What is ArgoCD ArgoCD is a declarative, GitOps continuous delivery tool for Kubernetes. Your Git repository is the single source of truth; ArgoCD watches it and continuously syncs the cluster to match the desired state. 1Git repo ──► ArgoCD ──► Kubernetes cluster Key concepts Application — a group of Kubernetes resources described in Git. Project — groups applications and scopes their permissions. Source — the repo to render from (git, helm, kustomize, …). Sync — reconcile the live cluster with the desired state. Install 1kubectl create namespace argocd 2kubectl apply -n argocd \ 3 -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml 4 5# expose the UI 6kubectl port-forward svc/argocd-server -n argocd 8080:443 CLI 1argocd login localhost:8080 2 3argocd app create myapp \ 4 --repo https://github.com/org/repo.git \ 5 --path deploy \ 6 --dest-server https://kubernetes.default.svc \ 7 --dest-namespace default 8 9argocd app list 10argocd app sync myapp 11argocd app get myapp Ops notes With syncPolicy.automated set, ArgoCD re-applies any drift on its own. Don’t commit plaintext secrets to Git — pair ArgoCD with an external secret manager (Vault, sealed-secrets, SOPS/ksops).

Create a small infra for kubernetes 1 #On your Azure CLI 2 az --version # Version expected 2.1.0 or higher 3 4 az group delete --name kubernetes -y 5 6 az group create -n kubernetes -l westeurope 7 8 az network vnet create -g kubernetes \ 9 -n kubernetes-vnet \ 10 --address-prefix 10.240.0.0/24 \ 11 --subnet-name kubernetes-subnet 12 13 az network nsg create -g kubernetes -n kubernetes-nsg 14 15 az network vnet subnet update -g kubernetes \ 16 -n kubernetes-subnet \ 17 --vnet-name kubernetes-vnet \ 18 --network-security-group kubernetes-nsg 19 20 az network nsg rule create -g kubernetes \ 21 -n kubernetes-allow-ssh \ 22 --access allow \ 23 --destination-address-prefix '*' \ 24 --destination-port-range 22 \ 25 --direction inbound \ 26 --nsg-name kubernetes-nsg \ 27 --protocol tcp \ 28 --source-address-prefix '*' \ 29 --source-port-range '*' \ 30 --priority 1000 31 32 az network nsg rule create -g kubernetes \ 33 -n kubernetes-allow-api-server \ 34 --access allow \ 35 --destination-address-prefix '*' \ 36 --destination-port-range 6443 \ 37 --direction inbound \ 38 --nsg-name kubernetes-nsg \ 39 --protocol tcp \ 40 --source-address-prefix '*' \ 41 --source-port-range '*' \ 42 --priority 1001 43 44 az network nsg rule list -g kubernetes --nsg-name kubernetes-nsg --query "[].{Name:name, Direction:direction, Priority:priority, Port:destinationPortRange}" -o table 45 46 az network lb create -g kubernetes --sku Standard \ 47 -n kubernetes-lb \ 48 --backend-pool-name kubernetes-lb-pool \ 49 --public-ip-address kubernetes-pip \ 50 --public-ip-address-allocation static 51 52 az network public-ip list --query="[?name=='kubernetes-pip'].{ResourceGroup:resourceGroup, Region:location,Allocation:publicIpAllocationMethod,IP:ipAddress}" -o table 53 #For Ubuntu 54 # az vm image list --location westeurope --publisher Canonical --offer UbuntuServer --sku 18.04-LTS --all -o table 55 # For Redhat 56 # az vm image list --location westeurope --publisher RedHat --offer RHEL --sku 8 --all -o table 57 # => choosen one : 8-lvm-gen2 58 WHICHOS="RedHat:RHEL:8-lvm-gen2:8.5.2022032206" 59 60 # K8s Controller 61 az vm availability-set create -g kubernetes -n controller-as 62 63 for i in 0 1 2; do 64 echo "[Controller ${i}] Creating public IP..." 65 az network public-ip create -n controller-${i}-pip -g kubernetes --sku Standard > /dev/null 66 echo "[Controller ${i}] Creating NIC..." 67 az network nic create -g kubernetes \ 68 -n controller-${i}-nic \ 69 --private-ip-address 10.240.0.1${i} \ 70 --public-ip-address controller-${i}-pip \ 71 --vnet kubernetes-vnet \ 72 --subnet kubernetes-subnet \ 73 --ip-forwarding \ 74 --lb-name kubernetes-lb \ 75 --lb-address-pools kubernetes-lb-pool >/dev/null 76 77 echo "[Controller ${i}] Creating VM..." 78 az vm create -g kubernetes \ 79 -n controller-${i} \ 80 --image ${WHICHOS} \ 81 --nics controller-${i}-nic \ 82 --availability-set controller-as \ 83 --nsg '' \ 84 --admin-username 'kuberoot' \ 85 --admin-password 'Changeme!' \ 86 --size Standard_B2s \ 87 --storage-sku StandardSSD_LRS 88 #--generate-ssh-keys > /dev/null 89 done 90 91 #K8s Worker 92 az vm availability-set create -g kubernetes -n worker-as 93 for i in 0 1; do 94 echo "[Worker ${i}] Creating public IP..." 95 az network public-ip create -n worker-${i}-pip -g kubernetes --sku Standard > /dev/null 96 echo "[Worker ${i}] Creating NIC..." 97 az network nic create -g kubernetes \ 98 -n worker-${i}-nic \ 99 --private-ip-address 10.240.0.2${i} \ 100 --public-ip-address worker-${i}-pip \ 101 --vnet kubernetes-vnet \ 102 --subnet kubernetes-subnet \ 103 --ip-forwarding > /dev/null 104 echo "[Worker ${i}] Creating VM..." 105 az vm create -g kubernetes \ 106 -n worker-${i} \ 107 --image ${WHICHOS} \ 108 --nics worker-${i}-nic \ 109 --tags pod-cidr=10.200.${i}.0/24 \ 110 --availability-set worker-as \ 111 --nsg '' \ 112 --generate-ssh-keys \ 113 --size Standard_B2s \ 114 --storage-sku StandardSSD_LRS \ 115 --admin-username 'kuberoot'> /dev/null \ 116 --admin-password 'Changeme!' \ 117 done 118 119 #Summarize 120 az vm list -d -g kubernetes -o table

OKD vs OpenShift They are essentially the same Kubernetes distribution. OKD — short for “The Community Distribution of Kubernetes that powers Red Hat OpenShift” — is the free, upstream/community edition: the same codebase, community support, and images pulled from quay.io. OpenShift is Red Hat’s enterprise product: OKD plus commercial support, certifications, a longer support lifecycle, Red Hat registries (registry.redhat.io) and OperatorHub access. Day-to-day they are nearly interchangeable — both use the same oc, openshift-install and oc-mirror tooling, and the same install-config.yaml layout. Unless stated otherwise, the notes below apply to both.

