JENKIN CHEATSHEET

Openshift cheatsheet

Openshift Login and Configuration

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#login with a user oc login https://192.168.99.100:8443 -u developer -p developer   #login as system admin oc login -u system:admin   #User Information oc whoami   #View your configuration oc config view   #Update the current context to have users login to the desired namespace: oc config set-context `oc config current-context` --namespace=

Basic Commands

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#Use specific template oc new-app https://github.com/name/project --template=   #New app from a different branch oc new-app --name=html-dev nginx:1.10~https://github.com/joe-speedboat/openshift.html.devops.git#mybranch   #Create objects from a file: oc create -f myobject.yaml -n   #Create or merge objects from file oc apply -f myobject.yaml -n   #Update existing object oc patch svc mysvc --type merge --patch '{"spec":{"ports":[{"port": 8080, "targetPort": 5000 }]}}'   #Monitor Pod status watch oc get pods   #show labels oc get pods --show-labels    #Gather information on a project's pod deployment with node information $ oc get pods -o wide   #Hide inactive Pods oc get pods --show-all=false   #Display all resources  oc get all,secret,configmap   #Get the Openshift Console Address oc get -n openshift-console route console   #Get the Pod name from the Selector and rsh in it POD=$(oc get pods -l app=myapp -o name) oc rsh -n $POD   #exec single command in pod oc exec $POD $COMMAND   #Copy file from myrunning-pod-2 path in the current location oc rsync myrunning-pod-2:/tmp/LogginData_20180717220510.json .   #Read resource schema doc oc explain dc

Image Streams

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#List available IS for openshift project oc get is -n openshift   #Import an image from an external registry oc import-image --from=registry.access.redhat.com/jboss-amq-6/amq62-openshift -n openshift jboss-amq-62:1.3 --confirm   #List available IS and templates oc new-app --list

WildFly application example

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oc create -f https://raw.githubusercontent.com/wildfly/wildfly-s2i/wf-18.0/imagestreams/wildfly-centos7.json oc new-app wildfly~https://github.com/fmarchioni/ocpdemos --context-dir=wildfly-basic --name=wildfly-basic oc expose svc/wildfly-basic

Create app from a Project with Dockerfile

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oc new-build --binary --name=mywildfly -l app=mywildfly   oc patch bc/mywildfly -p '{"spec":{"strategy":{"dockerStrategy":{"dockerfilePath":"Dockerfile"}}}}'       oc start-build mywildfly --from-dir=. --follow   oc new-app --image-stream=mywildfly       oc expose svc/mywildfly

Nodes

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#Get Nodes lits oc get nodes   #Check on which Node your Pods are running oc get pods -o wide   #Schedule an application to run on another Node oc patch dc  myapp -p '{"spec":{"template":{"spec":{"nodeSelector":{"kubernetes.io/hostname": "ip-10-0-0-74.acme.compute.internal"}}}}}'   #List all pods which are running on a Node oc adm manage-node node1.local --list-pods   #Add a label to a Node oc label node node1.local mylabel=myvalue   #Remove a label from a Node oc label node node1.local mylabel-

Storage

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#create a PersistentVolumeClaim (+update the DeploymentConfig to include a PV + update the DeploymentConfig to attach a volumemount into the specified mount-path)    oc set volume dc/file-uploader --add --name=my-shared-storage \ -t pvc --claim-mode=ReadWriteMany --claim-size=1Gi \ --claim-name=my-shared-storage --claim-class=ocs-storagecluster-cephfs \ --mount-path=/opt/app-root/src/uploaded \ -n my-shared-storage   #List storage classes oc -n openshift-storage get sc

Build

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#Manual build from source  oc start-build ruby-ex   #Stop a build that is in progress   oc cancel-build   #Changing the log level of a build: oc set env bc/my-build-name BUILD_LOGLEVEL=[1-5]

