using T13 since the crash was around 13:30

sudo cat  syslog | grep T13 > /home/theadminaccount/syslogsnippet.txt

ChatGPT immediately found the issue. 

ourtestapi.service: Scheduled restart job, restart counter is at 101203
and the reason the service was failing was
The application '/home/thepath/www/ourapi/ourtest.dll' does not exist.

Stopped the service, disabled it, and deleted it from /etc/systemd/system
sudo systemctl stop ourtestapi
sudo systemctl disable ourtestapi
sudo rm /etc/systemd/system/ourtestapi.service

Additionally, as ChatGPT suggested, set up some limits for journalctl's logging by editing
/etc/systemd/journald.conf
and uncommenting these lines and adding values for them - under
[Journal]

SystemMaxUse=900M
SystemKeepFree=1G

RuntimeMaxUse=100M

MaxRetentionSec=30day

and restarted,
sudo systemctl restart systemd-journald

Also vacuumed (removed archived logs) with
sudo journalctl --vacuum-size=3000M
(0 bytes removed - archives were smaller than that)
sudo journalctl --vacuum-size=300M
(500M of archives were removed.)

see who has signed an app on MacOS

Via https://www.youtube.com/watch?v=1UDUtO7LY0k

 Apple Menu > About this Mac > More info button > (Search for System Report on left-hand panel)

In System Report, click the System Report button, then Software > Applications on left-hand panel.

Scroll down to the app in question.

Our self-signed OpenSpace builds show up as "Unknown". Sheepit Mac client also shows "Unknown", so there is a chance that I can edit the manifest of the app to run a script on double-click in order to allow the Mac build to run with a double-click on the app file.

Saturday, January 17, 2026

allowing a non-root user to restart a service on Ubuntu Linux server

As described by ChatGPT, the preferred method was to create sudoers rules for the relevant service(s).

sudo visudo -f /etc/sudoers.d/ourapi

and inside that file, write

deployuser ALL=NOPASSWD: /usr/bin/systemctl restart ourapi.service, \
                         /usr/bin/systemctl start ourapi.service, \
                         /usr/bin/systemctl stop ourapi.service, \
                         /usr/bin/systemctl status ourapi.service

where ourapi.service is the service and deployuser is the non-root user.

Here, we double-checked the location of systemctl using 
which systemctl

After doing this, on logging on as deployuser, we can do things like

sudo systemctl start ourapi.service

where it will prompt for deployuser's password and then carry out the command.

But a caveat - we need to type exactly the same command as mentioned in the custom sudoers file - even equivalent commands like

sudo systemctl start ourapi

will not work unless we add that to the sudoers file also.