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README.md

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-# longhorn
+# Longhorn
-We put storage on cows and move them around
+
+Longhorn is a microservice based distribution storage system.
+
+It's in experimental stage now. Comments are welcome!
+
+See [wiki](https://github.com/rancher/longhorn/wiki) for more details.
+
+# Requirements
+
+Longhorn requires one or more hosts running the following software:
+
+1. We have tested with Ubuntu 16.04. Other Linux distros, including CentOS and RancherOS, will be tested in the future.
+2. Make sure `open-iscsi` package is installed on the host. If `open-iscsi` package is installed, the `iscsiadm` executable should be available. Ubuntu Server install by default includes `open-iscsi`. Ubuntu Desktop doesn't.
+
+# Single node setup
+
+You can setup all the components required to run Longhorn on a single Linux host. In this case Longhorn will create multiple replicas for the same volume on the same host. This is therefore not a production-grade setup.
+
+You can setup Longhorn by running a single script:
+```
+git clone https://github.com/rancher/longhorn
+cd longhorn/deploy
+./longhorn-setup-single-node-env.sh
+```
+The script will setup all the components required to run Longhorn, including the etcd server, longhorn-manager, and longhorn-ui automatically.
+
+After the script completes, it produces output like this:
+```
+Longhorn is up at port 8080
+```
+Congratulation! Now you have Longhorn running on the host and can access the UI at `http://<host_ip>:8080`.
+
+#### Setup example NFS server for backupstore
+Longhorn's backup feature requires an NFS server or an S3 endpoint. You can setup a simple NFS server on the same host and use that to store backups.
+```
+# Make sure you have nfs-kernel-server package installed.
+sudo apt-get install nfs-kernel-server
+./deploy-example-nfs.sh
+```
+This NFS server won't save any data after you delete the container. It's for development and testing only.
+
+After this script completes, you will see:
+```
+Use the following URL as the Backup Target in the Longhorn UI:
+nfs://10.0.0.5:/opt/backupstore
+```
+Open Longhorn UI, go to `Setting`, fill the `Backup Target` field with the URL above, click `Save`. Now you should able to use the backup feature of Longhorn.
+
+# Test volume creation and use
+
+You can now create a persistent Longhorn volume from Docker CLI using the Longhorn volume driver and use the volume in Docker containers.
+
+Docker volume driver is `longhorn`.
+
+You can run the following on any of the Longhorn hosts:
+```
+docker volume create -d longhorn vol1
+docker run -it --volume-driver longhorn -v vol1:/vol1 ubuntu bash
+```