i just like this Page … Faces of OpenSource.

Thanks for all the fish, guys !

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sha256: 511dfaf2c20685d4fb80884557bf2efaf1ac7f234d02d25be20687d92cb6ad11

how to update checkmk

let’s assume you already have a running version of checkmk. You should install patches / updated every few month.

Main and Download URL’s

Main URL: https://checkmk.com/de/download?edition=cre&version=stable&dist=debian&os=bullseye

https://download.checkmk.com/checkmk/1.6.0p20/check-mk-raw-1.6.0p20_0.bullseye_amd64.deb

https://download.checkmk.com/checkmk/2.0.0p12/check-mk-raw-2.0.0p12_0.bullseye_amd64.deb

Download and Install Package

Login as Root

v="2.0.0p25"
cd /tmp
wget -O checkmk.deb "https://download.checkmk.com/checkmk/${v}/check-mk-raw-${v}_0.bullseye_amd64.deb"
gdebi checkmk.deb

Update Checkmk

Switch User …

su - mysite

.. Switch User and start Update

omd status
omd version
omd stop
omd update
omd start

Cleanup

exit
omd cleanup

Check Application

Open Browser, check News and Plugins

Need a small and smart utility to manage you ssh keys under linux ? got some scripts and cronjobs which requires an local ssh key ? have a look at keychain !

Install Software

depending on your OS …

macos$ brew install keychain
debian$ sudo apt-get install keychain
openbsd$ pkg_add keychain
freebsd$ pkg install keychain

edit startup Scripts

$HOME/.bashrc $HOME/.bash_profile /etc/profile $HOME/.profile

cat << 'EOF' >> $HOME/.bashrc
# Keychain Startup
eval `keychain --eval id_ed25519`
EOF

check service

$ keychain
$ ssh-add -L

add to .profile

cat << 'EOF' >> .profile

# Keychain Loaded ? Load and show Key ...
eval $(keychain --eval id_ed25519)
echo -e "loaded keys: `ssh-add -L |cut -c 1-12,77-`\n"
EOF

List Keys

keychain --list

List Finterprints (Public Key ?)

$ keychain --list-fp

Set Timeout

Timeout for SSH Agent

Clear History

have you ever checked in some binarys, confidential stuff or something else by mistake ? Git will keep all your history, that’s their design and purpose.

how ever, if you need to cleanup once, here is a short tutorial.

Kill Git Config

cd myrepo
cat .git/config -> note down the url
url=$(git config --get remote.origin.url)
rm -rf .git

Create New Repo

git init
git add .
git commit -m "Removed history, ..."

Push Remote

git remote add origin git@host/yourrepo  <- URL you noted down above
git remote add origin $url
git push -u --force origin master

All in One

_url=$(git remote -v |awk '/fetch/ { print $2 }')
rm -rf .git
git init
git add .
git commit -m "Removed history ..."
git remote add origin ${_url}
git push -u --force origin main
unset _url

and you’re done :)

Some Install Notes

https://checkmk.de/cms_install_packages_debian.html

download and scp check-mk-enterprise-1.6.0p15.demo_0.buster_amd64.deb -> enterprise microkernel, 2 x 10 Hosts download and scp check-mk-raw-1.6.0p15_0.buster_amd64.deb -> raw edition, nagios kernel

ssh root@localhost

apt-get install dpkg-sig libnet-snmp-perl snmp
wget https://checkmk.com/support/Check_MK-pubkey.gpg
gpg --import Check_MK-pubkey.gpg
dpkg-sig --verify /tmp/check-mk-enterprise-1.6.0p15.demo_0.buster_amd64.deb
apt-get install gdebi-core
gdebi /tmp/check-mk-raw-1.6.0p15_0.buster_amd64.deb
omd version

omd create mysite
omd config

oder

omd restore /tmp/mysite.tar.gz

Install v2.0 and migrate existing Config

https://checkmk.de/cms_install_packages_debian.html

download file: check-mk-raw-2.0.0p5_0.buster_amd64.deb

scp check-mk-raw-2.0.0p5_0.buster_amd64.deb host227:/tmp/

Prepare New Host

apt install -y dpkg-sig libnet-snmp-perl snmp

wget https://checkmk.com/support/Check_MK-pubkey.gpg
gpg --import Check_MK-pubkey.gpg
dpkg-sig --verify /tmp/check-mk-raw-2.0.0p5_0.buster_amd64.deb

apt-get install gdebi-core
gdebi /tmp/check-mk-raw-2.0.0p5_0.buster_amd64.deb

omd version

Backup old Server

Backup and copy to new Server

wanna switch a local folder to a remote git repo ?

https://docs.github.com/en/github/using-git/adding-a-remote

GitoLite

create git repo with gitolite (myproject)

add Folder

cd myproject

git init
git remote add origin git@your-git-server:myproject

check Status

git remote -v
git status

add all existing Files, commit and push to remote

git add .
git commit -m "initial commit"
git push --set-upstream origin master

Any Comments ?

sha256: ba5ff311face100add7e9b21efbbb86af94545d3aec2cf8d920ea55ba5353464

debian on apu

boot

menu -> tab

-> debian-installer/i386/linux vga=788 initrd=debian-installer/i386/initrd.gz — console=ttyS0,115200

enter

space

:)

english

country switzerland

nic0

hostname apu005

domain planet

mirror ch -> ftp.ch.debian.org

root password

Partitioning: entire Disk & LVM

Separate /home /var /tmp

survey no

soft: standard system utilities & ssh server

grub yes

braucht ca. 30min !