Deployment

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#Manual deployment $ oc rollout latest ruby-ex   #Pause automatic deployment rollout oc rollout pause dc $DEPLOYMENT   # Resume automatic deployment rollout oc rollout resume dc $DEPLOYMENT   #Define resource requests and limits in DeploymentConfig oc set resources deployment nginx --limits=cpu=200m,memory=512Mi --requests=cpu=100m,memory=256Mi   #Define livenessProve and readinessProve in DeploymentConfig oc set probe dc/nginx --readiness --get-url=http://:8080/healthz --initial-delay-seconds=10 oc set probe dc/nginx --liveness --get-url=http://:8080/healthz --initial-delay-seconds=10   #Define Horizontal Pod Autoscaler (hpa) oc autoscale dc $DC_NAME --max=4 --cpu-percent=10

Routes

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#Create route  $ oc expose service ruby-ex   #Read the Route Host attribute oc get route my-route -o jsonpath --template="{.spec.host}"

Services

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#Make a service idle. When the service is next accessed will automatically boot up the pods again: $ oc idle ruby-ex   #Read a Service IP oc get services rook-ceph-mon-a --template='{{.spec.clusterIP}}'

Clean up resources

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#Delete all resources oc delete all --all   #Delete resources for one specific app $ oc delete services -l app=ruby-ex $ oc delete all -l app=ruby-ex   #CleanUp old docker images on nodes #Keeping up to three tag revisions 1, and keeping resources (images, image streams and pods) younger than sixty minutes: oc adm prune images --keep-tag-revisions=3 --keep-younger-than=60m   #Pruning every image that exceeds defined limits: oc adm prune images --prune-over-size-limit

Troubleshooting

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#Check status of current project    oc status   #Get events for a project oc get events --sort-by='{.lastTimestamp}'   # get the logs of the myrunning-pod-2-fdthn pod oc logs myrunning-pod-2-fdthn # follow the logs of the myrunning-pod-2-fdthn pod oc logs -f myrunning-pod-2-fdthn # tail the logs of the myrunning-pod-2-fdthn pod oc logs myrunning-pod-2-fdthn --tail=50   #Check the integrated Docker registry logs: oc logs docker-registry-n-{xxxxx} -n default | less   #run cluster diagnostics oc adm diagnostics

Security

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#Create a secret from the CLI and mount it as a volume to a deployment config: oc create secret generic oia-secret --from-literal=username=myuser  --from-literal=password=mypassword oc set volumes dc/myapp --add --name=secret-volume --mount-path=/opt/app-root/  --secret-name=oia-secret

Manage user roles

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oc adm policy add-role-to-user admin oia -n python oc adm policy add-cluster-role-to-user cluster-reader system:serviceaccount:monitoring:default oc adm policy add-scc-to-user anyuid -z default

Misc commands

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#Manage node state oc adm manage node --schedulable=false   #List installed operators oc get csv   #Export in a template the IS, BC, DC and SVC oc export is,bc,dc,svc --as-template=app.yaml   #Show user in prompt function ps1(){    export PS1='[\u@\h($(oc whoami -c 2>/dev/null|cut -d/ -f3,1)) \W]\$ ' }   #backup openshift objects   oc get all --all-namespaces --no-headers=true | awk '{print $1","$2}' | while read obj do   NS=$(echo $obj | cut -d, -f1)   OBJ=$(echo $obj | cut -d, -f2)   FILE=$(echo $obj | sed 's/\//-/g;s/,/-/g')   echo $NS $OBJ $FILE; oc export -n $NS $OBJ -o yaml > $FILE.yml done

Linux Commands Cheat Sheet in Black & White 

Keep this Linux command cheat sheet on your desk printed, I am sure you will learn them quickly and will be a Linux expert very soon. We have added had both pdf and image (png) format of the cheat sheet.
Command are categorized into different sections according to its usage. We have designed the command in white color with black background as we often use on Linux shell. We have added bit color for attraction.
We have grouped Linux commands in the below sections for better understanding.