A list of nice findings for Kubernetes List all images in Helm chart 1images=$(helm template $helm |yq -N '..|.image? | select(. == "*" and . != null)'|sort|uniq|grep ":"|egrep -v '*:[[:blank:]]' || echo "") upload images listed in an Helm chart 1load_helm_images(){ 2 # look in helm charts 3 for helm in $(ls ../../roles/*/files/helm/*.tgz); do 4 printf "\e[1;34m[INFO]\e[m Look for images in ${helm}...\n" 5 6 images=$(helm template $helm |yq -N '..|.image? | select(. == "*" and . != null)'|sort|uniq|grep ":"|egrep -v '*:[[:blank:]]' || echo "") 7 8 dir=$( dirname $helm | xargs dirname ) 9 10 echo "####" 11 12 if [ "$images" != "" ]; then 13 printf "\e[1;34m[INFO]\e[m Images found in the helm charts: ${images}\n" 14 printf "\e[1;34m[INFO]\e[m Create ${dir}/images images...\n" 15 16 mkdir -p ${dir}/images 17 18 while i= read -r image_name; do 19 archive_name=$(basename -a $(awk -F : '{print $1}'<<<${image_name})); 20 printf "\e[1;34m[INFO]\e[m Pull images...\n" 21 podman pull ${image_name}; 22 printf "\e[1;34m[INFO]\e[m Push ${image_name} in ${dir}/images/${archive_name}\n" 23 podman save ${image_name} --format oci-archive -o ${dir}/images/${archive_name}; 24 done <<< ${images} 25 else 26 printf "\e[1;34m[INFO]\e[m No Images found in the helm charts: $helm\n" 27 fi 28 done 29} Check components version 1function checkComponentsInstall() { 2 componentsArray=("kubectl" "helm") 3 for i in "${componentsArray[@]}"; do 4 command -v "${i}" >/dev/null 2>&1 || 5 { echo "[ERROR] ${i} is required, but it's not installed. Aborting." >&2; exit 1; } 6 done 7} Version comparator 1function checkK8sVersion() { 2 currentK8sVersion=$(kubectl version --short | grep "Server Version" | awk '{gsub(/v/,$5)}1 {print $3}') 3 testVersionComparator 1.20 "$currentK8sVersion" '<' 4 if [[ $k8sVersion == "ok" ]]; then 5 echo "current kubernetes version is ok" 6 else 7 minikube start --kubernetes-version=v1.22.4; 8 fi 9} 10 11 12# the comparator based on https://stackoverflow.com/a/4025065 13versionComparator () { 14 if [[ $1 == $2 ]] 15 then 16 return 0 17 fi 18 local IFS=. 19 local i ver1=($1) ver2=($2) 20 # fill empty fields in ver1 with zeros 21 for ((i=${#ver1[@]}; i<${#ver2[@]}; i++)) 22 do 23 ver1[i]=0 24 done 25 for ((i=0; i<${#ver1[@]}; i++)) 26 do 27 if [[ -z ${ver2[i]} ]] 28 then 29 # fill empty fields in ver2 with zeros 30 ver2[i]=0 31 fi 32 if ((10#${ver1[i]} > 10#${ver2[i]})) 33 then 34 return 1 35 fi 36 if ((10#${ver1[i]} < 10#${ver2[i]})) 37 then 38 return 2 39 fi 40 done 41 return 0 42} 43 44testVersionComparator () { 45 versionComparator $1 $2 46 case $? in 47 0) op='=';; 48 1) op='>';; 49 2) op='<';; 50 esac 51 if [[ $op != "$3" ]] 52 then 53 echo "Kubernetes test fail: Expected '$3', Actual '$op', Arg1 '$1', Arg2 '$2'" 54 k8sVersion="not ok" 55 else 56 echo "Kubernetes test pass: '$1 $op $2'" 57 k8sVersion="ok" 58 fi 59}

The Basics awk is treat each line as a table, by default space are separators of columns. General syntax is awk 'search {action}' file_to_parse. 1# Give the value higher than 75000 in column $4 2df | awk '$4 > 75000' 3 4# Print the all line when column $4 is higher than 75000 5df | awk '$4 > 75000 {print $0}' But if you look for a string, the search need to be included in /search/ or ;search;. When you print $0 represent the all line, $1 first column, $2 second column etc.

Description Buildah: is used to build Open Container Initiative (OCI) format or Docker format container images without the need for a daemon. Podman: provides the ability to directly run container images without a daemon. Podman can pull container images from a container registry, if they are not available locally. Skopeo: offers features for pulling and pushing containers to registries. Moving containers between registries is supported. Container image inspection is also offered and some introspective capabilities can be performed, without first downloading the container itself.

1# see images available on your hosts 2docker image list 3 4# equal to above 5docker images 6REPOSITORY TAG IMAGE ID CREATED SIZE 7httpd latest 6fa26f20557b 45 hours ago 164MB 8hello-world latest 75280d40a50b 4 months ago 1.69kB 9 10# give sha 11docker images --no-trunc=true 12 13# delete unused images 14docker rmi $(docker images -q) 15# delete images without tags 16docker rmi $(docker images | grep "^<none>" | awk '{print $3}')

The Basics 1sed -e '…' -e '…' # Several execution 2sed -i # Replace in place 3sed -r # Play with REGEX 4 5# The most usefull 6sed -e '/^[ ]*#/d' -e '/^$/d' <fich.> # openfile without empty or commented lines 7sed 's/ -/\n -/g' # replace all "-" with new lines 8sed 's/my_match.*/ /g' # remove from the match till end of line 9sed -i '4048d;3375d' ~/.ssh/known_hosts # delete lines Number 10 11# Buffer 12s/.*@(.*)/$1/; # keep what is after @ put it in buffer ( ) and reuse it with $1. 13sed -e '/^;/! s/.*-reserv.*/; Reserved: &/' file.txt # resuse search with & 14 15# Search a line 16sed -e '/192.168.130/ s/^/#/g' -i /etc/hosts # Comment a line 17sed -re 's/^;(r|R)eserved:/; Reserved:/g' file.txt # Search several string 18 19# Insert - add two lines below a match pattern 20sed -i '/.*\"description\".*/s/$/ \n \"after\" : \"network.target\"\,\n \"requires\" : \"network.target\"\,/g' my_File 21 22# Append 23sed '/WORD/ a Add this line after every line with WORD' 24 25# if no occurence, then add it after "use_authtok" 26sed -e '/remember=10/!s/use_authtok/& remember=10/' -i /etc/pam.d/system-auth-permanent