automated

https://www.debian.org/releases/stable/amd64/apbs02.en.html https://www.debian.org/releases/buster/example-preseed.txt

Packages

apt-get -y install net-tools git htop

Reboot

geht 40 Sekunden

Any Comments ?

sha256: de990ff6c33196dbecc6d133f0fc29686ded54fa7357d30e7dc36a59f0368eb0

Troubleshooting Crontab Problems

Dump the Environment

add this line to root’s crontab

* * * * * env > /root/cronenv

Load the Environment

env - $(cat /root/cronenv) /bin/sh

Run your script

./script_with_env_problems.sh

and check it’s output …

Any Comments ?

sha256: de1667fb4003135420244f48280d72e03d7559b675ab6b4a9c020b0725866525

How to Kickstart a Ubuntu Installation …

edit dhcpd.conf

host ubuntu {
  hardware ethernet 4E:E5:80:xx:xx:xx;
  fixed-address x.x.x.x;
  filename "ubuntu/pxelinux.0";
  next-server x.x.x.200;
}

restart dhcpd

prepare env on tftp server (x.x.x.200)

mkdir -p /tftpboot/ubuntu/
cd /tftpboot/ubuntu/
ftp http://archive.ubuntu.com/ubuntu/dists/bionic-updates/main/installer-amd64/current/images/netboot/netboot.tar.gz
tar xfz netboot.tar.gz

kickstart cfg

put the following file in a webroot available from the client machine

cat <<'EOF' > /var/www/htdocs/ks.cfg
#Generated by Kickstart Configurator
#platform=AMD64 or Intel EM64T

#System language
lang en_US
#Language modules to install
langsupport en_US
#System keyboard
keyboard ch
#System mouse
mouse
#System timezone
timezone Europe/Zurich
#Root password (here 123456)
rootpw --iscrypted $1$r6te7M.4$C55eKRGO2xdodwc3tBe48/
#Initial user
user --disabled
#Reboot after installation
reboot
#Use text mode install
text
#Install OS instead of upgrade
install
#Use Web installation
url --url http://mirror.init7.net/ubuntu/
#System bootloader configuration
bootloader --location=mbr
#Clear the Master Boot Record
zerombr yes
#Partition clearing information
clearpart --all --initlabel
#Disk partitioning information
part swap --size 1024
part /boot --fstype ext4 --size 512
part / --fstype ext4 --size 1 --grow
#System authorization infomation
auth  --useshadow  --enablemd5
#Network information
network --bootproto=dhcp --device=eth0
#Firewall configuration
firewall --disabled
#Do not configure the X Window System
skipx
EOF

start and install client

pxe boot client
on the install screen, press tab and add ‘ks=http://x.x.x.x/ks.cfg’
Enter and wait until done

Any Comments ?

sha256: c58f8a064ddcae5b682a1699da8d10b3abb12ce131826e2a6098ed9b930f4e10

How to configure a Vlan on Linux Mint ?

Wiki

Install vlan

sudo apt-get install vlan

Configuration

root@mint:~# sudo modprobe 8021q

root@mint:~# ifconfig
ens19: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 10.10.18.83  netmask 255.255.255.0  broadcast 10.10.18.255
        inet6 2001:db8:1:2:9506:5fcd:1c61:1279  prefixlen 64  scopeid 0x0<global>
        inet6 2001:db8:1:2:a9:c50b:1348:1ec6  prefixlen 64  scopeid 0x0<global>
        inet6 2001:db8:1:2:e064:b0ec:a08f:7fd8  prefixlen 64  scopeid 0x0<global>
        inet6 2001:db8:1:2:a015:7ec:eef0:1a75  prefixlen 64  scopeid 0x0<global>
        inet6 2001:db8:1:2:a028:b890:ffe8:5231  prefixlen 64  scopeid 0x0<global>
        inet6 2001:db8:1:2:c80:addb:1273:95d5  prefixlen 64  scopeid 0x0<global>
        inet6 fe80::9cc2:b22d:cc15:2946  prefixlen 64  scopeid 0x20<link>
        ether 4e:e5:10:00:06:83  txqueuelen 1000  (Ethernet)
        RX packets 181  bytes 58337 (58.3 KB)
        RX errors 0  dropped 7  overruns 0  frame 0
        TX packets 271  bytes 48413 (48.4 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 138  bytes 13723 (13.7 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 138  bytes 13723 (13.7 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

root@mint:~# vconfig add ens19 158
Added VLAN with VID == 158 to IF -:ens18:-
root@mint:~#

root@mint:~# ip addr add 100.60.100.83/24 dev ens19.158
root@mint:~#

root@mint:~# ip link set up ens19.158
root@mint:~#

Make Permanent

sudo su -c 'echo "8021q" >> /etc/modules'

/etc/network/interfaces
auto ens19.158
iface ens19.158 inet static
    address 100.60.100.83
    netmask 255.255.255.0
    vlan-raw-device ens19.158
    up route add -net 10.0.0.0 netmask 255.0.0.0 gw 100.60.100.1

Any Comments ?

sha256: e69d61613b45307405014943049154d70c8cf140d2a3bcf5bbf7679fbefa798f