Notes

I’ve been interested in setting up a self-hosted email server for quite sometime. I initially tried Mail-in-a-Box, then NixOS Mailserver and I recently moved to mailcow. Some setup notes for my future self: I used a plain Debian instance on Hetzner. Usually, I create a non-root user and disable password-based SSH, but mailcow wants to run everything as root and so I didn’t bother. I disabled Solr and ClamAV so that I can use a lower memory instance. That’s it! It was smooth sailing other than that.

I setup a Restic Rest Server and this is how I can validte snapshots for it: export RESTIC_REST_USERNAME=a export RESTIC_REST_PASSWORD=b export RESTIC_PASSWORD=c export RESTIC_REPOSITORY='rest:https://restic.a.ketanvijayvargiya.com/a' restic snapshots

How do you pick the right bonds? (Assuming my understanding from random internet forums is accurate) One important aspect is: match bond duration with your investment horizon. For e.g., if you want to invest for the long term (say, 20-30 years down the line), then pick bonds that have ultra-long duration. Also, the duration of a bond fund will remain the same even if your investment horizon changes. (If, let’s say, you reach retirement.) In those cases, you may need to modify the proportion of multiple bond funds to get the desired real duration.

I recently worked with an attorney to setup a revocable trust, here in Washington. Some notes from that: What happens when someone dies and leaves their spouse behind? There is portability or unlimited transfer to spouse at the federal level, i.e. the estate tax limit of the latter automatically doubles. You need a credit shelter trust to achieve the same in Washington. 3 roles in a trust: keep in mind that while you are alive, you are the Grantor, Trustee, and Beneficiary of the Trust. As such, whenever it is talking about any of those roles, it pertains to you. Anything you could do with your assets before you put them into the Trust, you can still do while in the Trust. The restrictions only apply once you are incapacitated or have passed away, and a new person is acting only in the role as Trustee (not Grantor or beneficiary). ...

Event: Community Over Code. Venue: Grand Hyatt Denver, Denver, Colorado. See slides here Abstract: Managing Machine Learning environments is hard: “Where do I install package X from? If I install Y, will it break my current environment or change the package closure in any way? How do I share my code and the corresponding environment with a colleague in a reproducible way? If my code runs locally, how do I ensure it runs as-is in the cloud? How do I safely and easily upgrade the environment at a cadence I want?” ...

I was preparing a technical talk but later discarded it because I decided it wouldn’t have enough depth. Following are my notes from that. Title: Over-engineer your blog with Nix flakes, IaC (i.e. infrastructure as code) and CI/CD Description: Imagine you have a simple system that works with a handful of CLI commands and a few clicks on a cloud provider’s console. What happens if you tinker a little too much? Well, you could transform it into a declaratively defined and fully reproducible system that employs CI/CD. ...

Couple of times, I had an orphan Directory in Proxmox. The solution is simply to remove the corresponding file in /etc/systemd/system. See this. Apparently, this also works for orphan Datastores in Proxmox Backup Server.

It’s fairly easy to limit ZFS’s overall memory usage on Proxmox. Add the following to /etc/modprobe.d/zfs.conf to allocate maximum 16 GB. (Here, 16 * 2^30 = 17179869184.) options zfs zfs_arc_max=17179869184 See this.

ZFS makes it so easy to convert striping to mirroring or vice versa: # Assume "foo" already existed and "bar" is new zpool attach spinning-rust /dev/disk/by-id/foo /dev/disk/by-id/bar zpool detach spinning-rust /dev/disk/by-id/bar No need to initialize the drives or anything - just pass the raw disks.

I was recently contemplating on getting a used enterprise server. And, unlike my previous attempts, I made more progress this time in narrowing down what kind of hardware to buy. So, here are some notes from that: Minimum 2U to keep noise down (and even then it’ll likely be noisy enough to keep in an office). 4Us can be expensive. I may need a closed (but ventilated?) rack to keep the noise down. I can buy it after getting the server and running it for a few days. As of today, Dell’s 13th generation line is ~10 years old and 14th is ~5. However, the power usage of the two should be similar unless I put a lot of load onto the machine. 3.5 vs 2.5 inch drive bays. (The former would be better for me.) Each bay will require a caddy, if I were to put a hard drive in it, or a blank. I should be able to use both SATA and SAS hard drives and I think the former would be cheaper. Reach out to eBay sellers directly and ask for quotes/discounts. For now, I am deciding to continue with my existing consumer-grade PC. Maybe the enterprise server will come later.