diff --git a/docs/index.html b/docs/index.html index e8818f30..78614e90 100644 --- a/docs/index.html +++ b/docs/index.html @@ -204,7 +204,6 @@ Remember to change: details ??? ---- -- [Slack](http://lisainvite.herokuapp.com/) account +- [Slack](https://community.docker.com/registrations/groups/4316) account
(to join the conversation during the workshop) - [Docker Hub](https://hub.docker.com) account @@ -387,11 +391,15 @@ wait - If you use Play-With-Docker: - - you can't SSH to the machines + - you don't need to SSH to the machines +
(just click on the node that you want to control in the left tab bar) - - you access the terminal directly in your browser + - Play-With-Docker automagically detects exposed ports +
(and displays them as little badges with port numbers, above the terminal) - - exposing services requires something like + - You can access HTTP services by clicking on the port numbers + + - exposing TCP services requires something like [ngrok](https://ngrok.com/) or [supergrok](https://github.com/jpetazzo/orchestration-workshop#using-play-with-docker) @@ -411,7 +419,7 @@ wait - When we will use the other nodes, we will do it mostly through the Docker API -- We will use SSH only for the initial setup and a few "out of band" operations +- We will log into other nodes only for initial setup and a few "out of band" operations
(checking internal logs, debugging...) --- @@ -448,9 +456,9 @@ You are welcome to use the method that you feel the most comfortable with. ## Brand new versions! -- Engine 1.13-rc -- Compose 1.10-rc -- Machine 0.9-rc +- Engine 1.13 +- Compose 1.10 +- Machine 0.9 .exercise[ @@ -465,6 +473,24 @@ You are welcome to use the method that you feel the most comfortable with. --- +class: title + +All right! +
+We're all set. +
+Let's do this. + +--- + +name: part-1 + +class: title + +Part 1 + +--- + # Our sample application - Visit the GitHub repository with all the materials of this workshop: @@ -706,7 +732,7 @@ Tip: use `^S` and `^Q` to pause/resume log output. .exercise[ -- Open http://[yourVMaddr]:8000/ (from a browser) +- With a web browser, connect to `node1` on port 8000 ] @@ -1220,12 +1246,9 @@ ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS docker swarm join-token worker ``` -- Log into `node2`: - ```bash - ssh node2 - ``` +- Switch to `node2` -- Copy paste the `docker swarm join ...` command +- Copy-paste the `docker swarm join ...` command
(that was displayed just before) ] @@ -1235,7 +1258,7 @@ ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ## Check that the node was added correctly -- Stay logged into `node2`! +- Stay on `node2` for now! .exercise[ @@ -1263,7 +1286,7 @@ ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS .exercise[ -- Logout from `node2` (with `exit` or `Ctrl-D` or ...) +- Switch back to `node1` - View the cluster from `node1`, which is a manager: ```bash @@ -1285,13 +1308,18 @@ ehb0...4fvx node2 Ready Active - We don't have to SSH into the other nodes, we can use the Docker API -- Our nodes expose the Docker API over port 2376/tcp, -
- protected by TLS mutual authentication +- If you are using Play-With-Docker: -- To connect to other nodes with the Docker API, we will use Docker Machine + - the nodes expose the Docker API over port 2375/tcp, without authentication - (Our nodes have been suitably pre-configured to be controlled through `node1`) + - we will connect by setting the `DOCKER_HOST` environment variable + +- Otherwise: + + - the nodes expose the Docker API over port 2376/tcp, with TLS mutual authentication + + - we will use Docker Machine to set the correct environment variables +
