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diff --git a/README.md b/README.md
@@ -225,8 +225,11 @@ Name | Comments
 
 ## Blogs & News
 
+DevOps & Software Engineering related blogs
+
 Name | Description
 :------|:------:
+[Spacelift Blog](https://spacelift.io/blog) | Excellent tech blog on Kubernetes, Ansible, Terraform and Engineering in general
 [opensource.com](https://opensource.com) | open source related articles including DevOps
 [CooperPress](https://cooperpress.com/publications) | various newsletters on different topics
 [afreshcup](https://afreshcup.com) | "covering Ruby on Rails and whatever else I find interesting in the universe of software"

diff --git a/resources/argocd.md b/resources/argocd.md
@@ -0,0 +1,24 @@
+# ArgoCD
+
+## Commands
+
+* login: `argocd login <ADDRESS>`
+* version: `argocd version`
+
+### Apps
+
+* create an application:
+
+```
+argocd app create {APP NAME} \
+--project {PROJECT} \
+--repo {GIT REPO} \--path {APP FOLDER} \
+--dest-namespace {NAMESPACE} \
+--dest-server {SERVER URL}
+```
+* app list: `argocd app list`
+* app detailed info: `argocd app get <APP NAME>`
+
+* sync app: `argocd app sync <APP NAME>`
+* app history: `argocd app history <APP NAME>`
+* delete app: `argocd app delete <APP NAME>`
diff --git a/resources/containers.md b/resources/containers.md
@@ -65,6 +65,21 @@ Name | Description
 
 * List images: `podman image ls`
 * Pull latest ubuntu image: `podman image pull ubuntu:latest`
+* Remove image from the host: `podman rmi IMAGE`
+* Remove all images: `podman rmi -a` or the more extreme version of it: `podman rmi $(podman images -qa) -f`
+* Login to Red Hat registry: `podman login registry.redhat.io`
+* List all available tags for a given image using the CLI: `podman search --list-tags IMAGE_NAME`
+* List all available tags for a given image using an API request: `curl -Ls https://SERVER/v2/.../tags/list | python -m json.tool`
+* Create an archive from the image: `podman save -o some_image.tar IMAGE`
+* Load image from the archive: `podman load -i some_image.tar`
+* List added/modified/deleted files on container's image filesystem: `podman diff IMAGE_NAME`
+* List of mounted files for a running container: `podman inspect -f "{{range .Mounts}}{{println .Destination}}{{end}}" CONTAINER_NAME/ID`
+* Commit changes to another image: `podman commit EXISTING_IMAGE NEW_IMAGE`
+
+#### Registries
+
+* List all repositories in a registry: `curl -Ls https://SERVER/v2/_catalog?n=`
+* List all repositories in a registry and convert to JSON: `curl -Ls https://SERVER/v2/_catalog?n=3 > | python -m json.tool`
 
 #### Security
 
@@ -103,3 +118,7 @@ chmod 0400 ca-k.pem client-key.pem daemon-key.pem && chmod -v 0444 ca.pem client
 "tlskey": "/home/ubuntu/.docker/key.pem"
 }
 ```
+
+#### Cleanup
+
+* Remove everything: `podman system reset`
diff --git a/resources/git.md b/resources/git.md
@@ -31,6 +31,7 @@ Name | Comments
 * List branches: `git branch`
 * Update based on status of remote branches: `git remote prune origin`
 * Delete local branch: `git branch -d some-branch`
+* What are the changes if merging branch y into x: `git merge-tree $(git merge-base x y) x y`
 
 #### Staging
 

diff --git a/resources/gitops.md b/resources/gitops.md
@@ -0,0 +1 @@
+https://opengitops.dev
diff --git a/resources/kubernetes.md b/resources/kubernetes.md
@@ -105,6 +105,17 @@ Name | Comments
 * Cluster information: `kubectl cluster-info`
 * List nodes: `kubectl get nodes`
 
+### Images
+
+* List all containers images from all namespaces:
+
+```
+kubectl get pods --all-namespaces -o jsonpath="{.items[*].spec.containers[*].image}" |\
+tr -s '[[:space:]]' '\n' |\
+sort |\
+uniq -c
+```
+
 ### Pods
 
 * List of Pods in current namespace: `kubectl get po`
@@ -131,6 +142,10 @@ POD_NAME=$(kubectl get pod \
 | tail -1)
 ```
 
