Useful RAID commands :

# Conf mdadm
cat /etc/mdadm.conf

# Current md stats
cat /proc/mdstat

# detail on a MD device :
mdadm --query --detail /dev/md3

# detail on partition
mdadm --examine /dev/sda3

Complete with OVH RAID help

# Copy partition table from safe disk to new disk (for GPT partition - see fdisk -l)
sgdisk -R /dev/newdisk /dev/safedisk

# afterwards, you have to randomize the GUID on the new hard disk to ensure that they are unique (from [howto forge](https://www.howtoforge.com/tutorial/linux-raid-replace-failed-harddisk/))
sgdisk -G /dev/sdb

# check partitions are copied 
sgdisk -p /dev/safedisk
sgdisk -p /dev/newdisk

# Add each partition to RAID cluster :
mdadm --manage /dev/mdX2 --add /dev/newdiskX2
mdadm --manage /dev/mdX1 --add /dev/newdiskX1

# follow reconstruction with 
mdam --detail /dev/mdX
or 
cat /proc/mdstat
#  Rebuild Status : 21% complete

Outils pratiques :

https://it-tools.tech/

https://lehollandaisvolant.net/tout/tools/

Pour nettoyer entre autre les historiques des fichiers LFS :

1. Lister les fichiers LFS

git lfs ls-files -a -s

2. download jar
3. create a clean copy the repo (git clone)
4. execute :

java -jar bfg-1.14.0.jar --delete-files database-hpa.tar.gz  hpa-portal
git reflog expire --expire=now --all && git gc --prune=now --aggressive

Pire design de réglage de volume, il y en a qui sont vraiment terrible :) Beaucoup de random, mais ce ne sont pas les mieux.

orginalement reddit (bien sur) :

https://www.reddit.com/r/ProgrammerHumor/comments/6evbfd/who_can_make_the_best_volume_slider/?sort=top

(via évidemment https://sebsauvage.net/links/?e0Quog)

Error in subbash :

export extractor_version=$(cd extractor; mvn help:evaluate -Dexpression=project.version -q -DforceStdout)

result in output contains colors output :

1.0'$'\033''[0m.tar.gz'

Remove it with :

./somescript | sed -r "s/\x1B\[([0-9]{1,3}(;[0-9]{1,2};?)?)?[mGK]//g"

Dump cache values

unbound-control dump_cache 

Installation :
(https://memo-linux.com/debian-installer-le-serveur-dns-unbound/)

apt install unbound
cd /var/lib/unbound/ 
wget ftp://ftp.internic.net/domain/named.cache
mv named.cache root.hints && chown unbound:unbound root.hints
mv /etc/unbound/ 
unbound.conf.d/root-auto-trust-anchor-file.conf root-auto-trust-anchor-file.conf.original
mkdir /var/log/unbound
chown unbound: /var/log/unbound
# modify apparmor (see at the end)
systemctl restart unbound

Configuration file:

server:
statistics-interval: 0
extended-statistics: yes
statistics-cumulative: yes
verbosity: 3
interface: 127.0.0.1
port: 53
do-ip4: yes
do-ip6: yes
do-udp: yes
do-tcp: yes
access-control: 127.0.0.0/8 allow ## j'autorise mon serveur
access-control: 0.0.0.0/0 refuse ## j'interdis tout le reste de         l'Internet !
auto-trust-anchor-file: "/var/lib/unbound/root.key"
root-hints: "/var/lib/unbound/root.hints"
hide-identity: yes
hide-version: yes
harden-glue: yes
harden-dnssec-stripped: yes
use-caps-for-id: yes
cache-min-ttl: 3600
cache-max-ttl: 86400
prefetch: yes
num-threads: 6
msg-cache-slabs: 16
rrset-cache-slabs: 16
infra-cache-slabs: 16
key-cache-slabs: 16
rrset-cache-size: 256m
msg-cache-size: 128m
so-rcvbuf: 1m
unwanted-reply-threshold: 10000
do-not-query-localhost: yes
val-clean-additional: yes
#use-syslog: yes
#val-log-level:2 (0: default, nothing, 2: full)
logfile: /var/log/unbound/unbound.log
harden-dnssec-stripped: yes
cache-min-ttl: 3600
cache-max-ttl: 86400
prefetch: yes
prefetch-key: yes