(the nodes have been suitably pre-configured to be controlled through `node1`) --- @@ -1393,17 +1421,39 @@ You should see your 5 nodes. --- -## Adding a node through the Docker API +## Change the node targeted by the Docker CLI -- Now, let's use Docker Machine to switch to `node3` and add it to the cluster +- We need to set the right environment variables to communicate with `node3` .exercise[ -- Communicate with `node3`: +- If you're using Play-With-Docker: + ```bash + export DOCKER_HOST=tcp://node3:2375 + ``` + +- Otherwise, use Docker Machine: ```bash eval $(docker-machine env node3) ``` +] + +--- + +## Adding a node through the Docker API + +Note: it can be useful to use a [custom shell prompt]( +https://github.com/jpetazzo/orchestration-workshop/blob/master/prepare-vms/scripts/postprep.rc#L68) +reflecting the `DOCKER_HOST` variable. + +.exercise[ + +- Check which node we're talking to: + ```bash + docker info | grep ^Name + ``` + - Add `node3` to the Swarm: ```bash docker swarm join --token $TOKEN node1:2377 @@ -1411,23 +1461,34 @@ You should see your 5 nodes. ] -Note: it can be useful to use a [custom shell prompt]( -https://github.com/jpetazzo/orchestration-workshop/blob/master/prepare-vms/scripts/postprep.rc#L68) -reflecting the `DOCKER_HOST` variable. - --- -## Checking that our node is here +## Going back to the local node -- We have to go back to the local node first +- We need to revert the environment variable(s) that we had set previously .exercise[ -- Reset the environment variables: +- If you're using Play-With-Docker, just clear `DOCKER_HOST`: + ```bash + unset DOCKER_HOST + ``` + +- Otherwise, use Docker Machine to reset all the relevant variables: ```bash eval $(docker-machine env -u) ``` +] + +--- + +## Checking the composition of our cluster + +- Now that we're talking to `node1` again, we can use management commands + +.exercise[ + - Check that the node is here: ```bash docker node ls @@ -1530,19 +1591,42 @@ Some presentations from the Docker Distributed Systems Summit in Berlin: - Let's make our cluster highly available -.exercise[ +- Can you write a tiny script to automatically retrieve the manager token, +
and automatically add remaining nodes to the cluster? -- Get the manager token and use it to add nodes 4 and 5 to the cluster: - ```bash - TOKEN=$(docker swarm join-token -q manager) - for N in 4 5; do - eval $(docker-machine env node$N) - docker swarm join --token $TOKEN node1:2377 - done - eval $(docker-machine env -u) - ``` +-- -] +- Hint: we want to use `for N in $(seq 4 5) ...` + +--- + +## Adding more managers + +With Play-With-Docker: + +```bash +TOKEN=$(docker swarm join-token -q manager) +for N in $(seq 4 5); do + export DOCKER_HOST=tcp://node$N:2375 + docker swarm join --token $TOKEN node1:2377 +done +unset DOCKER_HOST +``` + +--- + +## Adding more managers + +With Docker Machine: + +```bash +TOKEN=$(docker swarm join-token -q manager) +for N in $(seq 4 5); do + eval $(docker-machine env node$N) + docker swarm join --token $TOKEN node1:2377 +done +eval $(docker-machine env -u) +``` --- @@ -1552,7 +1636,7 @@ Some presentations from the Docker Distributed Systems Summit in Berlin: - Try the following command on a few different nodes: ```bash - ssh nodeX docker node ls + docker node ls ``` ] @@ -1569,6 +1653,20 @@ As we saw earlier, you can only control the Swarm through a manager node. --- +## Play-With-Docker node status icon + +- If you're using Play-With-Docker, you get node status icons + +- Node status icons are displayed left of the node name + +- No icon = no Swarm mode detected + +- Solid blue icon = Swarm manager detected + +- Blue outline icon = Swarm worker detected + +--- + ## Promoting nodes - Instead of adding a manager node, we can also promote existing workers @@ -1692,13 +1790,9 @@ As we saw earlier, you can only control the Swarm through a manager node. .exercise[ -- Log into the node *or* use Docker Machine to talk to it: - ```bash - ssh nodeX - ``` - ```bash - eval $(docker-machine env nodeX) - ``` +- If you use Play-With-Docker, switch to that node's tab, or set `DOCKER_HOST` + +- Otherwise, `ssh` into tht node or use `$(eval docker-machine env node...)