Linux command cheat sheet

• System
• Hardware
• Users
• File Commands
• Process Related
• File Permission
• Network
• Compression / Archives
• Install Packages
• Install Source
• Search
• Login
• File Transfer
• Directory Traverse

Download your linux commands cheat sheet in pdf format which is updated in 2019. Please keep us posted if you have any suggestions or if you find any command that we missed out.
If you are looking to print Linux commands cheat sheet in A4 size paper its available for download.

1) System

uname	Displays  Linux system information
uname -r	Displays  kernel release information
uptime	Displays how long the system has been running including load average
hostname	Shows the system hostname
hostname -i	Displays the IP address of the system
last reboot	Shows system reboot history
date	Displays current system date and time
timedatectl	Query and change the System clock
cal	Displays the current calendar month and day
w	Displays currently  logged in users in the system
whoami	Displays who you are logged in as
finger username	Displays information about the user

2) Hardware

dmesg	Displays bootup messages
cat /proc/cpuinfo	Displays more information about CPU e.g model, model name, cores, vendor id
cat /proc/meminfo	Displays more information about hardware memory e.g. Total and Free memory
lshw	Displays information about system's hardware configuration
lsblk	Displays block devices related information
free -m	Displays free and used memory in the system (-m flag indicates memory in MB)
lspci -tv	Displays PCI devices in a tree-like diagram
lsusb -tv	Displays USB devices in a tree-like diagram
dmidecode	Displays hardware information from the BIOS
hdparm -i /dev/xda	Displays information about disk data
hdparm -tT /dev/xda <:code>	Conducts a read speed test on device xda
badblocks -s /dev/xda	Tests  for unreadable blocks on disk

3) Users

id	Displays the details of the active user e.g. uid, gid, and groups
last	Shows the last logins in the system
who	Shows who is logged in to the system
groupadd "admin"	Adds the group 'admin'
adduser "Sam"	Adds user Sam
userdel "Sam"	Deletes user Sam
usermod	Used for changing / modifying user information

4) File Commands

ls -al	Lists files - both regular &  hidden files and their permissions as well.
pwd	Displays the current directory file path
mkdir 'directory_name'	Creates a new directory
rm file_name	Removes a file
rm -f filename	Forcefully removes a file
rm -r directory_name	Removes a directory recursively
rm -rf directory_name	Removes a directory forcefully and recursively
cp file1 file2	Copies the contents of file1 to file2
cp -r dir1 dir2	Recursively Copies dir1 to dir2. dir2 is created if it does not exist
mv file1 file2	Renames file1 to file2
ln -s /path/to/file_name   link_name	Creates a symbolic link to file_name
touch file_name	Creates a new file
cat > file_name	Places standard input into a file
more file_name	Outputs the contents of a file
head file_name	Displays the first 10 lines of a file
tail file_name	Displays the last 10 lines of a file
gpg -c file_name	Encrypts a file
gpg file_name.gpg	Decrypts a file
wc	Prints the number of bytes, words and lines in a file
xargs	Executes commands from standard input

5) Process Related

ps	Display currently active processes
ps aux | grep 'telnet'	Searches for the id of the process 'telnet'
pmap	Displays memory map of processes
top	Displays all running processes
kill pid	Terminates process with a given pid
killall proc	Kills / Terminates all processes named proc
pkill process-name	Sends a signal to a process with its name
bg	Resumes suspended jobs in the background
fg	Brings suspended jobs to the foreground
fg n	job n to the foreground
lsof	Lists files that are open by processes
renice 19 PID	makes a process run with very low priority
pgrep firefox	find Firefox process ID
pstree	visualizing processes in tree model

6) File Permission

chmod octal filename	Change file permissions of the file to octal
Example
chmod 777 /data/test.c	Set rwx permissions to owner, group and everyone (everyone else who has access to the server)
chmod 755 /data/test.c	Set rwx to the owner and r_x to group and everyone
chmod 766 /data/test.c	Sets rwx for owner, rw for group and everyone
chown owner user-file	Change ownership of the file
chown owner-user:owner-group file_name	Change owner and group owner of the file
chown owner-user:owner-group directory	Change owner and group owner of the directory

