CatOps

21 Mar 2023 10:00

​​An article about why you should think twice before using Alpine Linux for your container images.

In nutshell, Alpine uses musl - an implementation of C standard library and many things depend on C standard library including DNS. Since musl doesn’t support DNS over TCP by design, you may get nxdomain errors if the DNS response is more than 512 bytes. And it can happen in Kubernetes.

TBH, Alpine got more stable in the recent years, but still…

The article also provides some alternatives like Wolfi, UBI, and of course, Debian/Ubuntu images. You can use Distroless images as well if you are looking for a small and secure images.

Also, here’s a related Reddit thread, so you can follow the discussion there as well.

#docker #alpine #dns #Kubernetes

CatOps

19 Mar 2023 12:27

The new CatOps Digest is here!

Also, now you can access CatOps newsletter on its own domain: https://newsletter.catops.dev/

Have a nice day 👋

#newsletter #digest

CatOps

16 Mar 2023 09:30

​​You can know inside Terraform is a resource already known during plan stage or will be known only after apply.

That could be a useful hack to avoid "for_each" value depends on resource attributes that cannot be determined until apply error in cases when it could happen and still be able to use nice naming, that does not trigger resource recreation in case of list values change/reorder.

P.S. Not sure that it should be used anywhere at all.

#terraform

CatOps

15 Mar 2023 13:37

Docker Buildkit has a new `COPY --link` feature.

With --link enabled, files added with COPY won't be copied to the previous layer, but a new layer will be created. This can help you to better cache specific things and accelerate your Docker builds.

#docker

CatOps

13 Mar 2023 10:55

​​Today's Donations Monday also goes to Come Back Alive.

Long hands of the Territorial Defense has accumulated 75% of its goal already and 7 regions have closed their goal. Let's help other TRDs complete their objectives as well!

If your region is already all-set, you can always help your neighbors or regions that have fewer donations, or Luhansk, which is the next in line.

#donations #Ukraine

CatOps

10 Mar 2023 15:33

Some time ago (initial commit on the 2nd of May 2021) I started a small side-project - an Awesome List of Ukrainian IT Communities.

There are more than 60 chats, groups, channels, and other resources mentioned there already! And I would appreciate if you help to make this list even more awesome 😎

Your PRs are very welcome!

Also, there is web view if you prefer that.

#culture

CatOps

08 Mar 2023 13:16

​​The recording of our latest voice chat (in Ukrainian) is already available!

This time we were talking about dynamic (and not only) development environments in a cloud.

As usual, you can listen to it on your favorite platforms:

- Spotify
- Apple Podcasts
- Google Podcasts
- Anchor

It is also available on YouTube

Also, I would appreciate it if you rate CatOps on the platform you’re listening to it or put your 👍 on YouTube.

P.S. If you would like to listen to CatOps on a platform that is currently not available, please, let me know in the chat.

#voice #говорилка

CatOps

06 Mar 2023 10:42

​​A technological Donations Monday!

One of the biggest Ukrainian charity foundations - Come Back Alive - has announced a "Cyber Fundraiser" together with Portmone.

The goal is to collect 50M UAH for cyber defense and offense. Currently, only 19% is reached.

#donations #Ukraine

CatOps

01 Mar 2023 11:58

As you may have heard, LastPass had a breach recently.

And it looks like things are chaim_sanders/its-all-bad-news-an-update-on-how-the-lastpass-breach-affects-lastpass-sso-9b4fa64466f6">more complex comparing to the initial “some encrypted data was retrieved”.

According to this article, organizations need to re-onboard their users with SSO provider (if they used any) to ensure that their data is secure in LastPass.

Reddit discussion.

#security

CatOps

27 Feb 2023 14:02

What about the Donations Monday? Well, this time it's not really a foundation or a specific need.

Friends of mine are organizing a special fundraising event - Kubernetes Community Days Ukraine.

As you all know, I don't usually post events' announcements here. Yet, there are exceptions like this.

#donations #Ukraine

CatOps

23 Feb 2023 11:07

Mermaid is a popular tool to create diagrams as code.

It was recently adopted by GitHub, so Mermaid diagrams are automatically displayed as diagrams in the Markdown files (not just in GH, BTW).

We use it in my team a lot and we’re very happy with it!

Here’s a Mermaid cheat sheet, so you can start using it as well (if not already)!

Their official documentation is good as well, although more verbose.

#mermaid #diagrams #github

CatOps

20 Feb 2023 10:51

Getting back to Pavlo and Naya for this Donations Monday.

They need to gather ~ €8100 for this week’s needs. 37% is there, 63% more to go! You know what to do!

- Pavlo’s requisites
- Naya’s requisites

#donations #Ukraine

CatOps

17 Feb 2023 20:07

​​Happy World Cats Day!

Feel free to share your cats in the comments 😏

P.S. It's the first Cats Day in 2023. Up to 7 more are coming

CatOps

16 Feb 2023 10:00

Long time no posts about databases! So, here’s a short story of how Retool migrated their 4TB Postgres database from version 9.6 to 13.

There are a couple of interesting moments in this story:
- “Lift and shift” migrations are still the case. Sometimes it’s better to have a brief period of downtime than risk a migration to fail mid-way
- Cloud solution might not suit or even fail you. Running things in the cloud doesn’t mean that you don’t need to take care of operations whatsoever (especially when it comes to DBs)
- Test using representative workload be it number of requests or the size of DB.
- Even if there’s a tool for a job, it may require some tweaking. Also, sometimes you need to be creative (it’s in the article, they’ve wrote a script to migrate a pair of particularly large tables)
- Write run books :)

I don’t know, how many of you manage databases, but these points are applicable not only to DB migrations I must say.