CUE stands for Configure, Unify, Execute Basics Installation 1# Install GO 2GO_VERSION="1.21.0" 3wget https://go.dev/dl/go${GO_VERSION}.linux-amd64.tar.gz 4sudo tar -C /usr/local -xzf go${GO_VERSION}.linux-amd64.tar.gz 5export PATH=$PATH:/usr/local/go/bin 6 7go install cuelang.org/go/cmd/cue@latest 8sudo cp -pr ./go /usr/local/. 9 10# or use Container 11printf "\e[1;34m[INFO]\e[m Install CUElang:\n"; 12podman pull docker.io/cuelang/cue:latest concepts top -> schema -> constraint -> data -> bottom Command 1# import a file 2cue import imageset-config.yaml 3 4# Validate 5cue vet imageset-config.cue imageset-config.yaml 6 7 8* Some basics example 9 10```go 11// This is a comment 12_greeting: "Welcome" // Hidden fields start with "_" 13#project: "CUE" // Definitions start with "#" 14 15message: "\(_greeting) to \(#project)!" // Regular fields are exported 16 17#Person: { 18 age: number // Mandatory condition and must be a number 19 hobbies?: [...string] // non mandatory but if present must be a list of string 20} 21 22// Constrain which call #Person and check if age 23#Adult: #Person & { 24 age: >=18 25} 26 27// =~ match a regular expression 28#Phone: string & =~ "[0-9]+" 29 30// Mapping 31instanceType: { 32 web: "small" 33 app: "medium" 34 db: "large" 35} 36 37server1: { 38 role: "app" 39 instance: instanceType[role] 40} 41 42// server1.instance: "medium" Scripting 1# executable have extension name "_tool.cue" 2 3# usage 4cue cmd prompter 1package foo 2 3import ( 4 "tool/cli" 5 "tool/exec" 6 "tool/file" 7) 8 9// moved to the data.cue file to show how we can reference "pure" Cue files 10city: "Amsterdam" 11 12// A command named "prompter" 13command: prompter: { 14 15 // save transcript to this file 16 var: { 17 file: *"out.txt" | string @tag(file) 18 } // you can use "-t flag=filename.txt" to change the output file, see "cue help injection" for more details 19 20 // prompt the user for some input 21 ask: cli.Ask & { 22 prompt: "What is your name?" 23 response: string 24 } 25 26 // run an external command, starts after ask 27 echo: exec.Run & { 28 // note the reference to ask and city here 29 cmd: ["echo", "Hello", ask.response + "!", "Have you been to", city + "?"] 30 stdout: string // capture stdout, don't print to the terminal 31 } 32 33 // append to a file, starts after echo 34 append: file.Append & { 35 filename: var.file 36 contents: echo.stdout // because we reference the echo task 37 } 38 39 // also starts after echo, and concurrently with append 40 print: cli.Print & { 41 text: echo.stdout // write the output to the terminal since we captured it previously 42 } 43} Sources Offical Documentation

Interesting example from justfile documentation: where it create mktemp and set it in variable then by concatenation you get a full path to the tar.gz. Then the Recipe “publish” create the artifact again and push it to a server. 1tmpdir := `mktemp` # Create a tmp file 2version := "0.2.7" 3tardir := tmpdir / "awesomesauce-" + version 4tarball := tardir + ".tar.gz" # use tmpfile path to create a tarball 5 6publish: 7 rm -f {{tarball}} 8 mkdir {{tardir}} 9 cp README.md *.c {{tardir}} 10 tar zcvf {{tarball}} {{tardir}} 11 scp {{tarball}} me@server.com:release/ 12 rm -rf {{tarball}} {{tardir}} This one can be really usefull to define a default value which can be redefine with env variable:

Shell Variable $$var $$( python -c ‘import sys; print(sys.implementation.name)’ ) Make Variable T ?= foo # give a default value T := $(shell whoami) # execute shell immediately to put in the var PHONY to execute several makefile Example 1 1SUBDIRS = foo bar baz 2 3## dir is a Shell variables 4## SUBDIR and MAKE are Internal make variables 5subdirs: 6 for dir in $(SUBDIRS); do \ 7 $(MAKE) -C $$dir; \ 8 done Example 2 1SUBDIRS = foo bar baz 2 3.PHONY: subdirs $(SUBDIRS) 4subdirs: $(SUBDIRS) 5$(SUBDIRS): 6 $(MAKE) -C $@ 7foo: baz Idea for a testing tools 1git clone xxx /tmp/xxx&& make -C !$/Makefile 2make download le conteneur 3make build le binaire 4make puts it in /usr/local/bin 5make clean 6make help Sources: Tutorials

Deploy a Nexus3 in container on VM Load the image 1podman pull sonatype/nexus3:3.59.0 2podman save sonatype/nexus3:3.59.0 -o nexus3.tar 3podman load < nexus3.tar Create a service inside /etc/systemd/system/container-nexus3.service with content below: 1[Unit] 2Description=Nexus Podman container 3Wants=syslog.service 4 5[Service] 6User=nexus-system 7Group=nexus-system 8Restart=always 9ExecStart=/usr/bin/podman run \ 10 --log-level=debug \ 11 --rm \ 12 -ti \ 13 --publish 8081:8081 \ 14 --name nexus \ 15 sonatype/nexus3:3.59.0 16 17ExecStop=/usr/bin/podman stop -t 10 nexus 18 19[Install] 20WantedBy=multi-user.target

