Cloud Native – Page 16

Quick Tip - How to mount CIFS & NFS volumes on Photon OS?

01.13.2016 by William Lam // 9 Comments

I caught the following tweet from Christian this morning and thought I do a quick blog post on how to mount an external volume like a CIFS or NFS share on VMware's Photon OS.

Hm, anyone tried to get CIFS mount-points
in Photon?

— Christian Mohn™ (@h0bbel) January 12, 2016

For mounting an NFS volume, an NFS client is required and this is provided through the nfs-utils package which is not installed by default on Photon OS. To install the package, you just simply need to run the following command:

tdnf -y install nfs-utils cifs-utils

Once the nfs-utils is installed, you can mount your NFS volume by using the mount command like the following:

mount -t nfs [NFS-SERVER]:/path/to/share /mountpoint

If you want to ensure the volume is automatically mounted, you will need to add an entry to /etc/fstab. If you want more details, you can perform a quick Google search for further instructions

For mounting a CIFS or SMB volume, you need to install cifs-utils package and then specify the "cifs" mount type like the following:

mount -t cifs //[CIFS-SERVER]//path/to/share /mountpoint

If you require authentication to your CIFS or SMB volume, you just need to specify -o username=[USERNAME],password=[PASSWORD]

Lastly, I also want to mention that the instructions above is not specific to Photon OS but applies to any other *Nix platform.

How to update AppCatalyst's default PhotonOS VM template w/Docker 1.9?

12.19.2015 by William Lam // 9 Comments

For those of you using VMware's free AppCatalyst Hypervisor, you may have noticed that there is currently not a way to update to the latest Docker 1.9 Engine/Client using Photon's package manager, Tiny Dandified YUM (tndf). Although you can manually install Docker 1.9 on any deployed PhotonOS VMs from AppCatalyst, the only issue with that is that all VMs based off of the default PhotonOS template will still be running version 1.8, which means you would need to apply to do this on ever new VM creation.

Not ideal at the moment, but there is a simple fix which is to update the default PhotonOS template with Docker 1.9. We can easily this simply by leveraging AppCatalyst itself to update itself 😉 or rather its default PhotonOS VMDK. Below are the manual steps if you wish to walk through this yourself, but if you rather just run a simple script that will compeltely automate the entire process, just jump straight to the bottom of this article 🙂

Step 1 - Create a new temp PhotonOS VM (in my example, I'm calling it PHOTON-DOCKER-1.9) which we will use to install Docker 1.9. You can do so by running the following command:

/opt/vmware/appcatalyst/bin/appcatalyst vm create PHOTON-DOCKER-1.9

Step 2 - Power on the temp PhotonOS VM that you just created by running the following command:

/opt/vmware/appcatalyst/bin/appcatalyst vmpower on PHOTON-DOCKER-1.9

Step 3 - Retrieve the IP Address of the temp PhotonOS by running the following command (this could take up to a minute or so to display):

/opt/vmware/appcatalyst/bin/appcatalyst guest getip PHOTON-DOCKER-1.9

Step 4 - We can now SSH to the temp PhotonOS by using the IP Address from the previous step. You will need to specify the private key to login to the PhotonOS by running the following command:

ssh -i /opt/vmware/appcatalyst/etc/appcatalyst_insecure_key photon@[IP-ADDRESS]

Step 5 - Now we will download and install Docker 1.9 but before doing so we also need to grab the "tar" utility as it does not seem to be part of the default PhotonOS. Here is a one-liner that will automatically install the tar utility and then perform the download and install of Docker (Thanks to Massimo Re'Ferre for his original install steps, just polishing up his awesomeness). Copy and paste the snippet below which you will run that inside of the PhotonOS:

sudo tdnf -y install tar;curl -O https://get.docker.com/builds/Linux/x86_64/docker-1.9.1.tgz;tar -zxvf docker-1.9.1.tgz;sudo systemctl stop docker;sudo cp usr/local/bin/docker /usr/bin/docker;sudo systemctl start docker;rm -rf usr/;rm -f docker-1.9.1.tgz;exit

Step 6 - Now that we have our PhotonOS updated with Docker 1.9, we just need to shut it down and replace the VMDK with AppCatalyst's default PhotonOS VMDK. Run the following command to find the name of your temp PhotonOS VMDK.

find "${HOME}/Documents/AppCatalyst/PHOTON-DOCKER-1.9" -name '*.vmdk'

Once you have the VMDK name, you should backup the original AppCatalyst's PhotonOS VMDK by running the following command:

sudo mv /opt/vmware/appcatalyst/photonvm/photon-disk1-cl1.vmdk /opt/vmware/appcatalyst/photonvm/photon-disk1-cl1.vmdk.bak

Next, we will copy our temp PhotonOS VMDK to AppCatalyst's default PhotonOS directory and replace its original VMDK by running the following command:

sudo cp ${HOME}/Documents/AppCatalyst/PHOTON-DOCKER-1.9/photon-disk1-cl2.vmdk /opt/vmware/appcatalyst/photonvm/photon-disk1-cl1.vmdk

Finally, we need to make sure the new VMDK has the correct permissions by running the following command:

sudo chmod 644 /opt/vmware/appcatalyst/photonvm/photon-disk1-cl1.vmdk

Step 7 - At this point, you can verify that your changes were successful by creating a new PhotonOS VM and once logged into the VM, you can run "docker version" to verify that you are now running Docker 1.9 as shown in the screenshot below.