+* Get pods sorted by time creation: `kubectl get pods --sort-by='{.metadata.creationTimestamp}'`
+* Run long/endless running container: `kubectl run test --image ubuntu -- sleep 2000000000`
+* Get a shell access to a container: `kubectl exec --stdin --tty some-shell -- /bin/bash`
+
 ### User
 
 * Creating a new user
@@ -181,3 +196,7 @@ alias kgsvcslwn='watch kubectl get service --show-labels --namespace'
 krmgf nginx-8jk71    # kill pod nginx-8jk71 using grace period 0 and force
 
 ```
+
+### Monitoring
+
+* Install metrics-server using Minikube: `minikube addons enable metrics-server`
diff --git a/resources/linux.md b/resources/linux.md
@@ -10,12 +10,9 @@ Name | Comments
 [Techmint Linux](https://www.tecmint.com/free-online-linux-learning-guide-for-beginners) | Written articles/lessons
 [Linux Survival](https://linuxsurvival.com/linux-tutorial-introduction) | Interactive guide
 [NixCraft](https://www.cyberciti.biz/) | Succinct guides
-
-## Learn Linux - Articles
-
-Name | Comments
-:------|:------:
 [Linux Filesystem Explained](https://www.linux.com/training-tutorials/linux-filesystem-explained) | NSIA
+[Linux SysOps Handbook](https://abarrak.gitbook.io/linux-sysops-handbook) | A study notes book for the common knowledge and tasks of a Linux system admin.
+
 
 ## Linux Internals - Articles
 
@@ -71,7 +68,23 @@ Andrew McNico | [tcpdump](https://www.slideshare.net/j0b1n/tcpdump-hunter?qid=b7
 
 ## Cheat Sheet
 
-#### SElinux
+### Common Operations
+
+* Copy files to a remote host: `rsync -azv dir USER:REMOTE_HOST_ADDR`
+* View file size: `du -sh DIR/FILE`
+
+### Users
+
+* Who is connected: `w`
+
+### Troubleshooting and Debugging
+
+* see list of processes and the CPU and memory the consume: `top`
+* show how long the server is up running: `uptime`
+* List open files: `lsof`
+* List open connections: `lsof -i`
+
+### SElinux
 
 Get SElinux denials
 
@@ -81,7 +94,11 @@ semodule -DB
 sudo ausearch -m avc -m user_avc -m selinux_err -m user_selinux_err -i -ts today
 ```
 
-#### Tmux
+### Communication
+
+* Broadcast a message to everyone: `wall`
+
+### Tmux
 
 * Join a session `tmux a`
 * Attach to existing session: `tmux attach -t <SESSION_NAME>`
@@ -111,13 +128,19 @@ sudo ausearch -m avc -m user_avc -m selinux_err -m user_selinux_err -i -ts today
 * Sort files by size: `ls -l | sort -nk5`
 * Find broken links: `find /some/path -type l -exec test ! -e {} \; -print`
 
-#### YAML
+### LDAP
+
+* LDAP search for a username: `ldapsearch -x -W -D username`
+* LDAP search for a username specifying DC and ldap server: `ldapsearch -x -H ldap://ldap.blabla.com -LLL -b 'dc=DOMAIN,dc=com' "rhatNickName=abregman"`
+
+### YAML
 
 * Validate YAML file with Ruby: `ruby -ryaml -e "p YAML.load(STDIN.read)" < some_file.yaml`
 * Validate YAML file with Python: `pip install pyyaml; python -c 'import yaml, sys; print(yaml.safe_load(sys.stdin))' < some_file.yaml`
 
-#### Misc
+### Misc
 
+* Random string of 7 characters: `mkpasswd -l 8`
 * Generate 8 digit random number: `shuf -i 9999999-99999999 -n 1`
 
 ## Checklist