Pypi Repo for airgap env Let’s take as an example py dependencies for Netbox 1# Tools needed 2dnf install -y python3.11 3pip install --upgrade pip setuptool python-pypi-mirror twine 4 5# init mirror 6python3.11 -m venv mirror 7mkdir download 8 9# Get list of Py packages needed 10curl raw.githubusercontent.com/netbox-community/netbox/v3.7.3/requirements.txt -o requirements.txt 11echo pip >> requirements.txt 12echo setuptools >> requirements.txt 13echo uwsgi >> requirements.txt 14 15# Make sure repository CA is installed 16curl http://pki.server/pki/cacerts/ISSUING_CA.pem -o /etc/pki/ca-trust/source/anchors/issuing.crt 17curl http://pki.server/pki/cacerts/ROOT_CA.pem -o /etc/pki/ca-trust/source/anchors/root.crt 18update-ca-trust 19 20 21source mirror/bin/activate 22pypi-mirror download -b -d download -r requirements.tx 23twine upload --repository-url https://nexus3.server/repository/internal-pypi/ download/*.whl --cert /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem 24twine upload --repository-url https://nexus3.server/repository/internal-pypi/ /download/*.tar.gz --cert /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem Then on target host inside /etc/pip.conf :

General concern If you want to move VMs to an another Storage Domain, you need to copy the template from it as well! Remove a disk: 1# IF RHV does not use anymore disk those should appear empty in lsblk: 2lsblk -a 3sdf 8:80 0 4T 0 disk 4└─36001405893b456536be4d67a7f6716e3 253:38 0 4T 0 mpath 5sdg 8:96 0 4T 0 disk 6└─36001405893b456536be4d67a7f6716e3 253:38 0 4T 0 mpath 7sdh 8:112 0 4T 0 disk 8└─36001405893b456536be4d67a7f6716e3 253:38 0 4T 0 mpath 9sdi 8:128 0 0 disk 10└─360014052ab23b1cee074fe38059d7c94 253:39 0 100G 0 mpath 11sdj 8:144 0 0 disk 12└─360014052ab23b1cee074fe38059d7c94 253:39 0 100G 0 mpath 13sdk 8:160 0 0 disk 14└─360014052ab23b1cee074fe38059d7c94 253:39 0 100G 0 mpath 15 16# find all disks from LUN ID 17LUN_ID="360014054ce7e566a01d44c1a4758b092" 18list_disk=$(dmsetup deps -o devname ${LUN_ID}| cut -f 2 |cut -c 3- |tr -d "()" | tr " " "\n") 19echo ${list_disk} 20 21# Remove from multipath 22multipath -f "${LUN_ID}" 23 24# remove disk 25for i in ${list_disk}; do echo ${i}; blockdev --flushbufs /dev/${i}; echo 1 > /sys/block/${i}/device/delete; done 26 27# You can which disk link with which LUN on CEPH side 28ls -l /dev/disk/by-* NFS for OLVM/oVirt Since oVirt need a shared stockage, we can create a local NFS to bypass this point if no Storage bay.

Manuals for commands man <cmd> : Open man page of command. space : go ahead page by page. b : go back page by page. q : quit. Enter : go line by line. /<word> : search a word in man. n : go to the next expression that you search. N : go back to search expression. man -k <key word> : look for in all man for your key words. man -k <word1>.*<word2> : “.*” allow to search several words. whatis <cmd> : give short explaination about the command.

Oracle DB Diagram --- config: theme: forest layout: elk --- flowchart TD subgraph s1["Instance DB"] style s1 fill:#E8F5E9,stroke:#388E3C,stroke-width:2px subgraph s1a["Background Processes"] style s1a fill:#FFF9C4,stroke:#FBC02D,stroke-width:1px n5["PMON (Process Monitor)"] n6["SMON (System Monitor)"] n10["RECO (Recoverer Process)"] end subgraph s1b["PGA (Process Global Area)"] style s1b fill:#E3F2FD,stroke:#1976D2,stroke-width:1px n1["Processes"] end subgraph s1c["SGA (System Global Area)"] style s1c fill:#FFEBEE,stroke:#D32F2F,stroke-width:1px subgraph n7["Shared Pool (SP)"] style n7 fill:#F3E5F5,stroke:#7B1FA2,stroke-width:1px n7a["DC (Dictionary Cache)"] n7b["LC (Library Cache)"] n7c["RC (Result Cache)"] end n8["DB Cache (DBC)"] n9["Redo Buffer"] n3["DBWR (DB Writer)"] n4["LGWR (Log Writer)"] n5["PMON (Process Monitor)"] n6["SMON (System Monitor)"] n10["RECO (Recoverer Process)"] end end subgraph s2["Database: Physical Files"] style s2 fill:#FFF3E0,stroke:#F57C00,stroke-width:2px n11["TBS (Tablespaces, files in .DBF)"] n12["Redo Log Files"] n13["Control Files"] n14["SPFILE (Binary Authentication File)"] n15["ArchiveLog files"] end subgraph s3["Operating System"] style s3 fill:#E0F7FA,stroke:#00796B,stroke-width:2px n16["Listener (Port 1521)"] end n3 --> n11 n3 --> n7c n4 --> n12 n6 --> n7a s3 --> s1 s1c <--> n12 s1c <--> n13 s1c <--> n14 n7b <--> n7c classDef Aqua stroke-width:1px, stroke-dasharray:none, stroke:#0288D1, fill:#B3E5FC, color:#01579B classDef Yellow stroke-width:1px, stroke-dasharray:none, stroke:#FBC02D, fill:#FFF9C4, color:#F57F17 classDef Green stroke-width:1px, stroke-dasharray:none, stroke:#388E3C, fill:#C8E6C9, color:#1B5E20 classDef Red stroke-width:1px, stroke-dasharray:none, stroke:#D32F2F, fill:#FFCDD2, color:#B71C1C class n11,n12,n13,n14,n15 Aqua class n5,n6,n10 Yellow class n1 Green class n7,n8,n9,n3,n4 Red Explanation An Oracle server includes an Oracle Instance and an Oracle Database.

What is Cert-Manager cert-manager automates the management of X.509 certificates inside Kubernetes via CRDs — it requests, issues, renews and rotates certificates automatically. Key concepts Issuer — a namespaced certificate signer. ClusterIssuer — a cluster-wide signer. Certificate — asks cert-manager to obtain a cert for a name. Supported backends: ACME (Let’s Encrypt), self-signed, CA, Vault, Venafi, … Install (helm) 1helm repo add jetstack https://charts.jetstack.io 2helm repo update 3helm upgrade --install cert-manager jetstack/cert-manager \ 4 --namespace cert-manager --create-namespace \ 5 --set installCRDs=true Example: self-signed issuer 1apiVersion: cert-manager.io/v1 2kind: ClusterIssuer 3metadata: 4 name: selfsigned 5spec: 6 selfSigned: {} 1apiVersion: cert-manager.io/v1 2kind: Certificate 3metadata: 4 name: example-tls 5spec: 6 secretName: example-tls 7 dnsNames: 8 - example.com 9 issuerRef: 10 name: selfsigned 11 kind: ClusterIssuer Useful commands 1kubectl get certificate -A 2kubectl get certificaterequest -A 3kubectl describe certificate <name> -n <ns> 4 5# manual renewal (normally automatic) 6cmctl renew <name> -n <ns> Ops notes Cert-Manager stores the TLS key/cert in a <name> secret, ready for Ingress. kubectl get challenges is the first place to look for ACME/Let’s Encrypt failures.

