OxDEAD Unicornz

Have you ever seen so many?

Mt. Whitney in One Day 2018-06-09

Why this post in this blog? – I am generally trying to keep this blog technically inclined. Researching information on one day mt. Whitney hike I was able to find bits of useful information here and there but no ‘end-to-end product’ so to say. This post is an attempt to decrease amount of googling you need to do. Plus doing this hike in one day wasn’t a cakewalk so quite naturally I need to brag a bit, please bear with me.

Disclaimer – use the information as well as anything you find on the Internet as a baseline. Mountaineering is an inherently dangerous activity. Be prepared, be cautious and be lucky. No book or Internet publication is able to provide you with a hands on experience.

Ubuntu User Hits Thread Number Limit Preventing SSH Login

Recently I was investigating quite an interesting issue – there is Ubuntu based VM our testers run some tests on. It was reported they’re unable to log into the virtual machine. After a brief investigation it became clear the issue is not network or SSH key related.

GCE and Self Hosted K8s 1.6 With Calico/Flannel NoRouteCreated

There is an annoying bug in Kubernetes 1.6 running on GCE with Calico/Flannel networking operating via CNI plugin interface. You may experience same issue if kubelet on your nodes runs with options

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--network-plugin=cni --cloud-provider=gce

When a new node is added to the k8s cluster it’s recognized as ‘Ready’ but no pods except Calico/Flannel pod are being scheduled there.

I’ll Be Back Shasta

Sup guys I’m back and I have something for you nerdy hikers. If you’re impatient enough please feel free to skip to the bottom of the post to get the details.

Few weeks ago I’ve made an attempt to summit mt. Shasta in northern California – from Bunny flats, via Horse camp, 50/50, Helen lake, Red banks. Reached the bottom of Misery hill (4km point) and turned back.

Lessons learned:

Nginx: TLS Termination for RESTful Service Responding in JSON

This is quite common nowadays to have some TLS terminatin reverse proxy in front of your REST API. Nginx is being used frequently for this purpose.

The problem I faced and spent some time trying to resolve is that API backing Nginx responds in JSON, but if something is wrong with the request itself or Nginx can’t reach the backend Nginx returns error page in ‘text/html’.

Basically what I was trying to do is to make nginx respond ‘application/json’ on 502 errors, when no backends is reachable and on 400 errors, when someone tries to get plain HTTP response on 443 port. Other errors are expected to be reported by API itself.

Great Introductory Course on Docker and Kubernetes

Google container engine under the hood. Just in case – Google grants new customers with $300 credit for 2 month of trial to play with cloud services.

Here is another one, straight from developers. You don’t even have to install kubectl, everything runs in a virtual console. Yay!

Bash Chanllenge!

Awesome stuff to check if your BASH scripting skills rusted a bit.