SFTP – Connections and File Permissions – Part 1

We did SSH setup as mentioned in SSH setup – Key based authentication In this article lets talk about "umask" and file permissions while doing SFTP. When a "user" is created - default "umask" is 0002(---w) - meaning no write permission for others. When the "user" creates a file : the default file permission subtract … Continue reading SFTP – Connections and File Permissions – Part 1


AWS – Attach/Replace IAM role of running instance

https://aws.amazon.com/blogs/security/easily-replace-or-attach-an-iam-role-to-an-existing-ec2-instance-by-using-the-ec2-console/ https://aws.amazon.com/blogs/security/new-attach-an-aws-iam-role-to-an-existing-amazon-ec2-instance-by-using-the-aws-cli/ From the above articles from AWS we can now attach/replace IAM role of running instances. The below example is simple scenario to test the same using CF.. Provision EC2 Instance, Create S3 bucket, Create S3 Bucket Policy, Role and Instance Profile. But I am not attaching the instance profile to the EC2 Instance … Continue reading AWS – Attach/Replace IAM role of running instance

Docker Swarm – Manager Nodes

Reference: https://docs.docker.com/engine/swarm/swarm-tutorial/ On the manager node (to be) initialize the docker swarm cluster - "docker swarm init". It also prints the command to run on the worker node to join the cluster. If we lose the command then run "docker swarm join-token worker" on the manager node to get it and run on the nodes to … Continue reading Docker Swarm – Manager Nodes

Docker Swarm – Start Stop Node Container

In my previous blog Docker Swarm – Beginning I've started a service called "web" in global mode which runs a single instance of container on all nodes in the swarm. Now lets try to stop container/node and check the behavior. Stop container - As you can see in the below screenshot stopping a container quickly … Continue reading Docker Swarm – Start Stop Node Container

Docker Swarm – Beginning

There is already good documentation from Docker on swarm - https://docs.docker.com/engine/swarm/ In simple terms - Docker swarm is an orchestration tool to manage docker containers running on nodes ( physical or virtual servers ). We mark nodes as two types - Manager node and worker node. Manager node which does cluster management and hand over the … Continue reading Docker Swarm – Beginning

Jenkins – AWS – Ansible – Rolling Update of AMI – Part 2

As we have configured Job1 - AMI lets move to Job2 - UpdateCF. The temporary file with the AMI Id should be injected in to Job2 so that it can update cloud formation stack with the new image. Now as we are going to use ansible I've placed the code in GitHub Repo. Now in … Continue reading Jenkins – AWS – Ansible – Rolling Update of AMI – Part 2