7) Network

ip addr show	Displays IP addresses and all the network interfaces
ip address add 192.168.0.1/24 dev eth0	Assigns IP address 192.168.0.1 to interface eth0
ifconfig	Displays IP addresses of all network interfaces
ping  host	ping command sends an ICMP echo request to establish a connection to server / PC
whois domain	Retrieves more information about a domain name
dig domain	Retrieves DNS information about the domain
dig -x host	Performs reverse lookup on a domain
host google.com	Performs an IP lookup for the domain name
hostname -i	Displays local IP address
wget file_name	Downloads a file from an online source
netstat -pnltu	Displays all active listening ports

8) Compression/Archives

tar -cf home.tar home<:code>	Creates archive file called 'home.tar' from file 'home'
tar -xf files.tar	Extract archive file 'files.tar'
tar -zcvf home.tar.gz source-folder	Creates gzipped tar archive file from the source folder
gzip file	Compression a file with .gz extension

9) Install Packages

rpm -i pkg_name.rpm	Install an rpm package
rpm -e pkg_name	Removes an rpm package
dnf install pkg_name	Install package using dnf utility

10) Install Source (Compilation)

./configure	Checks your system for the required software needed to build the program. It will build the Makefile containing the instructions required to effectively build the project
make	It reads the Makefile to compile the program with the required operations. The process may take some time, depending on your system and the size of the program
make install	The command installs the binaries in the default/modified paths after the compilation

11) Search

grep 'pattern' files	Search for a given pattern in files
grep -r pattern dir	Search recursively for a pattern in a given directory
locate file	Find all instances of the file
find /home/ -name "index"	Find file names that begin with 'index' in /home folder
find /home -size +10000k	Find files greater than 10000k in the home folder

12) Login

ssh user@host	Securely connect to host as user
ssh -p port_number user@host	Securely connect to host using a specified port
ssh host	Securely connect to the system via SSH default port 22
telnet host	Connect to host via telnet default port 23

13) File Transfer

scp file1.txt server2/tmp	Securely copy file1.txt to server2 in /tmp directory
rsync -a /home/apps  /backup/	Synchronize contents in /home/apps directory with /backup  directory

14) Disk Usage

df  -h	Displays free space on mounted systems
df  -i	Displays free inodes on filesystems
fdisk  -l	Shows disk partitions, sizes, and types
du  -sh	Displays disk usage in the current directory in a human-readable format
findmnt	Displays target mount point for all filesystems
mount device-path mount-point	Mount a device

15) Directory Traverse

cd ..	Move up one level in the directory tree structure
cd	Change directory to $HOME directory
cd /test	Change directory to /test directory

 

