minecraft-server-automation

Build a minecraft container execution environment using terraform.

Main Feature

It mainly supports local provisioning.
Since it uses personal resources, it is divided into two terraform.states as below considering the cost.

keeping

Resources that do not cost much even if they are constantly running are defined as keeping resources.

scheduling

For resources that incur running costs, automatically start or stop them on daily.　　 These are defined as scheduling resources.

Other Feature

• Backup
  By customizing the entrypoint shell of the Dockerfile, it is possible to restore from the latest data from backup (S3) when starting, and automatically back up when stopping.
  Continuous backups to inexpensive object storage(AWS S3) eliminate the risk of data loss due to frequent container lifecycles.
  Those activities will be notified in own slack.

• Task definition mapped from yaml
  Improves operability by defining container environment variables in multiple yaml files　and mapping them with terraform.

• Restore
  By default restore is performed from the latest backup when the container starts (As mentioned earlier), it is also possible to restore world data from a specific recovery point via terraform variable.
  This is useful when you want to travel back in time to your precious world.

Utilities

Simple Load Test

CPU load by repeatedly hitting the yes command

yes > /dev/null &
yes > /dev/null &
yes > /dev/null &
yes > /dev/null &
yes > /dev/null &

$ jobs
[1]   実行中               yes > /dev/null &
[2]   実行中               yes > /dev/null &
[3]   実行中               yes > /dev/null &
[4]   実行中               yes > /dev/null &
[5]   実行中               yes > /dev/null &

$ kill %1 %2 %3
[1] 終了しました yes > /dev/null
[2]- 終了しました yes > /dev/null
[3]+ 終了しました yes > /dev/null

The process that consumes 500MB of memory for each press of Enter is described as follows

(load-memory.sh)
#! /bin/bash
# "--bytest 5000000" is 500MB.
echo PID=$$
echo -n "[ Enter : powerup! ] , [ Ctrl+d : stop ]"
c=0
while read byte; do
   eval a$c'=$(head --bytes 5000000 /dev/zero |cat -v)'
   c=$(($c+1))
   echo -n ">"
done
echo

Run the script as follows

chmod +x load-memory.sh
./load-memory.sh

Bulk deletion of all backup vaults

aws backup list-backup-jobs | jq -r '.BackupJobs[] | select(.BackupVaultName == "minecraft-vault" )' | jq -r '.RecoveryPointArn' | xargs -L 1 aws backup delete-recovery-point --backup-vault-name minecraft-vault --recovery-point-arn

ECS Exec実行

cl=$(aws ecs list-clusters | jq -r '.clusterArns[0]' )
prefix=`echo ${cl} | sed -E 's/.+cluster\///g' `
taskarn=$(aws ecs list-tasks --cluster ${cl} | jq -r '.taskArns[0]')
taskid=`echo ${taskarn} | sed -E 's/.+task\/.+\///g' `
CONTAINER_NAME="minecraft"

echo ${cl};     \
echo ${prefix} ; \
echo ${taskarn}; \
echo ${taskid};  \
echo ${CONTAINER_NAME};  \

aws ecs execute-command  \
 --region    ap-northeast-1 \
 --cluster   ${cl} \
 --task      ${taskarn} \
 --container ${CONTAINER_NAME}\
 --command "/bin/sh" \
 --interactive

Confirm environment variables in local

docker compose run --rm mc env