liemle3893

Distributed Transactions and why you should avoid them

1. Modern technologies won't support it (RabbitMQ, Kafka, etc.);
2. This is a form of using Inter-Process Communication in a synchronized way and this reduces availability;
3. All participants of the distributed transaction need to be avaiable for a distributed commit, again: reduces availability.

Implementing business transactions that span multiple services is not straightforward. Distributed transactions are best avoided because of the CAP theorem. Moreover, many modern (NoSQL) databases don’t support them. The best solution is to use the Saga Pattern.

[...]

liemle3893

The repository for the assignment is public and Github does not allow the creation of private forks for public repositories.

The correct way of creating a private frok by duplicating the repo is documented here.

For this assignment the commands are:

1. Create a bare clone of the repository. (This is temporary and will be removed so just do it wherever.)

git clone --bare git@github.com:usi-systems/easytrace.git

liemle3893

Hydra

Version: v1.10.2

Create

hydra clients create   \
 --endpoint http://127.0.0.1:4445     \
 --id 111111    \
 --secret 123456    \

liemle3893

HOWTO: Clean Up Nomad Data Directory

Issue

When attempting to remove all of the data in the Nomad data directory, several directories and files are unable to be deleted. Many messages are logged to the console like:

rm: cannot remove ‘alloc/736f61b9-d7dc-cb73-0dd1-76b1b2ba032d/nomad-ui/secrets’: Device or resource busy
rm: cannot remove ‘alloc/ddcf5a78-5497-f4a4-a101-221fc4e0180b/fabio/alloc’: Device or resource busy
rm: cannot remove ‘alloc/ddcf5a78-5497-f4a4-a101-221fc4e0180b/fabio/secrets’: Device or resource busy

liemle3893

[SERVICE]
    Flush     1
    Log_Level info
    Parsers_File parsers.conf

[INPUT]
    Name tail
    # Log file will be placed at: /tmp/fluent-bit/logs/<app_name>/<file_name>.log
    Path /tmp/fluent-bit/logs/*/*.log
    Path_Key LogSource

liemle3893

job "minio" {
  datacenters = ["dc1"]
  type        = "service"
  
  group "minio1" {
    ephemeral_disk {
      size    = 10000
      sticky  = true
      migrate = false
    }

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scrape_configs:
  - job_name: 'consul_sd'
    consul_sd_configs:
      - server: '{{ env "NOMAD_IP_http"}}:8500'
        services: []
    relabel_configs:
      - source_labels: [__meta_consul_service_metadata_prometheus_enable]
        regex: true
        action: keep
      - source_labels: [__meta_consul_service_metadata_prometheus_path]

liemle3893

# Disable the Gradle daemon for Continuous Integration servers as correctness
# is usually a priority over speed in CI environments. Using a fresh
# runtime for each build is more reliable since the runtime is completely
# isolated from any previous builds.
variables:
  GRADLE_OPTS: "-Dorg.gradle.daemon=false"
  DOCKER_TLS_CERTDIR: ""

before_script:
  - export GRADLE_USER_HOME=`pwd`/.gradle

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            service {
                name = "go-demo"
                port = "http"
                address_mode = "driver"
                tags = [
                    "traefik.enable=true",
                    "traefik.http.middlewares.strip-go-demo.stripprefix.prefixes=/go-demo",
                    "traefik.http.routers.go-demo.entrypoints=http",
                    "traefik.http.routers.go-demo.rule=PathPrefix(`/go-demo`)",
                    "traefik.http.routers.go-demo.middlewares=strip-go-demo"

liemle3893

task "demo_api" {
            driver = "docker"
            config {
                image = "saboteurkid/go-demo:latest-debug"
            }
        }