Ansible Cheat Sheet

SSH Setup Copy your Ansible Master's public key to the managed node ssh-keygen  ## generate public key ssh-copy-id  # copy key, provide password to node configure Hosts file /etc/ansible/hosts [production] prod1.prod.local prod2.prod.local [dev] devweb1.dev.local devweb2.dev.local REMOTE CMD (Ad Hoc) Ping specific node ansible -i hosts nycweb01.prod.local -m ping Ping with wildcard ansible -i hosts "nycweb*" -m ping Ping all nodes with SSH user 'root' ansible -i hosts all -m ping -u root run a command ansible -i hosts dev -a 'uname -a' check Yum packages ansible -i hosts dev -m yum  check if Docker rpm is installed ansible -i hosts web01.nyc.local -m shell -a "rpm -qa | grep docker" Get facts about a box ansible -i hosts web01.nyc.local -m setup -a 'filter=facter_*' run command with sudo ansible -i hosts target-host -m shell -a "cat /etc/sudoers" --sudo  limit command to a certain group or server: add --limit *.nyc SERVER DIAGNOSTICS Test Connection ansible -i hosts all -m ping -u root Diagnostics manage nodes via "/etc/ansible/hosts" file Debug (debug output for playbook) - debug: var=result verbosity=2   PACKAGES AND INSTALLATION install multiple packages yum: name="{{ item }}" state=present with_items:   - http    - htop   - myapp JOBS AND PROCESS CONTROL run Ansible ad hoc with 10 parallel forks ansible -i hosts testnode1 -a "uname -a" -f 10 show human readable output add this line to ansible.cfg stdout_callback=yaml CONDITIONALS y file to n VARIABLES include global variables for all Roles sample playbook splunk/ setup_splunk_playbook.yaml roles/base /tasks/main.yaml /tasks/install.yaml search_head /tasks/configure.yaml indexer /tasks/configure.yaml some_other_role /tasks/some_task.yaml hosts config.yaml Place your vars into config.yaml cat splunk/config.yaml --- # global Splunk variables splunk_version: 7.0.0 in your playbook, include the Roles cat setup_splunk_playbook.yaml - hosts: "search_heads" become_user: root become: true gather_facts: true roles: - base - search_head in your Role, include the Global Vars inside a Task cat roles/base/tasks/main.yaml --- # install Splunk Base - name: include vars include_vars: "{{ playbook_dir }}/config.yaml" - include: install.yaml vars are accessible in tasks now, cat roles/base/tasks/install.yaml - name: echo version debug: splunk version is {{ splunk_version }} Loop through a Dict variable inside a playbook cluster:   members:     splunk01: 10.123.1.0     splunk02: 10.123.1.1     splunk03: 10.123.1.2 in the playbook, - debug: msg="{{ cluster.members.values() | map('regex_replace', '(.*)', 'https://\\1:8089') | join(',') }}" >> https://10.123,1.0:8089, https://10.123.1.1:8089, etc etc Use Inventory file variables inside a playbook cat hosts [apache] nycweb01 playbook debug: msg="IP: {{ hostvars[groups['apache'][0]]['ansible_default_ipv4']['address'] }}" debug: msg="Hostname: {{ hostvars[groups['apache'][0]]['inventory_hostname'] }}" register a List/Array to be used for later, - name: parse all hostnames in group WebServer  and get their IPs, place them in a list   command: echo {{ hostvars[item]['ansible_ssh_host'] }}"   with_items: "{{ groups['webserver'] }}"   register: ip_list - name: show the IPs   debug: msg={{ ip_list.results | map(attribute='item') | list }}" export an Environment variable - name: yum install   yum: name=somepkg state=present   environment:      SOME_VAR: abc Variables inside Inventory Hosts file cat hosts [web] nycweb01.company.local [web:vars] role="super duper web server" now get the "role" variable inside the playbook, - hosts: web   gather_facts: true   tasks:     - name: print Role var       debug: msg={{ role }} // super duper web server   MODULES service: name=httpd state=[started, stopped, restarted, reloaded] enabled=[yes,no] user: name=joe state=[present,absent] uid=1001 groups=wheel shell=/bin/bash group: name=splunk gid=6600 state=[present,absent] system=[yes/no] yum: name=apache state=[present, latest, absent, removed]   file: path=/etc/file state=[file, link, directory, hard, touch, absent] group=x owner=x recurse=yes

