This is great: How to write idempotent Bash scripts. Some highlights for me were `blkid` and `mountpoint`.
Monthly Archives: February 2022
Snap-confine has elevated permissions
I tried to run `chromium` on my Kubuntu 20.04.3 LTS workstation and got the following error:
Snap-confine has elevated permissions and is not confined but should be. Refusing to continue to avoid permission escalation attacks
I found this and this worked for me:
systemctl enable --now apparmor.service systemctl enable --now snapd.apparmor.service
So you want to build an embedded Linux system?
This is an excellent article, I only wish I had time to read it: So you want to build an embedded Linux system?.
Quote for the day: oscilloscope is voltmeter
Over on The difference between a mixed-domain oscilloscope and a mixed-signal oscilloscope:
“An oscilloscope is essentially a sensitive auto-ranging voltmeter.”
Are Mixed Signal (MSO) Oscilloscopes Worth The Money?
The EEVblog guys over on Are Mixed Signal (MSO) Oscilloscopes Worth The Money? says that no, they’re probably not. They are, however, “the duck’s guts”. :)
I made a cable!
Been pottering in my lab:
I have this USB Logic Analyzer which I want to test:
Figured this was a great chance to try out my new XR2206 function generator:
Hmm. Needs power! The XR2206 datasheet said it could support a wide supply range, from 10V to 26V. Figured this was a good chance to try out my new ATX power break out board:
I need a power cable from round lugs on the ATX supply:
to DC male for the function generator:
connected with a good length of wire:
and professionally finished with heat-shrink tubing:
had to break out my soldering station:
and make myself a power cable:
to connect the ATX power supply:
to the function generator:
Testing the logic analyzer can wait for another day. :)
EEVblog #652 – Oscilloscope & Function Generator Termination Demo
Have just discovered EEVblog with this one: EEVblog #652 – Oscilloscope & Function Generator Termination Demo. Interesting stuff! Tip: always use a x10 probe on your scope.
XH-M229 with RD6006W
Got myself an XH-M229 board so I could repurpose an old ATX power supply. Apparently it’s suitable to use 1 amp fuses. Gonna send the 12V rail into my RD6006W bench power supply.
ZFS decuplication
Checking ashift on existing pools
Today I found: Checking ashift on existing pools. In summary:
# zpool get all | grep ashift # zpool get all | less # zdb -C | grep ashift # zdb -C | less # zdb -U /etc/zfs/zpool.cache | less
Per ZFS 101—Understanding ZFS storage and performance you *really* want to make sure your ashift value is aligned with your disk’s sector size. ashift=9 for 512; ashift=12 for 4096; I’ve heard some SSDs can be 8K, but I haven’t been able to confirm for my own disks.