` ] @@ -1718,10 +1812,7 @@ As we saw earlier, you can only control the Swarm through a manager node. docker logs ``` -- Go back to `node1` afterwards by logging out of SSH, or by running: - ```bash - eval $(docker-machine env -u) - ``` +- Go back to `node1` afterwards ] @@ -1797,7 +1888,9 @@ The latest version of the ElasticSearch image won't start without mandatory conf - If you are fast enough, you will be able to see multiple states: - assigned (the task has been assigned to a specific node) + - preparing (right now, this mostly means "pulling the image") + - running - When a task is terminated (stopped, killed...) it cannot be restarted @@ -1847,16 +1940,73 @@ about this instance; including a randomly-generated super-hero name. ] --- +Note: if you don't have `jq` on your Play-With-Docker instance, just install it: +```bash +apk add --no-cache jq +``` + +--- + +## Load balancing results + +Traffic is handled by our clusters [TCP routing mesh]( +https://docs.docker.com/engine/swarm/ingress/). Each request is served by one of the 7 instances, in rotation. -Note: if you try this in your browser, you will probably see the same +Note: if you try to access the service from your browser, +you will probably see the same instance name over and over, because your browser (unlike curl) will try to re-use the same connection. --- +## Under the hood of the TCP routing mesh + +- Load balancing is done by IPVS + +- IPVS is a high-performance, in-kernel load balancer + +- It's been around for a long time (merged in the kernel since 2.4) + +- Each node runs a local load balancer + + (Allowing connections to be routed directly to the destination, + without extra hops) + +--- + +## Managing inbound traffic + +There are many ways to deal with inbound traffic on a Swarm cluster. + +- Put all (or a subset) of your nodes in a DNS `A` record + +- Assign your nodes (or a subet) to an ELB + +- Use a virtual IP and make sure that it is assigned to an "alive" node + +- etc. + +--- + +## Managing HTTP traffic + +- The TCP routing mesh doesn't parse HTTP headers + +- If you want to place multiple HTTP services on port 80, you need something more + +- You can setup NGINX or HAProxy on port 80 to do the virtual host switching + +- Docker Universal Control Plane provides its own [HTTP routing mesh]( + https://docs.docker.com/datacenter/ucp/2.1/guides/admin/configure/use-domain-names-to-access-services/) + + - add a specific label starting with `com.docker.ucp.mesh.http` to your services + + - labels are detected automatically and dynamically update the configuration + +--- + ## Terminate our services - Before moving on, we will remove those services @@ -2289,7 +2439,9 @@ It has been replaced by the new version, with port 80 accessible from outside. .exercise[ -- Point your browser to any node, on port 8000 +- If you're using Play-With-Docker, just click on the `(8000)` badge + +- Otherwise, point your browser to any node, on port 8000 ] @@ -2374,27 +2526,7 @@ Note: if the hash rate goes to zero and doesn't climb back up, try to `rm` and ` --- -## Checkpoint - -- We've seen how to set up a Swarm - -- We've used it to host our own registry - -- We've built our app container images - -- We've used the registry to host those images - -- We've deployed and scaled our application - -Let's treat ourselves with a nice pat on the back! - --- - -And carry on, we have much more to see and learn! - ---- - -## Interlude: making our app "Swarm-ready" +## How did we make our app "Swarm-ready"? This app was written in June 2015. (One year before Swarm mode was released.) @@ -2458,6 +2590,30 @@ https://hub.docker.com/r/jpetazzo/dockercoins_worker/tags/) --- +## Summary + +- We've seen how to set up a Swarm + +- We've used it to host our own registry + +- We've built our app container images + +- We've used the registry to host those images + +- We've deployed and scaled our application + +- Awesome job, team! + +--- + +name: part-2 + +class: title + +Part 2 + +--- + class: title # Operating the Swarm