Month: September 2024

Removing and Recreating a ZFS Pool

In testing out various ways to achieve disk compression on our PostgreSQL servers, I ended up with a server build with a version of ZFS newer that the package distribution. Which means I needed to recreate the pool to use an older version of ZFS that would be updated as part of the routine patching. Beyond backing up and restoring the data …

# Get rid of existing pool

zpool export pgpool
zpool destroy pgpool
zpool list # this still shows a pool on sdb

# Clear the label

zpool labelclear /dev/sdb

# Didn’t work, so blow away everything on sdb

dd if=/dev/zero of=/dev/sdb bs=1M count=10
wipefs -a /dev/sdb

# Uninstall custom built zfs

cd /root/zfs
make uninstall

Install new ZFS

yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
yum install kernel-devel

yum install https://zfsonlinux.org/epel/zfs-release-2-3$(rpm –eval “%{dist}”).noarch.rpm
dnf config-manager –disable zfs
dnf config-manager –enable zfs-kmod
yum install zfs

# Sign kernel modules

/usr/src/kernels/$(uname -r)/scripts/sign-file sha256 /root/signing/MOK.priv /root/signing/MOK.der /lib/modules/$(uname -r)/extras/zfs/avl/zavl.ko

/usr/src/kernels/$(uname -r)/scripts/sign-file sha256 /root/signing/MOK.priv /root/signing/MOK.der /lib/modules/$(uname -r)/extras/zfs/zfs/zfs.ko

# Reboot

init 6

# And start over — recreate the pool

zpool create pgpool sdb
zfs create pgpool/pgdata
zfs set compression=lz4 pgpool/pgdata
df -h /pgpool/pgdata/

Outnumbered

Any political system requires “buy in” from a very large percentage of those being governed. If the 600,000 people who live in Wyoming thought they had absolutely no say in how the country ran because there are like 8 million people in NYC, 3.5 million in LA. Or even the just about 600,000 people who live in Harrisburg, PA … they don’t have much incentive to peaceful participation in the federal government.

I hear folks in rural parts of Ohio saying the same thing — cannabis will be legalized because of the three C’s (Cinci, Columbus, Cleveland) and they get no say in it. Which made me curious — just how “outnumbered” are these “rural” folks. So I grabbed a list of cities in Ohio with population numbers. Columbus is huge, almost a million people! But there are almost 12 million people in Ohio. So Columbus is just under 8% of the population. Add in Cleveland, and you are up to almost 11% of the population. Keep going — add Cinci to get 13.5%. So the “three C’s” are only 13.5% of the entire population. Toledo gets us over 15%. But these are hardly “bossing everyone else around” percentages. I was down to the 143rd largest city in Ohio — Fostoria with just over 13,000 people — before “cities” account for 50% of the state’s population.

And that assumes 100% of people in urban areas are voting against whatever 100% of these rural people want to see happen. Which is absurd. If 80% of the people in these cities were voting against “the rural way”, we’re adding cities with just under 4,000 residents before we reach 50%.

If 75% are voting against “the rural way”, we’re down to cities with just under 2,000 residents.

While I think Wyoming is probably right — there are enough liberal voters nationally that conservatives would be “outnumbered” without creative districting, over-representation in the senate, and over-representation in the electoral college … the same doesn’t seem to hold true in Ohio.

Hot and Fast Smoked Ribs

Unfortunately, I don’t think we’re going to be able to replicate this exactly — had a bunch of bad temperature probes, so we didn’t realize how hot our smoker was going. We usually do the 3-2-1 thing at like 225F … but the smoker chamber was over 300 degrees. So I did a quick search for “what happens if I smoke my pork ribs at 300” and discovered the hot and fast method. Absolutely no idea that was even a thing!

So we put the ribs on at about 6PM, and it was about 9PM by the time we were eating. I coated them with some spice rubs about an hour before we started cooking. We brushed them with a butter/spice mixture after about an hour of cooking and again about half an hour before pulling them. They were tender but not mush, crispy, tasty (a little too much salt in places, but that’s just the rub), moist, and incredible. While I have no idea what the temperature we cooked these things at, we’re going to try to use this method again after we get some good temp probes.