GALAXY install Role (Module) ansible-galaxy install geerlingguy.nginx PLAYBOOKS run playbook with sudo ansible-playbook -v config-users.yaml --sudo --sudo-user=joe --ask-sudo-pass use different Hosts file ansible-playbook -v -i /path/to/hosts run playbook but only a specific task (tag) ansible-playbook playbooks/restore_bitbucket.yaml -i hosts --tags rsync or to skip: (--skip-tags tag1, tag2) store output of a command as a variable shell: cat /etc/network | grep eth0 register: address debug: msg="address is {{ address.stdout }}" configure multiple items with one task - name: more complex items to add several users   user:     name: "{{ item.name }}"     uid: "{{ item.uid }}"     groups: "{{ item.groups }}"     state: present   with_items:      - { name: testuser1, uid: 1002, groups: "wheel, staff" }      - { name: testuser2, uid: 1003, groups: staff } get path location of current Playbook (pwd) {{ playbook_dir }} Set playbook to be verbose by default - hosts: blah  strategy: debug run playbook with verbose traceback ansible-playbook -i hosts myPlaybook.yaml -vvv run playbook on multiple Host groups - hosts: "search_head, deployer" Run playbook locally on host hosts: 127.0.0.1 connection: local Prompt for password during Playbook run # Playbook to change user password - name: pw change   hosts: target   become: true   become_user: root   vars_prompt:     - name: username       prompt: "enter username for which to change the pw"     - name: password       prompt: "enter new password"       private: yes     tasks:     - name: change pw       user: "name={{ username }} password={{ password }} update_password=always"   run playbook with "dry run" / NOOP / simulate ansible-playbook foo.yml --check Run task on different target, - name: run something on some other server   debug: msg="running stuff"   delegate_to: someserver Delegate task to a host group - name: restart web servers   service: name=memcached state=restarted   delegate_to: "{{ item }}"   with_items: "{{ groups['webservers'] }}" Get IP or facter of a remote host - name: get IP   debug: msg="{{ hostvars['nycweb01']['ansible_default_ipv4']['address'] }}" or debug: msg="{{ hostvars[item]['ansible_ssh_host'] }}" with_items: "{{ groups['webservers'] }}" synchronize file (copy file from Ansible host to target)   - synchronize:       src: "{{ playbook_dir }}/files/vscode.repo"      dest: /etc/yum.repos.d/  synchronize from server A to server B with a wildcard     - name: copy Splunk Apps       synchronize:         src: "/opt/splunk/etc/apps/{{ item }}" (server A)         dest: "/opt/splunk/etc/shcluster/apps/"  (server B)       with_items:        - item1        - item2       delegate_to: server A wget a file to a location   - get_url:       url: 'https://dl.google.com/go/go1.10.linux-amd64.tar.gz'        dest: '/tmp'       force: no  # dont download if file already exists untar tar.gz USER AND GROUP MGMT change user password for user Joe (user Fred running the cmd as sudo on the target box) # 1 install passlib  pip install passlib #2 update the pw, using a hash ansible targethost -s -m user -a "name=joe update_password=always password={{ 'MyNewPassword' | password_hash('sha512') }}" -u fred --ask-sudo-pass copy public ssh key to remote authorized_keys file - hosts: targetHost   tasks:       - name: update nessus SSH keys         become_user: root         become_method: sudo         become: true         authorized_key:            user: nessus            key: "{{ lookup('pipe','cat ../files/ssh_keys/nessus.pub') }}"            state: present FILES & DIRS delete all files and hidden files in a directory vars:   app_home: /var/opt/application tasks:   - name: clear home dir   - shell: "ls -la {{ app_home }}/"     register: files_to_delete   - file: path="{{ app_home }}/{{ item }}" state=absent     with_items: "{{ files_to_delete.stdout_lines }}" get files from node ansible node1 -s -m fetch -a "src=/etc/hosts dest=/tmp" copy file to node ansible node1 -m copy -a "src=/etc/hosts  dest=/tmp/hosts" remove all files matching a wildcard file: path={{ item }} state=absent with_fileglob: /tmp/*.rpm FACTER get all facts from a node (ad hoc) ansible -i hosts targetName -m setup -a "filter="facter_*" use fact in a playbook include fact as {{ ansible_factname }} add fact to Hosts file [group] host1 admin_user=jane host2 admin_user=jack host3  [group:vars] admin_user=john get default IPV4 address ansible_default_ipv4.address Local facts place .fact file into /etc/ansible/facts.d on target node vim /etc/ansible/facts.d/fruits.fact [fruits] sweet=banana, apple, grapes bitter=grapefruit get Local facts ansible -i hosts mrx -m setup -a "filter=ansible_local"