Kubernetes cluster state management
ReShifter is a Kubernetes cluster state management library and tool.
You can use it on the command line for one-off tasks, as a Web app with an UI, or
in a cron job. It uses the etcd API to query and manipulate the state of
Kubernetes-related objects, supporting legacy (v2
, /registry
), modern
(v2
/v3
, /kubernetes.io
) as well as distro-specific keys such as the ones
used in the enterprise Kubernetes distro OpenShift.
There are many cases where ReShifter can be useful for you, for example:
See the Trello board for the current status of the work and roadmap items. You can also check out the design philosophy and architecture of ReShifter, if you want to learn more about why it works the way it does.
You can use ReShifter from the CLI via the rcli
binaries.
Get binary releases for Linux and macOS via the GitHub release page.
$ rcli -h
A CLI for ReShifter, supports backing up and restoring Kubernetes clusters.
Usage:
rcli [command]
Available Commands:
backup Creates a backup of a Kubernetes cluster
explore Probes an etcd endpoint
help Help about any command
restore Performs a restore of a Kubernetes cluster
stats Collects stats about Kubernetes-related keys from an etcd endpoint
version Displays the ReShifter version
...
Here's a simple usage example which assumes that you've got a Kubernetes cluster with an etcd on http://localhost:4001
running:
# back up Kubernetes cluster to Minio playground:
$ ACCESS_KEY_ID=Q3AM3UQ867SPQQA43P2F \
SECRET_ACCESS_KEY=zuf+tfteSlswRu7BJ86wekitnifILbZam1KYY3TG \
rcli backup create --endpoint http://localhost:4001 \
--remote play.minio.io:9000 \
--bucket mh9-test
# restore cluster from Minio playground, using backup ID 1498815551:
$ ACCESS_KEY_ID=Q3AM3UQ867SPQQA43P2F \
SECRET_ACCESS_KEY=zuf+tfteSlswRu7BJ86wekitnifILbZam1KYY3TG \
rcli restore --endpoint http://localhost:4001 \
--remote play.minio.io:9000 \
--bucket mh9-test \
--backupid 1498815551
OK, now that you know about the basic usage, why not learn more by checking out the CLI walkthrough? You can also have a look at the backup strategies as well as the configuration options for more ways to use the ReShifter CLI most effectively.
If you want to see the app in action, have a look at the app walkthrough.
If you want to use the ReShifter app, that is the Web UI, you need to use the Docker image since it bundles the static assets such as HTML, CSS, and JS and the Go binary. For example, to launch the ReShifter app locally, do:
$ docker run --rm -p 8080:8080 quay.io/mhausenblas/reshifter:0.3.22
If you want to use the ReShifter API, for example as a head-less service, you can simply use the binary, no other dependencies required:
$ curl -s -L https://github.com/mhausenblas/reshifter/releases/download/v0.3.22-alpha/reshifter -o reshifter
$ chmod +x reshifter
$ ./reshifter
The ReShifter HTTP API is defined in and available via Swagger: swaggerhub.com/apis/mhausenblas/reshifter/1.0.0
To install the ReShifter app on OpenShift, we use a Makefile
that creates a new project called reshifter
, launches the app from the Docker image, and finally exposes the service via a route
so that you can access the app from outside of the cluster. The following requires access to an OpenShift Origin 1.5 (or OpenShift Container Platform 3.5)
cluster and also the oc CLI tool locally installed:
$ make init
$ make build
$ make publish
To install the ReShifter app in a portable way, use kubectl
and the YAML files provided.
The following requires access to a vanilla Kubernetes 1.5 or above cluster and also the
kubectl CLI tool locally installed:
$ kubectl create -f https://raw.githubusercontent.com/mhausenblas/reshifter/master/deployments/reshifter-app.yaml
Note: the above YAML file defines both a Deployment
as well as a Service
object for ReShifter.
It does, however, not expose the ReShifter service to the outside world. If you want to access the app from outside the cluster,
you'll have to use Ingress or adapt the YAML file
yourself.
ReShifter supports different backup strategies.
ReShifter takes throughout the deployments (app, HTTP API, CLI) the following configuration parameters, supplied as environment variables. Currently all of them are optional, but may be required depending on the etcd setup in use or what you want to achieve, for example, backing up to an S3-compatible storage.
env var | meaning | set for |
---|---|---|
ACCESS_KEY_ID |
S3 access key ID | when backing up to remote S3-compatible storage |
SECRET_ACCESS_KEY |
S3 secret access key | when backing up to remote S3-compatible storage |
RS_ETCD_CLIENT_CERT |
path to etcd client cert file | when using a secure etcd |
RS_ETCD_CLIENT_KEY |
path to etcd client key file | when using a secure etcd |
RS_ETCD_CA_CERT |
path to etcd CA cert file | when using a secure etcd |
RS_BACKUP_STRATEGY |
if present, selects backup strategy | for backup |
RS_ETCD_API_VERSION |
if present, overwrites auto-discovery and forces ReShifter to use the specified etcd API version; allowed values are v2 or v3 |
for backup , restore , and stats |
Note:
ACCESS_KEY_ID
and SECRET_ACCESS_KEY
environment variables are understood as of the AWS guidelines
RS_ETCD_*
environment variables are understood as of the etcd2 security flags/etcd3 security flags
See the pages for testbed and development.