# Docker migrate to overlay2 from aufs script

Crazy that this is pretty much forced change without proper transition script
Based on https://www.sylvaincoudeville.fr/2019/12/docker-migrer-le-stockage-aufs-vers-overlay2/
NOT WORKING!!!! IF FOLLOWING THE ABOVE.. SOMEHOW THE CONTAINERS DO NOT RE-APPEAR!

The only way I found that is somewhat automated is the  the docker-compose way..
Which is still not 100% and require manual fixing of stupid errors of the docker-compose tool (mainly things that ere not interpreted right, like dates & userIds that need to manually surrounded by quotes etc)
Also I needed to add `network_mode: bridge` to the configs as I did not want a network definition for each container which seems to be the docker-compose default way

## Backup the whole crap before doing heart surgery
```
sudo systemctl stop docker
sudo cp -au /var/lib/docker /var/lib/docker.bk
sudo systemctl start docker
```

## Migrate
Export all container configs

```
cd ~
mkdir dockercontainers
sudo docker container list > dockercontainers/containers.txt
cat  dockercontainers/containers.txt

CIDS=$(docker container list -all | sed '1d' | awk '{print $1}')
for c in $CIDS; do mkdir dockercontainers/$c ; docker run --rm -v /var/run/docker.sock:/var/run/docker.sock ghcr.io/red5d/docker-autocompose $c > ~/dockercontainers/$c/docker-compose.yml ; done

# or if local (with fixes)
for c in $CIDS; do mkdir ~/dockercontainers/$c ; ~/autocompose.py $c > dockercontainers/$c/docker-compose.yml ; done

# check if there are no errors in the created files
for c in $CIDS; do cd ~/dockercontainers/$c ; echo ======== $c ======= ;docker-compose config  ; done

#Fix possible errors...

```

Store all images (I think not needed if no persistent references are used)

```
cd ~
mkdir dockersave
sudo docker images > dockersave/list.txt
cat  dockersave/list.txt

IDS=$(docker images | sed '1d' | awk '{print $3}')
for c in $IDS; do docker save -o dockersave/$c.tar $c; done
cat dockersave/list.txt | sed '1d' | grep -v "" | awk '{ print "docker tag "$3" "$1":"$2 }'>> dockersave/tag
```

## Change driver

```
sudo systemctl stop docker
sudo nano  /etc/docker/daemon.json
```
if the file is already there, add line `"storage-driver" : "overlay2" `
if the file is empty, you can go with ` echo '{ "storage-driver" : "overlay2" }' > /etc/docker/daemon.json`
`sudo systemctl start docker`

What also works is edit the file first and than just restart (so no need to stop first)
`sudo systemctl restart docker`



## Restore images

```
cd dockersave/
IDS=$(ls *.tar)
for c in $IDS; do docker load -i $c; done
```


## Restore containers

`for c in $CIDS; do cd ~/dockercontainers/$c ; docker-compose up -d --no-deps --build ; done`