Increasing disk space for Agents/Worker nodes in Azure Container Service

Question

I have been working with Azure Container Service and have been able to successfully create a ACS cluster which uses Kubernetes orchestratration. I have also created another ACS cluster which uses Docker-Swarm orchestration.

My question is related to the OS disks of the agent VM that are created by ACS. By Default, all the OS disks have 30GB and it seems all the container images and containers are stored on the OS disks. I hit the 30 GB limit with about 15 containers and about 10-15 images. Am I doing something wrong here?

I can create VMs with more disk space but it appears that the disk is another mount. Should I be making some change to allow the orchestration engine and docker to use the non-default drive? If so, any help on this would be appreciated.

In parallel, I did setup a Ubuntu VM and again by default the OS drive had 30 GB and the secondary had 100 GB. I changed docker-engine to use the secondary drive mount for storing the containers and images. This off course involved me SSHing into the machine and changing some docker settings. I don't presume we should be doing a similar thing on ACS as its a PaaS offering?

Answer 1

You could increase Kubernetes agent OS disk. Kubernetes agent as Azure VM as agents. More information about this please refer to this link: Azure VM supports increase OS disk. Please refer to the following steps.

1.Stop your k8s agent VM. You could do it on Azure Portal.

2.Increase OS disk size. <agent VM>--><Disks>--><OS Disk>

3.Start your k8s agent VM.

4.ssh to agent VM and check.

shui@k8s-agent-431B3739-0:~$ df -h

Filesystem      Size  Used Avail Use% Mounted on
udev            1.7G     0  1.7G   0% /dev
tmpfs           344M  5.2M  339M   2% /run
/dev/sda1        97G  2.8G   95G   3% /

But Docker-Swarm orchestration use Azure VMSS as agents. For now, VMSS does not support resize OS disk size, you could add new disks on them, please refer to this link.