Categories
Mastering Development System & Network

Docker running on a amazonlinux:2 with an apache webserver returns 503 service unavailable

Setting up a docker container containing a apache webserver running on a linux OS. I am trying to setup a docker environment where i run an apache webserver at a amazonlinux:2 OS through docker. I am able to set up everything but when i load the url on localhost it returns a “503 service unavailable”. […]

Categories
Mastering Development

docker can’t access container from localhost

I can’t access container app from my host. It is just a simple ExpressJS app I built for testing. I am running a Windows 10 Pro with Hyper-V. This is the result of docker version Client: Docker Engine – Community Version: 19.03.8 API version: 1.40 Go version: go1.12.17 Git commit: afacb8b Built: Wed Mar 11 […]

Categories
Mastering Development System & Network

After disabling swap memory for Docker container, but I can still see lots of swap used in my process, why?

I am running some pods (Solr & Zookeeper) on AWS EC2. Though k8s does not promote swap by default, I still enabled it by setting –fail-swap-on to false cause I want my system to be able to use swap. And then I found some strange behaviors on swap usage which I hope you could help […]

Categories
Development

add new postgres server in pgadmin on docker

i’m new to docker and postgres. i configured the postgres and pgadmin4 service containers and i want to create a new server in pgadmin. i get the ip of the postgres container by inspect instruction as 172.18.0.2 my postgres inspect result is as follows: [ { “Id”: “8a898f76c4ed5bc9e003c5d0be8ab67f7f7045fe1cc4c1cb82cc263136360c0a”, “Created”: “2020-02-11T22:54:11.018152083Z”, “Path”: “docker-entrypoint.sh”, “Args”: [ “postgres” […]

Categories
Development

Docker can’t access app in Host when port binding 8080

I have a docker image with a Java spring boot application which starts and run with no problem in a docker container at the port 8080 as you can see in a portion of the logs: 2020-02-24 02:09:07.906 INFO : Tomcat started on port(s): 8080 (http) with context path ‘/web-app’ 2020-02-24 02:09:07.909 INFO : Started […]

Categories
Development Docker GitHub Linux

How to I determine amount of resources that Docker host needs to be provision for a container, by inspecting a running system?

My goal is to define container definitions(“ContainerDefinitions”) with appropriate memory size needed in RAM to launch the docker container. For example, below code snippet for jenkins container gets launched in 500 MB RAM and it works fine, dont know why, “EcsTaskDefinition”: { “Type”: “AWS::ECS::TaskDefinition”, “Properties”: { “ContainerDefinitions”: [ { “Name”: “jenkins”, “Image”: “somedockeraccount/jenkins:ecs”, “Memory”: 500, […]