QoS with Pure Service Orchestrator v6 to keep apps from running amok

One of the great new features of PSO 6 is ability to create a storage class with a pre-defined limit on IO or bandwidth (or both). Watch the following short demo to check it out.

QoS on PSO 6

More information can be found here in the PSO 6 documentation. https://github.com/purestorage/pso-csi/blob/master/docs/csi-qos-control.md

A quick sample

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: pure-block-gold
  labels:
    kubernetes.io/cluster-service: "true"
provisioner: pure-csi
parameters:
  #TODO: choose limits
  iops_limit: "30000"
  bandwidth_limit: "10G"
  backend: block
  csi.storage.k8s.io/fstype: xfs
  createoptions: -q
allowVolumeExpansion: true

Pure Service Orchestrator 6 is now GA!

Smart Provisioning in PSO 6

Simon covers the details here:
https://blog.purestorage.com/pure-service-orchestrator-6-0/

Now if you used any of the old versions of PSO you know it can smart provision across Pure Storage arrays with a single storageClass for block and one for file. Today I am proud to share the mysterious and sometimes confusing third storageClass pure is no longer installed with PSO 6. The long story is that storage class was to support legacy systems that use the 1.0 version of our driver. There has been 2.5 years to get used to pure-block. So now with the upgrade you can make the right choice.

 jowings@asgard  ~/pso-values  k get sc
NAME         PROVISIONER   RECLAIMPOLICY   VOLUMEBINDINGMODE   ALLOWVOLUMEEXPANSION   AGE
pure-block   pure-csi      Delete          Immediate           true                   56s
pure-file    pure-csi      Delete          Immediate           true                   56s

Now you have only two obvious choices.

Webinar: Raising the Bar for Kubernetes Backup and Mobility

Coming July 14 at 12 EST or 9am PST there will be a combined Kasten and Pure webinar about Kubernetes backup and mobility. As you are working on providing the expected levels of enterprise grade backup and recovery for you k8s based applications this will be a great webinar to help you learn more about what you can use to fill those requirements. Register here:

https://www.kasten.io/webinar-raising-the-bar-for-kubernetes-backup-and-mobility

Pure-Storage-webinar

There will be a demo! Looking forward to seeing all of you there.

Use Kasten K10 to migrate K8s Volumes to Pure Storage

TL;DR – Move Kubernetes volumes from legacy storage to Pure Storage.

So you have an amazing new Pure Storage array in the datacenter or in public cloud. The Container Storage Interface doesn’t provide a built in way to migrate data between backend devices. I previously blogged about a few ways to clone and migrate data between clusters but the data has to already be located on a Pure FlashArray.

Lately, Pure has been working with a new partner Kasten. While more is yet to come. Check out this demo (just 5:30) and see just how easy it is to move PVC’s while maintaining the config of the rest of the k8s application.

Demo EBS to CBS (this could be used to migrate off other devices too)

This demo used EKS in AWS for the Kubernetes cluster.

  1. Application initially installed using a PVC for MySQL on EBS.
  2. Kasten is used to backup the entire state of the app with the PVC to S3. This target could be a FlashBlade in your datacenter.
  3. The application is restored to the same namespace but a Kasten Transform is used to convert the PVC to the “pure-block” StorageClass.
  4. Application is live and using PSO for the storage on Cloud Block Store.

Why

Like the book says, “End with why”. Ok maybe it doesn’t actually say that. Let’s answer the “why should I do this?”

First: Why move EBS to CBS
This PVC is 10GB on EBS. At this point in time it consumes about 30MB. How much does the AWS bill on the 10GB EBS volume? 10GB. On Cloud Block Store this data is reduced (compressed and deduped) and thin provisioned. How much is on the CBS? 3MB in this case. Does this make sense for 1 or 2 volumes? Nope. If your CIO has stated “move it all to the cloud!” This can be a significant savings on overall storage cost.