Tar - “tape archiver” Preserve files permissions and ownership. The Basics 1# Archive 2tar cvf my_archive.tar <file1> <file2> </dir/folder/> 3 4## Archive and compress with zstd everything in the current dir and push to /target/dir 5tar -I zstd -vcf archive.tar.zstd -C /target/dir . 6 7# Extract 8tar xvf my_archive.tar 9 10# Extract and push to target dir 11tar -zxvf new.tar.gz -C /target/dir Other useful options • t : list archive’s content. • T : archive list given by a file. • P : preserve absolute path (useful for backing up /etc). • X : exclude. • z : gunzip compression. • j : bzip2 compression. • J : lzma compression.

Troubleshooting 1sudo realm list 2authselect current 3sssctl domain-list 4sssctl config-check 5getent -s files passwd 6getent -s sss passwd user 7getent passwd 8dig -t SRV _ldap._tcp.example.com 9sssctl user-checks toto -s sshd -a auth SSSD process config to link to AD Prerequisites : Need port 369 and 3268 for RHEL8 : 1dnf -y install realmd adcli sssd oddjob oddjob-mkhomedir samba-common-tools krb5-workstation authselect-compat 2 3realm discover example.com 4realm join example.com -U svc-sssd --client-software=sssd --os-name=RedHat --os-version=8 5 6sudo authselect select sssd with-mkhomedir 7sudo systemctl enable --now oddjobd.service inside /etc/sssd/sssd.conf 1[sssd] 2services = nss, pam, ssh, sudo 3domains = example.com 4config_file_version = 2 5default_domain_suffix = example.com 6 7[domain/example.com] 8default_shell = /bin/bash 9override_shell = /bin/bash 10 11ad_domain = example.com 12krb5_realm = example.com 13realmd_tags = manages-system joined-with-adcli 14cache_credentials = True 15id_provider = ad 16krb5_store_password_if_offline = True 17ldap_id_mapping = True 18ldap_user_objectsid = objectSid 19ldap_group_objectsid = objectSid 20ldap_user_primary_group = primaryGroupID 21 22use_fully_qualified_names = True 23fallback_homedir = /home/%u 24 25access_provider = ad 26ldap_access_order=filter,expire 27ldap_account_expire_policy = ad 28ad_access_filter = (memberOf=CN=INTERNAL Team,OU=team-platform,OU=test-groups,DC=example,DC=com) 29 30 31[nss] 32homedir_substring = /home 33 34[pam] 35pam_pwd_expiration_warning = 7 36pam_account_expired_message = Account expired, please contact AD administrator. 37pam_account_locked_message = Account locked, please contact AD administrator. 38pam_verbosity = 3 39 40[ssh] 41 42[sudo] Reload config: 1sss_cache -E; systemctl restart sssd ; sss_cache -E 2systemctl status sssd define sudoers rights /etc/sudoers.d/admin : 1%EXAMPLE.COM\\internal\ team ALL=(ALL) ALL reload sudoers rights: 1realm permit -g 'internal team@example.com'

Some time ago, I made a small shell script to handle Vault on a cluster kubernetes. For documentation purpose. Install Vault with helm 1#!/bin/bash 2 3## Variables 4DIRNAME=$(dirname $0) 5DEFAULT_VALUE="vault/values-override.yaml" 6NewAdminPasswd="PASSWORD" 7PRIVATE_REGISTRY_USER="registry-admin" 8PRIVATE_REGISTRY_PASSWORD="PASSWORD" 9PRIVATE_REGISTRY_ADDRESS="registry.example.com" 10DOMAIN="example.com" 11INGRESS="vault.${DOMAIN}" 12 13if [ -z ${CM_NS+x} ];then 14 CM_NS='your-namespace' 15fi 16 17if [ -z ${1+x} ]; then 18 VALUES_FILE="${DIRNAME}/${DEFAULT_VALUE}" 19 echo -e "\n[INFO] Using default values file '${DEFAULT_VALUE}'" 20else 21 if [ -f $1 ]; then 22 echo -e "\n[INFO] Using values file $1" 23 VALUES_FILE=$1 24 else 25 echo -e "\n[ERROR] No file exist $1" 26 exit 1 27 fi 28fi 29 30## Functions 31function checkComponentsInstall() { 32 componentsArray=("kubectl" "helm") 33 for i in "${componentsArray[@]}"; do 34 command -v "${i}" >/dev/null 2>&1 || 35 { echo "${i} is required, but it's not installed. Aborting." >&2; exit 1; } 36 done 37} 38 39function createSecret() { 40kubectl get secret -n ${CM_NS} registry-pull-secret --no-headers 2> /dev/null \ 41|| \ 42kubectl create secret docker-registry -n ${CM_NS} registry-pull-secret \ 43 --docker-server=${PRIVATE_REGISTRY_ADDRESS} \ 44 --docker-username=${PRIVATE_REGISTRY_USER} \ 45 --docker-password=${PRIVATE_REGISTRY_ADDRESS} 46} 47 48function installWithHelm() { 49helm dep update ${DIRNAME}/helm 50 51helm upgrade --install vault ${DIRNAME}/helm \ 52--namespace=${CM_NS} --create-namespace \ 53--set global.imagePullSecrets.[0]=registry-pull-secret \ 54--set global.image.repository=${PRIVATE_REGISTRY_ADDRESS}/hashicorp/vault-k8s \ 55--set global.agentImage.repository=${PRIVATE_REGISTRY_ADDRESS}/hashicorp/vault \ 56--set ingress.hosts.[0]=${INGRESS} \ 57--set ingress.enabled=true \ 58--set global.leaderElection.namespace=${CM_NS} 59 60echo -e "\n[INFO] sleep 30s" && sleep 30 61} 62 63checkComponentsInstall 64createSecret 65installWithHelm Init Vault on kubernetes Allow local kubernetes to create and reach secret on the Vault

