Nothing like vacation to do and go back to my backup routine and improve it a bit. I mainly put everything in a script, added the the status and scrub of the backup_freenas_rsync script by K. Raquel Sanborn. In the script I do not try to handle all contingencies, simply to be careful, and bail out with a helpful error message if things are strange, assuming that then manual intervention will be required.

The meta info was at the hearth of the NOMAD Archive, as a way to make the data available. The NOMAD meta info is an extensible language independent and format agnostic description of atomistic simulation data. Recently I rewrote the tools to manage the meta info in python 3, improved them and generally tried to take advantage of the lesson learned. pip install meta_into_tools python -m meta_info_tools.meta_tools --help See the meta info page for more details.

Bringing Back Kubernetes The problem Shortly after having had my last day of work some issues came up and the kubernetes cluster went down. I began looking into it (a bit half heartily) and I began noticing some strange random issues. Monitoring the kube-system namespace I saw that flannel issues seemed to crop up quickly. There are several issues open regarding flannel failing #963, 1076,… and initially the real culprit wasn’t clear.

Reinstalling the Kubernetes Production Cluster The main reason for this is a critical Kubernetes bug. Here is a bit a log of what I did (to hopefully help me next time). This is mostly taken from kubernetes doc (1, 2) and tweaks I added. Master node: Basically the same as the Visualization Setup minus the tainting and coredns editing: # disable swap: swapoff -a # comment out swap lines (the command should do it, but I prefer manual edit) # sudo sed -i '/ swap / s/^\(.

Dev Kubernetes reinstall The main reason for this is a critical Kubernetes bug. Here is a bit a log of what I did (to hopefully help me next time). Development cluster extension I installed a new cluster on labdev3, mostly following what I did last time. But labdev4 was having issues, so I asked a clean image. It took a bit to have it up. Here is the process to add it to the Kubernetes cluster.

Kubernetes Kubernetes is central to NOMAD archive and analytics (see /nomad/Kubernetes). Every installation of kubernetes has been quite different (kubernetes evolves quickly). Here is the description of the latest (more manual) installation I did on CentOS for the remote visualization, mainly as a reference for me. This uses kubeadm something that has simplified the installation of kubernetes. update kubeadm (from https://kubernetes.io/docs/setup/independent/install-kubeadm/) cat <<EOF > /etc/yum.repos.d/kubernetes.repo [kubernetes] name=Kubernetes baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64 enabled=1 gpgcheck=1 repo_gpgcheck=1 gpgkey=https://packages.

Punti sparsi di una lezione che ho dato al liceo sulla criptografia Privacy alcuni punti riguardo alla protezione della privacy e alla crittografia Motivazione computer registrano tutto -> mancanza di privacy. Soluzioni: dare le informazioni solo a chi deve riceverle (criptare) dare solo le informazioni necessarie (minimum disclosure arguments) Contesto (e un po' di storia) Antichità - II guerra mondiale Militari, consoli: messaggi cifrati romani p.s. Cesare (shift dell'alfabeto) sparta (striscia di carta su cilindro) in generale permutazione delle lettere II guerra mondiale: Enigma (macchina per cifrare tedesca) .

Crittografia Crittografia a chiave pubblica Idea -> lucchetto (chiave pubblica, privata) Esempio Merkle's puzzles Creare un lucchetto (e una chiave) Creare tantissimi problemi risolvibili (ma che necessitano un po' di tempo) e con come risultato due numeri: n e k in modo che n sia 1 per un problema, 2 per un altro, 3 per un alto ancora,... Tenere a mente che k corrisponde ad ogni n (la chiave privata) Spedire tutti i problemi (ma in sequenza disordinata, casuale) (questa è la chiave pubblica)