Github user pepov commented on the issue:
https://github.com/apache/nifi/pull/2905
@MikeThomsen sure! If you run the integrations tests you will have the
following images available:
```
docker images | grep nifi | grep 1.8.0-SNAPSHOT
apache/nifi
1.8.0-SNAPSHOT-dockerhub a670a54ee676 30 hours ago 1.74GB
apache/nifi
1.8.0-SNAPSHOT-dockermaven 0f1e3ae32879 30 hours ago 3GB
```
Now you run one of those, for example:
```
docker run -d --name nifi apache/nifi:1.8.0-SNAPSHOT-dockermaven
```
You can inspect the volumes it created using the following command:
```
docker inspect nifi | jq '.[].Mounts | map([.Source, .Destination])'
[
[
"/var/lib/docker/volumes/139a9e99e6542165f061923168944ca184a6340b330aec3aa20efe1f70fd22a3/_data",
"/opt/nifi/nifi-1.8.0-SNAPSHOT/conf"
],
...
```
You won't be able to access that directory from your host on a Mac for
example, but you can mount it and examine it using another docker container.
Lets mount the whole `/var/lib/docker` folder and check one of the volumes:
```
docker run -ti --rm -v /var/lib/docker:/var/lib/docker debian bash -c "ls
-al
/var/lib/docker/volumes/139a9e99e6542165f061923168944ca184a6340b330aec3aa20efe1f70fd22a3/_data"
total 88
drwxr-xr-x 3 1000 1000 4096 Jul 19 15:20 .
drwxr-xr-x 3 root root 4096 Jul 19 15:19 ..
drwxr-xr-x 2 1000 1000 4096 Jul 19 15:20 archive
-rw-rw-r-- 1 1000 1000 20135 Jun 1 14:21 authorizers.xml
-rw-rw-r-- 1 1000 1000 2326 Jun 1 14:21
bootstrap-notification-services.xml
-rw-rw-r-- 1 1000 1000 3509 Jun 1 14:21 bootstrap.conf
-rw-r--r-- 1 1000 1000 271 Jul 19 15:20 flow.xml.gz
-rw-rw-r-- 1 1000 1000 8095 Jun 1 14:21 logback.xml
-rw-rw-r-- 1 1000 1000 6449 Jun 1 14:21 login-identity-providers.xml
-rw-rw-r-- 1 1000 1000 11114 Jul 19 15:19 nifi.properties
-rw-rw-r-- 1 1000 1000 8669 Jun 1 14:21 state-management.xml
-rw-rw-r-- 1 1000 1000 1437 Jun 1 14:21 zookeeper.properties
```
You can combine this with bind mounting a volume from your host system and
you are then ready to make backups from a running or even from an already
removed container for example.
After removing the nifi container forcefully:
```
docker rm -f nifi
```
You will still be able to list the volumes and mount it to an arbitrary
container as in the previous example:
```
docker volume list
DRIVER VOLUME NAME
local
11f81374f20c3b80234f5662898ac93eb7dcea9210c9c84e70782025351d9915
local
139a9e99e6542165f061923168944ca184a6340b330aec3aa20efe1f70fd22a3
local
182188a75419e8ed029b910ac5ca73675250675eac033056e11b0e1f9b7a5b84
local
3967c839cc69c373adc78efd3d1ad1d626ad068b2c7e82c09902167f243edcd1
local
8b021167e1d5b4b58d708b9c08019a6dd5a890d27bc72535085335cda5b28fc7
local
a80d1be309ddde9d76aa405642ca036df477e3bd0670e07d5de37f5521a92bd7
local
a95d23b02768fe8858937da94b41342052722589a9cf0a609f023c147eb1ee66
local
f63966beb26225b0fe146257c0d649a9a04d94b4fc2daedb192e63ca4cf0a28f
```
---