Keep Learning, Keep Growing

 https://www.cloud13.ch/2025/04/18/oracle-cloud-infrastructure-2025-architect-associate-study-guide/

 1. Check major changes  https://docs.aws.amazon.com/eks/latest/userguide/kubernetes-versions-standard.html#kubernetes-1.31 2. Check deprecated APIs  https://kubernetes.io/docs/reference/using-api/deprecation-guide/#v1-31 3. https://docs.aws.amazon.com/eks/latest/userguide/managing-coredns.html 4. https://docs.aws.amazon.com/eks/latest/userguide/managing-kube-proxy.html 5. https://docs.aws.amazon.com/eks/latest/userguide/managing-vpc-cni.html 6. Amazon EBS CSI Driver for mounting volumes 7. AMI 

 In zabbix server Go to Configuration -> Actions -> Create action

 https://www.zabbix.com/download_agents ------------------- create a startup.sh /path/to/zabbix_agentd -c /path/to/conf/zabbix_agentd.conf ------------------- create shutdown.sh ps -ef|grep /path/to/zabbix_agentd |grep -v grep |awk '{print $2}'  |xargs kill -9 -------------------- zabbix_agentd.conf Include=/path/to/zabbix_agent/conf/zabbix_agentd/*.conf Timeout=10 HostnameItem=system.hostname ServerActive={10.1.2.123_zabbix_server_ip} ListenPort=10050 Server=10.1.2.123 LogFileSize=10 LogFile=/path/to/logs/zabbix_agentd.log PidFile=/path/to/zabbix_agent/zabbix_agentd.pid --------------------- /path/to/conf/zabbix_agentd/example.conf example.conf ----------- UserParameter=system.test,who|wc -l UserParameter=check_cpu,./custom_script.sh UserParameter=mysql.replication.discovery[*], mysql -h"$1" -P"$2" -sNX -e "show slave status" UserParameter=mysql.slave_status, mysql -h"$1" -P"$2" -sNX -e "show slave status" -----------...

Public ALB: -----------------------rules-------- - Inbound rules: ipv4 http tcp 80 0.0.0.0/0 ipv6 http tcp 80  ::/0 ipv4 https tcp 443 0.0.0.0/0 ipv6 https tcp 443 ::/0 - Outbound rules:  Custom TCP TCP 30000 - xxxxx      eks_cluster_security_group1 Custom TCP TCP 30000 - xxxxx      eks_cluster_security_group2 -----------------------AZ 3 different zones-------- -----------------Listeners and rules---------------- http:80   -> redirect to https://#{host}:443/#{path}?#{query} status code: HTTP_301 ------ https:443   -> Forward to target group if path pattern is /xxx/* then forward to target1 if header is zzzz then forward or redirect to target2 if 

#!/bin/bash SOURCE_DIR="/your/path/dir" DEST_DIR="/your/dest/dir" find "$SOURCE_DIR" -type f -name "*.gc.*" -mtime +30 -not -name "*.gz" -exec gzip {} \; mkdir -p "$DEST_DIR" mv "$SOURCE_DIR"/*.gz "$DEST_DIR"/ 2>/dev/null

  Amazon Linux 2023 (AL2023) introduces a new node initialization process nodeadm that uses a YAML configuration schema. If you’re using self-managed node groups or an AMI with a launch template, you’ll now need to provide additional cluster metadata explicitly when creating a new node group MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="//" --// Content-Type: application/node.eks.aws --- apiVersion: node.eks.aws/v1alpha1 kind: NodeConfig spec: cluster: name: my-cluster-name-prd apiServerEndpoint: https://D59F.xyz.ap-northest-2.eks.amazonaws.com certificateAuthority: Y2VydGlmaWNhdGVBdXRob3JpdHk= cidr: 172.10.0.0/16 kubelet: config: clusterDNS: - 172.10.0.10 flags: - --node-labels=app=my-app,environment=production --// Content-Type: text/x-shellscript; charset="us-ascii" #!/bin/bash set -o errexit set -o pipefail set -o nounset # Install additional packages yum install -y htop jq iptables-services --//--