Second: Why move from (some other thing) to Pure?
I am biased to PSO for Kubernetes so I will start there and then give a few bullets of why Pure, but this isn’t the sales pitch blog. Pure Service Orchestrator allows you a simple single line to install and begin getting storage on demand for your container clusters. One customer says, “It just works, we kind of forget it is there.” and another commented, “I want 100GB of storage for my app, and everything else is automated for me.”

Why Pure?

  • Efficiency – Get more out of the all-flash, higher dedupe with no performance penalty does matter.
  • Availability – 6×9’s uptime measured across our customer base, not an array in a validation lab. Actual customers love us.
  • Evergreen – never. buy. the same TB/GB/MB again.

Hey, Don’t break EBS

TL;DR – EBS Volumes fail to mount when multipathd is installed on EKS worker nodes.

EKS and PSO Go Great together!

AWS Elastic Kubernetes Service is a great way to dive in with managed Kubernetes in the cloud. Pure Service Orchestrator integrates EKS worker nodes into the Cloud Block Store on AWS. I created this ansible playbook to make sure the right packages and services are started on my worker nodes.

---
- hosts: all
  become: yes
  tasks:
  - name:    Install prerequisites
    yum:     
      name: ['iscsi-initiator-utils', 'device-mapper-multipath']
      update_cache: yes
  - name:    Create directories
    file:
      path: "{{ item }}"
      state: directory
      mode: 0755
    with_items:
      - /etc/multipath
  - name: Copy file with owner and permissions
    copy:
      src: ./multipath.conf
      dest: /etc/multipath.conf
      owner: root
      group: root
      mode: '0644'
  - name: REstart iscsid
    service:
      name: iscsid
      state: restarted
  - name: REstart multipathd
    service:
      name: multipathd
      state: restarted

In my previous testing with PSO and EKS I was basically focused on using PSO only. Recently the use case of migrating from EBS to CBS has shown to be pretty valuable to our customers in the cloud. To create the demo I used an app I often use for demoing PSO. It is 2 Web server containers attached to a mySQL container with a persistent volume. Very easy. I noticed though as I was using the built in gp2 Storage Class it started behaving super odd after I installed PSO. I installed the AWS EBS CSI driver. Same thing. It could not mount volumes or snapshot them in EBS. PSO volumes on CBS worked just fine. I figure most customers don’t want me to break EBS.

After digging around the internet and random old Github issues there was no one thing seemingly having the same issue. People were having problems that had like 1 of the 4 symptoms. I decided to test when in my process it broke after I enabled the package device-mapper-multipath. So it wasn’t PSO as much as a very important pre-requisite to PSO causing the issue. What it came down to is the EBS volumes were getting grabbed by multipathd and the Storage Class didn’t know how to handle the different device names. So I had to find how to use multipathd for just the Pure volumes. The right settings in multipath.conf solved this. This is what I used as an example:

blacklist {
    device {
        vendor "*"
    }
}
blacklist_exceptions {
    device {
        vendor "PURE"
        product "*"
    }
}

I am telling multipathd to ignore everything BUT Pure. This solved my issue. So I saved this into the local directory and added the section in the ansible playbook to copy that file to each worker node in EKS.
1. Copy the ansible playbook above to a file prereqs.yaml
2. Copy the above multipath blacklist settings to multipath.conf and save to the same directory as prereqs.yaml
3. Run the ansible playbook as shown below. (make sure the inventory.ini has IP’s and you have the SSH key to login to each worker node.

# Make sure inventory.ini has the ssh IP's of each node. 
# prereqs.yaml includes the content from above

ansible-playbook -i inventory.ini -b -v prereqs.yaml -u ec2-user

This will install the packages, copy multipath.conf to /etc and restart the services to make sure they pick up the new config.

What’s new in PSO 5.1 and 5.2

This is mainly just a post to refer to the updates I shared on the main Pure Storage blog.

Check out the blog!

BTW… saw this photo from Dockercon 2017, we have come a long way with PSO. Also my beard has come a long way. Can’t believe it has been 3 years.