And an additional apparmor configuration to be able to write in a dedicated file :
(https://b4d.sablun.org/blog/2018-09-27-when-unbound-wont-write-logs/)

vim /etc/apparmor.d/local/usr.sbin.unbound

# Site-specific additions and overrides for usr.sbin.unbound.
# For more details, please see /etc/apparmor.d/local/README.
/var/log/unbound/unbound.log rw,

A tester.
Partage d'écran et prise de commande à distance (dont android)

Sous le coude: Choisir ses clés primaires sous Postgres.

via sebsauvage (https://sebsauvage.net/links/?vtwJpQ)

Open a H2 database :

 java -jar com.h2database.h2-2.1.214.jar

or squirrelSQL

add driver with com.h2database.h2-2.1.214.jar.

Default credentials

login : sa
password : password

UPDATE OCTOER 2022

If you want to quickly start the Restore process and don't care about having that option always enabled, then just fire up the Developer console on the browser and run this while on the Restore page

    var modelimport = new Ai1wm.Import();

var storage = Ai1wm.Util.random(12);
var options = Ai1wm.Util.form('#ai1wm-backups-form').concat({ name: 'storage', value: storage }).concat({ name: 'archive', value: 'REPLACE-WITH-ARCHIVE-NAME'});

// Set global params
modelimport.setParams(options);

// Start import
modelimport.start();

Limits the used bandwidth, specified in Kbit/s.

scp -l 1000 file user@remote:/path/to/dest/

Reminder classloader, classname :

Exit0.class.getSimpleName() = Exit0
Exit0.class.getCanonicalName() = com.gorki.Exit0
<instance>.getClass().getSimpleName() = 
<instance>.getClass().getCanonicalName() = null
<instance>.getClass().getName() = com.gorki.Exit0$1
<instance>.getClass().getTypeName() = com.gorki.Exit0$1
<instance>.getClass().getPackage().getName() = com.gorki
<instance>.getClass().isAnonymousClass() = true

With :

package com.gorki;

import java.util.ArrayList;
import java.util.Random;

public class Exit0 {

    public static void main(String... args) {

        Runnable t = new Runnable() {
            @Override
            public void run() {
            }
        };

        System.out.println("Exit0.class.getSimpleName() = " + Exit0.class.getSimpleName());
        System.out.println("Exit0.class.getCanonicalName() = " + Exit0.class.getCanonicalName());
        System.out.println("<instance>.getClass().getSimpleName() = " + t.getClass().getSimpleName());
        System.out.println("<instance>.getClass().getCanonicalName() = " + t.getClass().getCanonicalName());
        System.out.println("<instance>.getClass().getName() = " + t.getClass().getName());
        System.out.println("<instance>.getClass().getTypeName() = " + t.getClass().getTypeName());
        System.out.println("<instance>.getClass().getPackage().getName() = " + t.getClass().getPackage().getName());
        System.out.println("<instance>.getClass().isAnonymousClass() = " + t.getClass().isAnonymousClass());
    }
}

pop culture

merci sebsauvage (comment souvent)

Search for microsoft activation kit (official online download and installation)

 https://github.com/massgravel/

See licence key at

https://www.cjs-cdkeys.com

Best practices shell, to improve :

When printing error messages, please redirect to stderr.
Use echo 'Something unexpected happened' >&2 for this.

And also :

Use set -o xtrace, with a check on $TRACE env variable.

For copy-paste: if [[ "${TRACE-0}" == "1" ]]; then set -o xtrace; fi.
This helps in debugging your scripts, a lot. Like, really lot.
People can now enable debug mode, by running your script as TRACE=1 ./script.sh instead of ./script.sh.

The problem is most engineers don’t want to do operations work. 

So true ! I'm interested in. I want to know how OPs work. I don't want to do it every day :D

Test htaccess rules

Outil de comparaison voiture électrique/thermique :

https://evfootprint.org/simulator

Epub

Generate a self certificate without adding altName with the IP can lead to an error

The reason this error in java 1.8.0_181 is because this update includes security improvements for LDAP support

-Dcom.sun.jndi.ldap.object.disableEndpointIdentification=true