Package with pip3 1pip3 freeze netaddr > requirements.txt 2pip3 download -r requirements.txt -d wheel 3mv requirements.txt wheel 4tar -zcf wheelhouse.tar.gz wheel 5tar -zxf wheelhouse.tar.gz 6pip3 install -r wheel/requirements.txt --no-index --find-links wheel Package with Poetry 1curl -sSL https://install.python-poetry.org | python3 - 2poetry new rp-poetry 3poetry add ansible 4poetry add poetry 5poetry add netaddr 6poetry add kubernetes 7poetry add jsonpatch 8poetry add `cat ~/.ansible/collections/ansible_collections/kubernetes/core/requirements.txt` 9 10poetry build 11 12pip3 install dist/rp_poetry-0.1.0-py3-none-any.whl 13 14poetry export --without-hashes -f requirements.txt -o requirements.txt Push to Nexus 1poetry config repositories.test http://localhost 2poetry publish -r test Images Builder 1podman login registry.redhat.io 2podman pull registry.redhat.io/ansible-automation-platform-22/ansible-python-base-rhel8:1.0.0-230 3 4pyenv local 3.9.13 5python -m pip install poetry 6poetry init 7poetry add ansible-builder

Unicode with With echo echo $’\xae’ = “®” Digraphs in VIM Vim has a special shorthand for entering characters with diacritical marks. If you need some familiar variant of a Latin alphabet character you’ll be able to input it with the digraph system. Digraph input is started in insert or command mode (but not normal mode) by pressing Ctrl-k, then two printable characters in succession. The first is often the “base” form of the letter, and the second denotes the appropriate embellishment.

Specific to RHEL 1# Create a trust zone for the two interconnect 2sudo firewall-cmd --permanent --zone=trusted --add-source=10.42.0.0/16 #pods 3sudo firewall-cmd --permanent --zone=trusted --add-source=10.43.0.0/16 #services 4sudo firewall-cmd --reload 5sudo firewall-cmd --list-all-zones 6 7# on Master 8sudo rm -f /var/lib/cni/networks/cbr0/lock 9sudo /usr/local/bin/k3s-killall.sh 10sudo systemctl restart k3s 11sudo systemctl status k3s 12 13# on Worker 14sudo rm -f /var/lib/cni/networks/cbr0/lock 15sudo /usr/local/bin/k3s-killall.sh 16sudo systemctl restart k3s-agent 17sudo systemctl status k3s-agent Check Certificates 1# Get CA from K3s master 2openssl s_client -connect localhost:6443 -showcerts < /dev/null 2>&1 | openssl x509 -noout -enddate 3openssl s_client -showcerts -connect 193.168.51.103:6443 < /dev/null 2>/dev/null|openssl x509 -outform PEM 4openssl s_client -showcerts -connect 193.168.51.103:6443 < /dev/null 2>/dev/null|openssl x509 -outform PEM | base64 | tr -d '\n' 5 6# Check end date: 7for i in `ls /var/lib/rancher/k3s/server/tls/*.crt`; do echo $i; openssl x509 -enddate -noout -in $i; done 8 9# More efficient: 10cd /var/lib/rancher/k3s/server/tls/ 11for crt in *.crt; do printf '%s: %s\n' "$(date --date="$(openssl x509 -enddate -noout -in "$crt"|cut -d= -f 2)" --iso-8601)" "$crt"; done | sort 12 13# Check CA issuer 14for i in $(find . -maxdepth 1 -type f -name "*.crt"); do openssl x509 -in ${i} -noout -issuer; done Rancher 1# Rancher local install - for example on WSL 2sudo podman run --privileged -d --restart=unless-stopped -p 80:80 -p 443:443 rancher/rancher 3sudo podman ps 4sudo podman logs 74533d50d991 2>&1 | grep "Bootstrap Password:"