Dockercon April 2017

Kubernetes Topology for StatefulSet Storage Redundancy with PSO

  1. Label your hosts.
  2. Install PSO with Labels
  3. Set your StorageClass to use WaitForFirstConsumer
  4. Set the StatefulSet to schedule pods for a “nodeSelector”.

For the full “walkthrough” please see the demo content on GitHub.
https://github.com/2vcps/pso-topology-crdb

It would be great to hear how this works for you and how it can solve your Cloud Native Database requirements.

Upgrading K8s to 1.17.4 and PSO to 5.1.0

This morning I needed to upgrade one of my dev clusters to 1.17.4. I decided to capture the experience. Don’t worry I speed up the ansible output flying by

I use Kubespray to deploy and upgrade my clusters. I didn’t do anything really to prepare. All of my clusters I can rebuild pretty easy from Terraform if anything breaks.

git clone git@github.com:kubernetes-sigs/kubespray.git
cd kubespray
## Make sure you copy your actual inventory. For more information see the kubespray github repo
ansible-playbook -i inventory/dev/inventory.ini -b -v upgrade-cluster.yaml
Take some time and upgrade

Watch it go for about 40 minutes in my case. Remember this is a dev cluster and the pods I have running can restart all they want. I don’ t care. Everything upgrades through the first part of the video. Now lets upgrade Pure Service Orchestrator.

helm upgrade -n pure-csi pso pure/pure-csi -f dev-values.yaml

Done.

Now if you watch the video you will notice I had to add the Pure Storage helm repo. This was a new jump box in the lab. So I had PSO installed just not from this actual host. It is easy to add. More details are in the Pure Helm Chart README.

Migrating K8s Stateful Apps with Pure Storage

I have to move my harbor instance to a new cluster.

  1. old cluster – find all the PVC’s
kubectl -n harbor get pvc
NAME                                     STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS   AGE
data-harbor-harbor-redis-0               Bound    pvc-aebe5589-f484-4664-9326-03ff1ffb2fdf   5Gi        RWO            pure-block     24m
database-data-harbor-harbor-database-0   Bound    pvc-b506a2d4-8a65-4f17-96e3-f3ed1c25c56e   5Gi        RWO            pure-block     24m
harbor-harbor-chartmuseum                Bound    pvc-e50b2487-2a88-4032-903d-80df15483c37   100Gi      RWO            pure-block     24m
harbor-harbor-registry                   Bound    pvc-923fa069-21c8-4920-a959-13f7220f5d90   200Gi      RWO            pure-block     24m
  1. clone in the FlashArray
    Find each PVC listed when you run the above command, you may either create a snapshot or a full clone.
  2. Bring up the new app with the same sized PVC’s on your new cluster.
kubectl -n harbor scale deployment --replicas 0 -l app=harbor
  1. scale app to 0 replicas on the new k8s cluster (example above)
  2. Clone and overwrite each volume on the FlashArray. Using the pvc volume name from the new cluster.
kubectl -n get pvc

  1. Scale app back to the required replicas. Verify it works.
kuebctl -n harbor scale deployment --replicas 1 -l app=harbor
  1. Point DNS to new loadbalancer/ingress
kubectl -n harbor get ingresses
NAME                    HOSTS                                         ADDRESS         PORTS     AGE
harbor-harbor-ingress   harbor.newstack.local,notary.newstack.local   10.xx.xx.xx  80, 443   32m

Change DNS to the new cluster.

All my data is now migrated

Kubespray and vSphere VMs

I build and destroy Kubernetes clusters nearly weekly. Doing it on VMs makes this super easy. I also need to demo Pure Service Orchestrator so having in guest iSCSI is a must. Following this repo should give any vSphere admin an easy way to learn kubectl, helm and PSO quite easily (of course PSO works with Pure FlashArray and FlashBlade). This uses Terraform to create the VM and Kubespray to install k8s. Ansible can also be used for a few automations of package installs and updates.

I am going to try something new and not recreate the github readme and just share the repo link.

https://github.com/2vcps/tf4vsphere