fluidB
/
fluidb-old
1
0
Fork 0
Code Pull Requests Activity

More tweaks to disco doc

Browse Source
master
Philip O Toole 8 years ago
parent d9ce247aa8
commit 35da53de37
1 changed files with 11 additions and 8 deletions
Show Stats Download Patch File Download Diff File

19
doc/DISCOVERY.md
Unescape Escape View File

@ -4,7 +4,7 @@ To form a rqlite cluster, the joining node must be supplied with the IP address
* First start one node and determine its IP address. * First start one node and determine its IP address.
* Let it become the leader. * Let it become the leader.
* Start the next node, passing the IP address of the first node to it. * Start the next node, passing the IP address of the first node to the second.
* Repeat this previous step, until you have a cluster of the desired size. * Repeat this previous step, until you have a cluster of the desired size.
To make all this easier, rqlite also supports _discovery_ mode. In this mode each node registers its IP address with an external service, and learns the _join_ addresses of other nodes from the same service. To make all this easier, rqlite also supports _discovery_ mode. In this mode each node registers its IP address with an external service, and learns the _join_ addresses of other nodes from the same service.
@ -14,6 +14,9 @@ To make all this easier, rqlite also supports _discovery_ mode. In this mode eac
To form a new cluster via discovery, you must first generate a unique Discovery URL (DU) for your cluster. This URL is then passed to each node on start-up, allowing the rqlite nodes to automatically connect to each other. To generate a DU using the free rqlite discovery service, hosted at `discovery.rqlite.com`, execute the following command: To form a new cluster via discovery, you must first generate a unique Discovery URL (DU) for your cluster. This URL is then passed to each node on start-up, allowing the rqlite nodes to automatically connect to each other. To generate a DU using the free rqlite discovery service, hosted at `discovery.rqlite.com`, execute the following command:
``` ```
curl -XPOST -w "\n" 'https://discovery.rqlite.com?size=3' curl -XPOST -w "\n" 'https://discovery.rqlite.com?size=3'
```
The output of this command will be something like so:
```
https://discovery.rqlite.com/204191ca-a8b4-4f03-b6b9-3f7a3a7546f8 https://discovery.rqlite.com/204191ca-a8b4-4f03-b6b9-3f7a3a7546f8
``` ```
The `size` paramters will be explained shortly. In the example above `https://discovery.rqlite.com/204191ca-a8b4-4f03-b6b9-3f7a3a7546f8` was returned by the service. The `size` paramters will be explained shortly. In the example above `https://discovery.rqlite.com/204191ca-a8b4-4f03-b6b9-3f7a3a7546f8` was returned by the service.
@ -27,22 +30,22 @@ When each node accesses the DU, the current list of nodes that have registered u
### Restricting the cluster size ### Restricting the cluster size
The `size` param allows you to restrict the number of nodes that can use the DU to join a cluster. In the example, if a fourth node attempts to register using the DU, it will be receive an error from the service. The `size` param allows you to restrict the number of nodes that can use the DU to join a cluster. In the example, if a fourth node attempts to register using the DU, it will be receive an error from the service.
### Controlling the registered IP address ### Controlling the registered join address
By default each node registers the address passed in via the `--http` option. However if you instead set `--httpadv` when starting a node, the node will instead register that address. By default each node registers the address passed in via the `--http` option. However if you instead set `--httpadv` when starting a node, the node will instead register that address.
## Limitations ## Limitations
If a node that is already part of a cluster, even a cluster of one, it will ignore any DU that is passed to it at startup. If a node that is already part of a cluster, it will ignore any DU that is passed to it at startup.
## Example ## Example
Create a DU: Create a DU:
``` ```
curl -XPOST -w "\n" 'https://discovery.rqlite.com/' $ curl -XPOST -w "\n" 'https://discovery.rqlite.com/'
https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007 https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007
``` ```
Pass the URL to 3 nodes, all of which can be started simultaneously: Pass the URL to 3 nodes, all of which can be started simultaneously via the following commands:
``` ```
rqlited --disco https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007 ~/node.1 $ rqlited --disco https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007 ~/node.1
rqlited -http localhost:4003 -raft localhost:4004 --disco https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007 ~/node.2 $ rqlited -http localhost:4003 -raft localhost:4004 --disco https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007 ~/node.2
rqlited -http localhost:4005 -raft localhost:4006 --disco https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007 ~/node.3 $ rqlited -http localhost:4005 -raft localhost:4006 --disco https://discovery.rqlite.com/b3da7185-725f-461c-b7a4-13f185bd5007 ~/node.3
``` ```
_This demonstration shows all 3 nodes running on the same host. In reality you probably wouldn't do this, and then you wouldn't need to select different -http and -raft ports for each rqlite node._ _This demonstration shows all 3 nodes running on the same host. In reality you probably wouldn't do this, and then you wouldn't need to select different -http and -raft ports for each rqlite node._

Write Preview
Loading…
Cancel
Save