![](/static/253f0d9b/assets/icons/icon-96x96.png)
![](https://lemmy.ml/pictrs/image/q98XK4sKtw.png)
How I lost a Postgres database:
- Installed Postgres container without configuring a volume
- Made a mental note that I need to configure a volume
- After a few days of usage, restarted the container to configure the volume
- …
- Acceptance
How I lost a Postgres database:
Just did some basic testing on broadcast addresses using socat, broadcast is not working at all with /32 addresses. With /24 addresses, broadcast only reaches nodes that share a subnet. Nodes that don’t share the subnet aren’t reachable by broadcast even when they’re reachable via unicast.
Edit1: Did more testing, it seems like broadcast traffic ignores routing tables.
On 192.168.0.2, I am running socat -u udp-recv:8000,reuseaddr -
to print UDP messages.
Case 1: add 192.168.0.1/24
# ip addr add 192.168.0.1/24 dev eth0
# # Testing unicast
# socat - udp-sendto:192.168.0.2:8000 <<< "Message"
# # Worked
# socat - udp-sendto:192.168.0.255:8000,broadcast <<< "Message"
# # Worked
Case 2: Same as above but delete 192.168.0.0/24 route
# ip addr add 192.168.0.1/24 dev eth0
# ip route del 192.168.0.0/24 dev eth0
# # Testing unicast
# socat - udp-sendto:192.168.0.2:8000 <<< "Message"
2024/02/13 22:00:23 socat[90844] E sendto(5, 0x5d3cdaa2b000, 8, 0, AF=2 192.168.0.2:8000, 16): Network is unreachable
# # Testing broadcast
# socat - udp-sendto:192.168.0.255:8000,broadcast <<< "Message"
# # Worked
Here is a trick that has been tried and tested over the years: Install another distro, and use that to install Arch. This way, you can rely on an already working linux distro till your Arch install works the way you want.
Hmm… Maybe I should adjust my priorities.
I was confused for a moment, because intuitively a CPU fan would look in the same direction as it blows air, so it should look into the heatsink. The fan looking away from the heatsink seems weird to me.
Or the owner installed the fan in the wrong direction.
Technically, containers always run in Linux. (Even on windows/OS X; on those platforms docker runs a lightweight Linux VM that then runs your containers.)
And I wasn’t even using Docker.