#databases

CatOps

13 Feb 2023 12:26

​​Donations Monday again!

TBH, I ran out of funds and charities in which I have personal connections.

So, this week I would appreciate it, if you could donate to my "little motherland" - Chernihiv region in the "Long Hands of TRD" project by Come Back Alive foundation! Of course, it's completely Ok if you want to support any other region.

I don't think this foundation require any sort of introduction. So, you know, what to do ;)

P.S. I need to get a new Linktree list with charities. I'll figure it out, I promise.

#donations #Ukraine

CatOps

20 Mar 2023 10:39

Today I want to remind you about the UA Responders foundation that is gathering funds for tactical medicine.

They accept donations via cards, PayPal, and bank transfers. Also, they have a legal entity in Poland, so it's easy to transfer money inside the EU.

#donations #Ukraine

CatOps

17 Mar 2023 12:24

We are not about Marketing, but today's neat peak is:
Bad communication is a key to being remembered by millions of users.

https://www.docker.com/blog/we-apologize-we-did-a-terrible-job-announcing-the-end-of-docker-free-teams/

CatOps

15 Mar 2023 17:20

And not so great news about Docker.

Apparently, Docker is now deleting Open Source organizations.

Basically, the bottom line is that you cannot have an organization on a free account. At the first glance, it looks ok: you want a production-grade SaaS - you pay for it.

The main concern is that there's no official statement from Docker that existing names of such organizations will be locked, so no one can get those except original owners, even with paid accounts. Otherwise, it will open a gate for potential malicious code injection attacks.

#docker

CatOps

14 Mar 2023 10:58

UPD: Ah, sh*t, the Google Form was disabled! I have enabled it, so not it should work as expected.

A new Kubernetes operations survey by CatOps.

Last year I did a Kubernetes operations survey. You can find the results here.

There are things that would be interesting to observe in dynamic. Thus, I decided to make it an annual survey. Last year there were 102 responses, I hope there will be more this year. So, I would very appreciate it, if you could spend a couple of minutes to complete it.

I will share the results here, of course.

#kubernetes #survey

CatOps

12 Mar 2023 16:04

A graphical explainer of how CORS works.

BTW, you can subscribe to this author on Substack. They post very nice zines from time to time!

#cors #web

CatOps

09 Mar 2023 12:53

It’s not a security-focus channel, but I post security-related things from time to time.

There is a book bundle related to cybersecurity on sale at Humble Bundle.

I cannot judge the quality of those books since I’m not an expert. Yet, hopefully it may be interesting to some of you.

#security

CatOps

07 Mar 2023 11:31

Spegel is an in-cluster OCI registry mirror.

It allows nodes to pull images from other nodes in a cluster when a public registry (or your private registry) is not available.

It can also help you to avoid rate limiting and decrease outside traffic if you’re using public registries to pull images in your clusters.

#kubernetes

CatOps

05 Mar 2023 11:38

The first spring issue of the CatOps Newsletter in live!

https://catops.substack.com/p/catops-digest-2023-03-05

#newsletter

CatOps

28 Feb 2023 13:31

Remember those interview questions: “What happens during Linux boot process”, “What happens when you open a link in your browser”, and so on?

Well, the new age has come with questions like “What happens when you you do kubectl <command>”. I was actually asked this question on one of the interviews.

And here’s a guide on GitHub that explains just that.

P.S. Sorry, if I have shared it already. I’m going through some of my old bookmarks and trying to figure out, if there’s anything valuable in there. So, expect some old articles here.

#kubernetes

CatOps

25 Feb 2023 15:29

I don’t want to post anything serious during the weekend. So, here’s a story about how a guy’s Azure account was taken over by his daughter’s school.

I don’t work much with the Microsoft cloud services, so I dunno how common is it.

There’s no morale here. Keep an eye on your Microsoft accounts, I guess ¯\_(ツ)_/¯

CatOps

21 Feb 2023 12:49

We briefly mentioned Crossplane during in our last voice chat. Here is yet another hello word-ish article about Crossplane.

However, what I like about this article that there is a link to a repository with code samples. So, you can examine the code on your own if you want as well as try to run it by yourself.

BTW, I also wrote an article long time ago. Unfortunately, I don’t have a repo with the sample code. I didn’t think of this back then :\

#kubernetes #aws #crossplane

CatOps

19 Feb 2023 12:38

New digest is here!
🎉🎉🎉

#newsletter #digest

CatOps

17 Feb 2023 11:58

​​Finally! I have finished processing the recording of our previous Voice chat!

Last time we were talking about testing of Kubernetes and also what it takes to be a mentor. Audio is in Ukrainian.

I cut too many pauses in the end, so the conversation sounds a bit false in the end. I'll try to do better next time.

You can ~watch~ listen to it on YouTube. Audio is also available on Anchor and Spotify. It should be available soon on Apple Podcasts and Google Podcasts as well, but I'm not sure how often do those services read RSS.

Enjoy!

CatOps

15 Feb 2023 09:58

This is an unplanned post for today, but still.

A critical vulnerability was discovered in MacOS and iOS. That allegedly allows an arbitrary code to be executed with kernel privileges.

Please, make sure to update your OS on Apple devices if you have any. Also, make sure that your IT department is aware of this in case you have Apple devices as work machines.

Patched versions:
- MacOS: 13.2.1
- iOS: 16.3.1

The official statement doesn’t have much info. There is more in this Twitter thread.

#security

CatOps

12 Feb 2023 10:14

I posted about S3 encryption not being a panacea back in a day.

Here’s another article about why AWS S3 encryption by default won’t solve security for you and why you still have to pay attention to the bucket settings.

#aws #security