install Pfsense VM Download from Netgate website (account requested) Make network config Important note: no need to prepare NetworkManager config, KVM will handle creation of the bridge. Also note that dns enable is set to disables the use of libvirts DHCP server (pfsense is taking over). 1cat > pfsense.xml << EOF 2<network> 3 <name>pfsense-router</name> 4 <uuid></uuid> 5 <forward mode='nat'> 6 </forward> 7 <bridge name='virbr1' stp='on' delay='0'/> 8 <dns enable='no'/> 9 <ip address='192.168.123.1' netmask='255.255.255.0'> 10 </ip> 11</network> 12EOF 13 14sudo virsh net-define pfsense.xml 15sudo virsh net-start pfsense-router 16sudo virsh net-autostart pfsense-router 17 18# Give qemu ACL 19echo "allow all" | sudo tee /etc/qemu-kvm/${USER}.conf 20echo "include /etc/qemu-kvm/${USER}.conf" | sudo tee --append /etc/qemu/bridge.conf 21sudo chown root:${USER} /etc/qemu-kvm/${USER}.conf 22sudo chmod 640 /etc/qemu-kvm/${USER}.conf 23 24# Check network 25nmcli con show --active 26sudo virsh net-list --all 27sudo virsh net-edit pfsense-router 28sudo virsh net-info pfsense-router 29sudo virsh net-dhcp-leases pfsense-router Create and Run Pfsense VM 1# Create pfsense vm 2virt-install \ 3--name pfsense --ram 2048 --vcpus 2 \ 4--disk $HOME/pfsense/disk0.qcow2,size=12,format=qcow2 \ 5--cdrom $HOME/pfsense/netgate-installer-amd64.iso \ 6--network bridge=virbr0,model=e1000 \ 7--network bridge=virbr1,model=e1000 \ 8--graphics vnc,listen=0.0.0.0 --noautoconsole \ 9--osinfo freebsd14.0 \ 10--autostart \ 11--debug 12 13virsh start pfsense Create OKD vm 1virt-install \ 2--name okd --ram 2048 --vcpus 2 \ 3--disk $HOME/okd-latest/disk0.qcow2,size=50,format=qcow2 \ 4--autostart \ 5--cdrom $HOME/okd-latest/rhcos-live.iso \ 6--network bridge=virbr0,model=e1000 \ 7--network bridge=virbr1,model=e1000 \ 8--graphics vnc,listen=0.0.0.0 --noautoconsole \ 9--osinfo detect=on,require=off \ 10--debug 1sudo virt-install -n master01 \ 2 --description "Master01 OKD Cluster" \ 3 --ram=8192 \ 4 --cdrom "$HOME/okd-latest/rhcos-live.iso" \ 5 --vcpus=2 \ 6 --disk pool=default,bus=virtio,size=10 \ 7 --graphics none \ 8 --osinfo detect=on,require=off \ 9 --serial pty \ 10 --console pty \ 11 --network network=openshift4,mac=52:54:00:36:14:e5 1sudo cp {{OKUB_INSTALL_PATH}}/rhcos-live.iso /var/lib/libvirt/images/rhcos-live-{{PRODUCT}}-{{RELEASE_VERSION}}.iso 2export COREOS_INSTALLER="podman run --privileged --pull always --rm -v /dev:/dev -v /var/lib/libvirt/images:/data -w /data quay.io/coreos/coreos-installer:release" 3sudo ${COREOS_INSTALLER} iso kargs modify -a "ip={{IP_MASTERS}}::{{GATEWAY}}:{{NETMASK}}:okub-sno:{{INTERFACE}}:none:{{DNS_SERVER}}" "rhcos-live-{{PRODUCT}}-{{RELEASE_VERSION}}.iso" 4sudo virt-install --name="openshift-sno" \ 5 --vcpus=4 \ 6 --ram=8192 \ 7 --disk path=/var/lib/libvirt/images/sno-{{PRODUCT}}-{{RELEASE_VERSION}}.qcow2,bus=sata,size=120 \ 8 --network network=sno,model=virtio \ 9 --boot menu=on \ 10 --graphics vnc --console pty,target_type=serial --noautoconsole \ 11 --cpu host-passthrough \ 12 --osinfo detect=on,require=off \ 13 --cdrom /var/lib/libvirt/images/rhcos-live-{{PRODUCT}}-{{RELEASE_VERSION}}.iso Checks Pfsense VM 1# Checks 2virsh list 3virsh domifaddr pfsense 4virsh domiflist pfsense 5 6# Connect to console 7virt-viewer --domain-name pfsense Delete Pfsense VM 1virsh destroy pfsense 2virsh undefine pfsense --remove-all-storage 3 4# disk can be deleted only manually 5rm -f ~/pfsense/disk0.qcow2 6 7# delete network 8sudo virsh net-destroy pfsense-router 9sudo virsh net-undefine pfsense-router 10sudo nmcli con del virbr1 11sudo nmcli con del eno1 Create a worker 1# Generate a MAC address 2date +%s | md5sum | head -c 6 | sed -e 's/\([0-9A-Fa-f]\{2\}\)/\1:/g' -e 's/\(.*\):$/\1/' | sed -e 's/^/52:54:00:/';echo 3 4sudo virt-install -n worker03.ocp4.example.com \ 5 --description "Worker03 Machine for Openshift 4 Cluster" \ 6 --ram=8192 \ 7 --vcpus=4 \ 8 --os-type=Linux \ 9 --os-variant=rhel8.0 \ 10 --noreboot \ 11 --disk pool=default,bus=virtio,size=50 \ 12 --graphics none \ 13 --serial pty \ 14 --console pty \ 15 --pxe \ 16 --network bridge=openshift4,mac=52:54:00:95:d4:ed

Prerequisites install KVM on RHEL 1# pre-checks hardware for intel CPU 2egrep -c '(vmx|svm)' /proc/cpuinfo 3lscpu | grep Virtualization 4lsmod | grep kvm 5 6# on RHEL9 Workstation 7sudo dnf install virt-install virt-viewer -y 8sudo dnf install -y libvirt 9sudo dnf install virt-manager -y 10sudo dnf install -y virt-top libguestfs-tools guestfs-tools 11sudo gpasswd -a $USER libvirt 12 13# Helper 14sudo dnf -y install bridge-utils 15 16# Start libvirt 17sudo systemctl start libvirtd 18sudo systemctl enable libvirtd 19sudo systemctl status libvirtd install KVM on Ubuntu 1sudo apt update && sudo apt upgrade -y 2sudo apt install qemu-kvm libvirt-daemon-system libvirt-clients libvirt-daemon virtinst -y 3sudo usermod -aG libvirt $(whoami) 4sudo usermod -aG kvm $(whoami) 5 6# Config 7sudo sed -i 's/^#dynamic_ownership = 1/dynamic_ownership = 1/' /etc/libvirt/qemu.conf 8sudo systemctl restart libvirtd 9 10# Helper 11sudo apt install bridge-utils cpu-checker -y 12 13# Start libvirt 14sudo systemctl start libvirtd 15sudo systemctl enable libvirtd 16sudo systemctl status libvirtd Bonus point: 1sudo apt install cockpit cockpit-machines -y 2sudo systemctl enable --now cockpit.socket 3systemctl status cockpit.socket Then manage your VMs from cockpit: https://localhost:9090 which could be an good alternative to virt-manager.

Basic Checks 1virsh nodeinfo Config a Bridge network Important note that network are created with root user but VM with current user. Non permanent bridge: 1sudo ip link add virbr1 type bridge 2sudo ip link set eno1 up 3sudo ip link set eno1 master virbr1 4sudo ip address add dev virbr1 192.168.2.1/24 Permanent bridge 1sudo nmcli con add ifname virbr1 type bridge con-name virbr1 2sudo nmcli con add type bridge-slave ifname eno1 master virbr1 3sudo nmcli con modify virbr1 bridge.stp no 4sudo nmcli con down eno1 5sudo nmcli con up virbr1 6sudo ip address add dev virbr1 192.168.123.1/24 KVM - Bridge Network 1cat > hostbridge.xml << EOF 2<network> 3 <name>hostbridge</name> 4 <forward mode='bridge'/> 5 <bridge name='virbr1'/> 6</network> 7EOF 8 9sudo virsh net-define hostbridge.xml 10sudo virsh net-start hostbridge 11sudo virsh net-autostart hostbridge Give qemu ACL 1echo "allow all" | sudo tee /etc/qemu-kvm/${USER}.conf 2echo "include /etc/qemu-kvm/${USER}.conf" | sudo tee --append /etc/qemu/bridge.conf 3sudo chown root:${USER} /etc/qemu-kvm/${USER}.conf 4sudo chmod 640 /etc/qemu-kvm/${USER}.conf Check network 1sudo nmcli con show --active 2sudo virsh net-list --all 3sudo virsh net-edit hostbridge 4sudo virsh net-info hostbridge 5sudo virsh net-dhcp-leases hostbridge Check with a small script 1echo -e "\n##### KVM networks #####\n" 2kvm_system_networks_all=$(sudo virsh net-list --all) 3echo -e "Available KVM networks in qemu:///system :\n$kvm_system_networks_all" 4for net in $(sudo virsh net-list --name); do 5 bridge_name=$(sudo virsh net-info --network ${net} | grep Bridge | cut -d":" -f2 | sed 's/^[[:space:]]*//') 6 for br in ${bridge_name}; do 7 br_info=$(ip -br -c address show dev ${br} || echo "No IP address assigned to bridge ${br}") 8 done 9 echo -e "\n\033[1;34m${net}\033[0m have the Bridge: $br_info" 10done 11echo -e "\n" thanks to bridge-utils package installed ealier: 1brctl show Create a VM with this bridge 1virt-install \ 2--name pfsense --ram 2048 --vcpus 2 \ 3--disk $HOME/pfsense/disk0.qcow2,size=12,format=qcow2 \ 4--autostart \ 5--cdrom $HOME/pfsense/netgate-installer-amd64.iso \ 6--network bridge=virbr0,model=e1000 \ 7--network network=hostbridge,model=e1000 \ 8--graphics vnc,listen=0.0.0.0 --noautoconsole \ 9--osinfo freebsd14.0 \ 10--debug Delete network 1sudo virsh net-destroy hostbridge 2sudo virsh net-undefine hostbridge 3sudo nmcli con del virbr1 4sudo nmcli con del eno1 Sources Blog redhat

