I didn’t know the answer either, but usually you can compose solution from solutions of smaller problems.

solution(0): There are no disks. Nothing to do. solution(n): Let’s see if I can use solution(n-1) here. I’ll use solution(n-1) to move all but last disk A->B, just need to rename the pins. Then move the largest disk A->C. Then use solution(n-1) to move disks B->C by renaming the pins. There we go, we have a stack based solution running in exponential time.

It’s one of the easiest problem in algorithm design, but running the solution by hand would give you a PTSD.

Replacing “Programmers:” with “Program:” is more accurate.

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.

I was thinking along the lines of

Plenty of libraries can build the XML using structs/classes. e.g. with serde:

//Data type for row
#[derive(serde::Serialize)]
pub struct Foo {
	pub status: String,
	pub name: String,
}

//Example row
let ent = Foo {
    status: "paid".into(),
    name: "bob".into(),
}

//Example execution
sqlx::query(&serde_xml_rs::to_string(&InsertStmt{
	table: "foo".into(),
	value: &ent,
})?).execute(&conn)?;

Or with jackson-dataformat-xml:

//Data type for row
public class Foo {
    public string status;
    public string name;
}

//Example row
Foo ent = new Foo();
foo.status = "paid";
foo.value = "bob";

//Example execution
XmlMapper xmlMapper = new XmlMapper();
String xml = xmlMapper.writeValueAsString(new InsertStmt("foo", ent));
try (Statement stmt = conn.createStatement()) {
    stmt.executeUpdate(xml)
}

I don’t do JS (yet) but maybe JSX could also do similar things with XML queries.

No more matching $1, $2, … (or ? for mysql) with individual columns, I could dump entire structs/objects into a query and it would work.

Better than parameterized queries. Yes, we have stuff like query("INSERT INTO table(status, name) VALUES ($1, $2);").bind(ent.status).bind(ent.name).execute..., but that’s kind of awful isn’t it? With XML queries, we could use any of the XML libraries we have to create and manipulate XML queries without risking ‘XML injection’. e.g we could convert ordinary structs/classes into column values automatically without having to use any ORM.

I actually like this. This would allow reuse of all the infrastructure we have around XML. No more SQL injection and dealing with query parameters? Sign me up!

We can say default is and and add an Or node for or. Similar to SoP notation, you only write +.

TPM stores the encryption key against secure boot. That way, if attacker disables/alters secure boot then TPM won’t unseal the key. I use clevis to decrypt the drive.

Thank you… I had to learn kubernetes for work and it was around 2 weeks of time investment and then I figured out I could use it to fix my docker-compose pains at home.

If you run a lot of services, I can attest that kubernetes is definitely not overkill, it is a good tool for managing complexity. I have 8 services on a single-node kubernetes and I like how I can manage configuration for each service independent of each other and also the underlying infrastructure.

don’t create one network with Gitlab, Redmine and OpenLDAP - do two, one with Gitlab and OpenLDAP, and one with Redmine and OpenLDAP.

This was the setup I had, but now I am already using kubernetes with no intention to switch back.

I was writing my own compose files, but see my response to a sibling comment for the issue I had.

If one service needs to connect to another service then I have to add a shared network between them. In that case, the services essentially shared a common namespace regarding DNS. DNS resolution would routinely leak from one service to another and cause outages, e.g if I connect Gitlab container and Redmine container with OpenLDAP container then sometimes Redmine’s nginx container would access Gitlab container instead of Redmine container and Gitlab container would access Redmine’s DB instead of its own DB.

I maintained some workarounds, like starting Gitlab after starting Redmine would work fine but starting them other way round would have this issue. But switching to Kubernetes and replacing the cross-service connections with network policies solved the issue for me.

As someone who is operating kubernetes for 2 years in my home server, using containers is much more maintainable compared to installing everything directly on the server.

I tried using docker-compose first to manage my services. It works well for 2-3 services, but as the number of services grew they started to interfere with each other, at that point I switched to kubernetes.

All these are just silly stereotypes that almost nobody fits into.

I just uploaded to Github: https://github.com/akashrawal/nsd4k

I only made it for myself, so expect very rough edges in there.

I run a crude automation on top of OpenSSL CA. It checks for certain labels attached to kubernetes services. Based on that it creates kubernetes secrets containing the generated certificates.

It might be a failing fan. I have an Intel nuc whose fan started sounding like an air raid siren, so I took the fan out, drilled a hole into its bearing and added coconut oil into it. It is working fine till this date, but buying a new fan is probably better.

It is for a challenge, the goal is to build a cloud with workload decoupled from servers decoupled from users who’d deploy the workload, with redundant network and storage, no single choke point for network traffic, and I am trying to achieve this with a small budget.