For those those of you who do not wish to go through the manual steps, here is a quick script called update_docker_client_in_appcatalyst.sh which automates this entire process describe in the instructions above. Here is a quick screenshot of a sample execution of the script. I am hoping the Photon team will be updating the tdnf online repo so that you can simple run yum -y update docker in the future.

Using Ansible to provision a Kubernetes Cluster on VMware Photon

11.05.2015 by William Lam // 1 Comment

I am always interested in learning and playing with new technologies, solutions and tools. Ansible, a popular configuration management tool which was recently acquired by Redhat, is one such tool that I have had on my to do list for some time now. It is quite difficult to find extra free time and with a new 7month year old, it has gotten even harder. However, in the last week or so I have been waking up randomly at 4-5am and I figured I might as well put this time to go use and give Ansible a try.

As the title suggests, I will be using Ansible to deploy a Kubernetes Cluster running on top of VMware's Photon OS. The motivation behind this little project was after watching Kelsey Hightower's recorded session at HashiConf on Managing Applications at Scale and comparing HashiCorp's Nomad and Google's Kubernetes (K8s) scheduler. I knew there were already a dozen different ways to deploy K8s, but I figure I would try something new and add a VMware spin to it by using the Photon OS.

I had found an out dated reference on setting up K8s in the Photon OS documentation and though a few of the steps are no longer needed, it provided a good base for me on creating the Ansible playbook for setting up a K8s Cluster. If you are not familiar with Ansible, this getting started guide was quite helpful. For our K8s setup, we will have a 2-Node setup, one being the Master and the other the Minion. If you are interested in an overview of K8s, be sure to check out the official documentation here.

Step 1 - You will need to deploy at least 2 Photon OS VMs, one for the Kubernetes Master and one for the Minon. This can be done using either the ISO or by deploying the pre-packaged OVA. For more details on how to setup Photon OS, please refer to the documentation here. This should take only a few minutes as the installation or deployment of Photon OS is pretty quick. In my setup, I have 192.168.1.133 as Master and 192.168.1.111 as the Minion.

Step 2 - Download and install Ansible on your client desktop. There are several options depending on the platform you plan to use. For more information take a look at the documentation here. In my setup, I will be using a Mac OS X system and you can easily install Ansible by running the following command:

brew install ansible

Step 3 - Next, to verify and test that our installation of Ansible was successful, we will need to create our inventory host file (I called it hosts but you can name it anything you want) which will contain the mappings to our Photon OS VMs. The example below assumes you do not have DNS running in your environment and I am making use of the variable options in host file to specify a friendly names versus just using the IP Addresses which will be read in later. If you do have DNS in your environment, you do not need the last section of the file.

[kubernetes_cluster]
192.168.1.133
192.168.1.111

[masters]
192.168.1.133

[minions]
192.168.1.111

[kubernetes_cluster:vars]
master_hostname=photon-master
master_ip=192.168.1.133
minion_hostname=photon-node
minion_ip=192.168.1.111

Step 3 - We will be performing a basic "ping" test to validate that Ansible is in fact working and can communicate with our deployed Photon VMs. Run the following command which will specify the inventory host file as input:

ansible -i hosts all -m ping --user root --ask-pass

Step 4 - If the previous step was successful, we can now create our Ansible playbook which will contain the instructions on setting up our K8s Cluster. Download the kubernetes_cluster.yml to your desktop and then run the following command:

ansible-playbook -i hosts --user root --ask-pass kubernetes_cluster.yml

If you want to use SSH keys for authentication and if you have already uploaded the public keys to your Photon VMs, then you can replace --ask-pass with --private-key and specify the full path to your SSH private keys.

Step 5 - Once the Ansible playbook has been successfully executed, you should see summary at the end showing everything was ok. To verify that our K8s Cluster has been properly setup, we will check the Minon's node status state which should show "ready". To do so, we will login to the K8s Master node and run the following command:

kubectl get nodes

You should see that the status field shows "Ready" which means the K8s Cluster has been properly configured.

At this point you have a basic K8s Cluster setup running on top of VMware Photon. If you are interested in exploring K8s further, there are some nice 101 and 201 official tutorials that can be found here. Another handy reference that I used for creating my Ansible playbook was this article here which provided a way to create loops using the lineinfile param.