What is an Operator A controller is a loop that watches Kubernetes objects and reconciles their desired state (the spec) with the actual state (the cluster). An Operator is a controller with operational knowledge baked in: it knows how to install, configure, scale, back up and upgrade an application — the jobs a human admin used to do by hand. 1desired state (CR) ──► reconcile loop ──► actual state (cluster) Classic examples: etcd-operator, prometheus-operator.

Deploy a Quay.io / Mirror-registry on container Nothing original, it just the documentation of redhat, but can be usefull to kickstart a registry. Prerequisites: 10G /home 15G /var 300G /srv or /opt (regarding QuayRoot) min 2 or more vCPUs. min 8 GB of RAM. 1# packages 2sudo yum install -y podman 3sudo yum install -y rsync 4sudo yum install -y jq 5 6# Get tar 7mirror="https://mirror.openshift.com/pub/openshift-v4/clients" 8wget ${mirror}/mirror-registry/latest/mirror-registry.tar.gz 9tar zxvf mirror-registry.tar.gz 10 11# Get oc-mirror 12curl https://mirror.openshift.com/pub/openshift-v4/x86_64/clients/ocp/latest/oc-mirror.rhel9.tar.gz -O 13 14# Basic install 15sudo ./mirror-registry install \ 16 --quayHostname quay01.example.local \ 17 --quayRoot /opt 18 19# More detailed install 20sudo ./mirror-registry install \ 21 --quayHostname quay01.example.local \ 22 --quayRoot /srv \ 23 --quayStorage /srv/quay-pg \ 24 --pgStorage /srv/quay-storage \ 25 --sslCert tls.crt \ 26 --sslKey tls.key 27 28podman login -u init \ 29 -p 7u2Dm68a1s3bQvz9twrh4Nel0i5EMXUB \ 30 quay01.example.local:8443 \ 31 --tls-verify=false 32 33# By default login go in: 34cat $XDG_RUNTIME_DIR/containers/auth.json 35 36# Get IP 37sudo podman inspect --format '{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}' quay-app 38 39#unistall 40sudo ./mirror-registry uninstall -v \ 41 --quayRoot <example_directory_name> 42 43# Info 44curl -u init:password https://quay01.example.local:8443/v2/_catalog | jq 45curl -u root:password https://<url>:<port>/v2/ocp4/openshift4/tags/list | jq 46 47# Get an example of imageset 48oc-mirror init --registry quay.example.com:8443/mirror/oc-mirror-metadata 49 50# Get list of Operators, channels, packages 51oc-mirror list operators --catalog=registry.redhat.io/redhat/redhat-operator-index:v4.14 52oc-mirror list operators --catalog=registry.redhat.io/redhat/redhat-operator-index:v4.14 --package=kubevirt-hyperconverged 53oc-mirror list operators --catalog=registry.redhat.io/redhat/redhat-operator-index:v4.14 --package=kubevirt-hyperconverged --channel=stable unlock user init/admin 1QUAY_POSTGRES=`podman ps | grep quay-postgres | awk '{print $1}'` 2 3podman exec -it $QUAY_POSTGRES psql -d quay -c "UPDATE "public.user" SET invalid_login_attempts = 0 WHERE username = 'init'" Source Mirror-registry

Presentation Gita is opensource project in python to handle a bit number of projects available: Here 1# Install 2pip3 install -U gita 3 4# add repo in gita 5gita add dcc/ssg/toolset 6gita add -r dcc/ssg # recursively add 7gita add -a dcc # resursively add and auto-group based on folder structure 8 9# create a group 10gita group add docs -n ccn 11 12# Checks 13gita ls 14gita ll -g 15gita group ls 16gita group ll 17gita st dcc 18 19# Use 20gita pull ccn 21gita push ccn 22 23gita freeze

Hosted-engine Administration Connect to VM hosted-engine with root and password setup during the install: 1# Generate a backup 2engine-backup --scope=all --mode=backup --file=/root/backup --log=/root/backuplog 3 4# Restore from a backup on Fresh install 5engine-backup --mode=restore --file=file_name --log=log_file_name --provision-db --restore-permissions 6engine-setup 7 8# Restore a backup on existing install 9engine-cleanup 10engine-backup --mode=restore --file=file_name --log=log_file_name --restore-permissions 11engine-setup host Administration Connect in ssh to the Host: 1# Pass a host in maintenance mode manually 2hosted-engine --vm-status 3hosted-engine --set-maintenance --mode=global 4hosted-engine --vm-status 5 6# Remove maintenance mode 7hosted-engine --set-maintenance --mode=none 8hosted-engine --vm-status 9 10# upgrade hosted-engine 11hosted-engine --set-maintenance --mode=none 12hosted-engine --vm-status 13engine-upgrade-check 14dnf update ovirt\*setup\* # update the setup package 15engine-setup # launch it to update the engine /!\ Connect individually to KVM Virtmanager does not work OVirt use libvirt but not like KVM do…