 1. Modify the target EBS volume to increase it's size 2.  sudo pvs  --> to check the pv that needs to be resized inside the instance 3. sudo pvresize /dev/xxxxxxx  displayed in the step 2 4. sudo pvs  -> to the the new volume size 5. sudo vgs  -> to see the detailed vgs 6. sudo lvextend -L +20G /dev/vg_name/lv_name 7. df -kh  -> to check the current value before  extending 8. sudo xfs_growfs /dev/vg_name/lv_name df -h to check the current value after extending #IF YOUR filesystem is ext4, please change the xfs_growfs to another value

 We can have multiple persitent volumes to be attached to an EC2 instance Then we will group some of the volumes into a volume group After that we can create multiple logical volumes from that volume group

 sudo file -s /dev/nvme0n1 -> xfs sudo lsblk if the file system is mounted directly to the EBS volume, then we can use the command below  sudo xfs_growfs -d /your-folder-path df -hT sudo lsblk  ---------- Can not resize down the EBS volume Before making changes, please take a snapshot

------------------Sheet Workplan----------------- Date 1. Overview     Purpose:     Contents: Environment:  WorkTargets Current issues, Analysis Result, Joblist Reviewer: 2. Working Schedule:     Service impact     Checker     Supervisor:    3. Pre-backup job Backup target Backup method Backup time Remark 4. Working process and recover process 5. Emergency contact list 6. Othes ------------------Sheet Job Detail list----------------- ------------------Sheet Job process----------------- No: Prework Job Title: Setup Job Content: Details about the job Worker: The person in charge, or a group of people Start-time: End-time: Time:  System job:          Where: Servers, urls          Commands:  Checkers:  Who reviews the Job  Checking method:           Where:           Commands: Check expected:  ...

1. Prepare files and packages and plugins 2. Extract elasticsearch and install plugin       sudo bin/elasticsearch-plugin install file:///path/to/plugin.zip 3. Compress the elasticsearch after installing plugins 4. Move the compressed elasticsearch to the remote servers 5. Extract the compressed elasticsearch on the remote servers 6. Update concurrent recovery for the current cluster 7. Disable shard allocation 8. Node flush curl -X POST "localhost:9200/_flush/synced?pretty" GET /_cluster/health?pretty 9. Shutdown 10. Startup and tail logs 11. health_check node GET /_cluster/health?pretty 12. enable shard allocation host=$1 port=$2 curl -XPUT "http://YY.XX.ZZZ.YXZ:9200/_cluster/settings" -H 'Content-Type: application/json' -d '{ "transient" : { "cluster.routing.allocation.enable" : null } }' curl -XPUT "http://YY.XX.ZZZ.YXZ:9200/_cluster/settings" -H 'Content-Type: application/json' -d '{ ...

  POST /_cluster/reroute {    "commands": [    {       "move": {          "index": "my_index",          "shard": 0,          "from_node":  "node1",          "to_node": "node2"        }    }   ]  } { "commands": [ { "move": { "index": "my_index", "shard": 0, "from_node": "node1", "to_node": "node2" } } ] }

 https://linuxhandbook.com/awk-command-tutorial/

 (base) nhbo@nhbo-LOQ-15IAX9:~$ kubectl port-forward svc/argocd-server -n argocd 8080:443 error: error upgrading connection: error dialing backend: tls: failed to verify certificate: x509: certificate is valid for 192.168.1.5, 2402:800:61c2:10de:d38d:2b9f:6969:e8e8, 2402:800:61c2:10de:73a5:a67f:7a26:b577, not 192.168.1.7 (base) nhbo@nhbo-LOQ-15IAX9:~$ sudo microk8s refresh-certs --cert ca.crt

 We must install docker in the worker node --------- helm install arc     --namespace "${NAMESPACE}"     --create-namespace     oci://ghcr.io/actions/actions-runner-controller-charts/gha-runner-scale-set-controller ------- helm install "${INSTALLATION_NAME}"     --namespace "${NAMESPACE}"     --create-namespace     --set githubConfigUrl="${GITHUB_CONFIG_URL}"     --set githubConfigSecret.github_token="${GITHUB_PAT}"   --set containerMode.type="dind"  oci://ghcr.io/actions/actions-runner-controller-charts/gha-runner-scale-set --set containerMode.type="dind" : This will allow the container to use the docker in the host