Moved to Hugo

Moved to Hugo

Hey-hey kids it has been a while, right? Ok, I’m planning to blow the dust off this blog.

Don’t expect anything grandiose yet but I did some homework and moved the blog from Octopress to Hugo so this tin lizzy has a heart of a fighter jet now.

See you soon.

Mt. Shasta in one day 2018/07/01

Mt. Shasta in one day 2018/07/01

As you have noticed I continue to trail off the paved path of the technically inclined blog and venture into hiking/mountaineering Internet backcountry. The reason is I’m an extremely lazy guy who promised to get back to Shasta almost a year ago. It’s time to be back as promised!

Mt. Whitney in one day 2018/06/09

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

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.

These are records from auth log:

/var/log/auth.log

Feb 28 20:21:39 test-instance sshd[21954]: pam_unix(sshd:session): session opened for user ubuntu by (uid=0)
Feb 28 20:21:39 test-instance systemd-logind[756]: New session 75 of user ubuntu.
Feb 28 20:21:39 test-instance sshd[21954]: fatal: fork of unprivileged child failed
Feb 28 20:21:39 test-instance systemd-logind[756]: Removed session 75.

Quite an obscure error message, but smells like cgroup problem. Indeed:

GCE and self hosted k8s 1.6 no route created

GCE and self hosted k8s 1.6 no route created

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

--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.