Kubernetes: How to increase ephemeral-storage


#1

Hi,

I have three master nodes with each 80 GB disk size.
Recently I ran into this problem:

Normal   Pulling              52s (x2 over 6m17s)  kubelet, 192.168.10.37  pulling image "gcr.io/kubeflow-images-public/tensorflow-serving-1.8gpu:latest"
  Warning  Evicted              8s (x5 over 4m19s)   kubelet, 192.168.10.37  The node was low on resource: ephemeral-storage.

–> "The node was low on resource: ephemeral-storage."

The storage on the executon node looks like this:

Filesystem                Size      Used Available Use% Mounted on
overlay                   7.4G      5.2G      1.8G  74% /
tmpfs                     3.9G         0      3.9G   0% /dev
tmpfs                     3.9G         0      3.9G   0% /sys/fs/cgroup
/dev/vda1                 7.4G      5.2G      1.8G  74% /opt
/dev/vda1                 7.4G      5.2G      1.8G  74% /mnt
/dev/vda1                 7.4G      5.2G      1.8G  74% /media
/dev/vda1                 7.4G      5.2G      1.8G  74% /home
none                      3.9G      1.5M      3.9G   0% /run
/dev/vda1                 7.4G      5.2G      1.8G  74% /etc/resolv.conf
/dev/vda1                 7.4G      5.2G      1.8G  74% /etc/selinux
/dev/vda1                 7.4G      5.2G      1.8G  74% /etc/logrotate.d
/dev/vda1                 7.4G      5.2G      1.8G  74% /usr/lib/modules
devtmpfs                  3.9G         0      3.9G   0% /host/dev
shm                      64.0M         0     64.0M   0% /host/dev/shm
/dev/vda1                 7.4G      5.2G      1.8G  74% /usr/lib/firmware
none                      3.9G      1.5M      3.9G   0% /var/run
/dev/vda1                 7.4G      5.2G      1.8G  74% /etc/docker
/dev/vda1                 7.4G      5.2G      1.8G  74% /usr/sbin/xtables-multi
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/log
/dev/vda1                 7.4G      5.2G      1.8G  74% /etc/hosts
/dev/vda1                 7.4G      5.2G      1.8G  74% /etc/hostname
shm                      64.0M         0     64.0M   0% /dev/shm
/dev/vda1                 7.4G      5.2G      1.8G  74% /usr/bin/system-docker-runc
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/lib/boot2docker
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/lib/docker
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/lib/kubelet
/dev/vda1                 7.4G      5.2G      1.8G  74% /usr/bin/ros
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/lib/rancher
/dev/vda1                 7.4G      5.2G      1.8G  74% /usr/bin/system-docker
/dev/vda1                 7.4G      5.2G      1.8G  74% /usr/share/ros
/dev/vda1                 7.4G      5.2G      1.8G  74% /etc/ssl/certs/ca-certificates.crt.rancher
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/lib/rancher/conf
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/lib/rancher/cache
devtmpfs                  3.9G         0      3.9G   0% /dev
shm                      64.0M         0     64.0M   0% /dev/shm
/dev/vda1                 7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/0181228584d6531d794879db05bf1b0c0184ed7a4818cf6403084c19d77ea7a0/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/655a92612d5b43207cb50607577a808065818aa4d6442441d05b6dd55cab3229/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/b0d8200c48b07df410d9f476dc60571ab855e90f4ab1eb7de1082115781b48bb/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/f36e7d814dcb59c5a9a5d15179543f1a370f196dc88269d21a68fb56555a86e4/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/842157b72f9155a86d2e4ee2547807c4a70c06320f5eb6b2ffdb00d2756a2662/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/cee5e99308a13a32ce64fdb853d2853c5805ce1eb71d0c050793ffaf8a000db9/merged
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/6ee5a7ad205bf24f1795fd9374cd4a707887ca2edd6f7e1b4a7698f51361966c/shm
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/79decf02c3a0eb6dd681c8f072f9717c15ba17fcb47d693fcfa1c392b3aef002/shm
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/acc7d374f838256762e03aea4378b73de7a38c97b07af77d62ee01135cc1377b/shm
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/46cb89b550bb1d5394fcbd66d2746f34064fb792a4a6b14d524d4f76a1710f7e/shm
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/0db3a0057c9194329fbacc4d5d94ab40eb2babe06dbb180f72ad96c8ff721632/shm
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/6c17379244983233c7516062979684589c24b661bc203e6e1d53904dd7de167f/shm
tmpfs                     3.9G     12.0K      3.9G   0% /opt/rke/var/lib/kubelet/pods/ea5b0e7d-18d6-11e9-86c9-fa163ebea4e5/volumes/kubernetes.io~secret/canal-token-gcxzd
tmpfs                     3.9G     12.0K      3.9G   0% /opt/rke/var/lib/kubelet/pods/eab6dac4-18d6-11e9-86c9-fa163ebea4e5/volumes/kubernetes.io~secret/cattle-token-lbpxh
tmpfs                     3.9G      8.0K      3.9G   0% /opt/rke/var/lib/kubelet/pods/eab6dac4-18d6-11e9-86c9-fa163ebea4e5/volumes/kubernetes.io~secret/cattle-credentials
tmpfs                     3.9G     12.0K      3.9G   0% /opt/rke/var/lib/kubelet/pods/5c672b02-18df-11e9-a246-fa163ebea4e5/volumes/kubernetes.io~secret/nginx-ingress-serviceaccount-token-vc522
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/c29dc914ee801d2b36d4d2b688e5b060be6297665187f1001f9190fc9ace009d/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/0591531eb89d598a8ef9bf49c6c21ea8250ad08489372d3ea5dbf561d44c9340/merged
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/c89f839b36e0f7317c78d806a1ffb24d43a21c472a2e8a734785528c22cce85b/shm
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/33050b02fc38091003e6a18385446f48989c8f64f9a02c64e41a8072beea817c/shm
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/a81da21f41c5c9eb2fb54ccdc187a26d5899f35933b4b701139d30f1af3860a4/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/f6d546b54d59a29526e4a9187fb75c22c194d28926fca5c9839412933c53ee9d/merged
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/7b0f9471bc66513589e79cc733ed6d69d897270902ffba5c9747b668d0f43472/shm
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/cae4765e9eb9004e1372b4b202e03a2a8d3880c918dbc27c676203eef7336080/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/81ee00944f4eb367d4dd06664a7435634916be55c1aa0329509f7a277a522909/merged
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/7888843c2e76b5c3c342a765517ec06edd92b9eab25d26655b0f5812742aa790/merged
tmpfs                     3.9G     12.0K      3.9G   0% /opt/rke/var/lib/kubelet/pods/c19a2ca3-18df-11e9-a246-fa163ebea4e5/volumes/kubernetes.io~secret/default-token-nzc2d
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/4d1c7efa3af94c1bea63021b594704db4504d4d97f5c858bdb6fe697bdefff9b/merged
shm                      64.0M         0     64.0M   0% /var/lib/docker/containers/e10b7da6d372d241bebcf838e2cf9e6d86ce29801a297a4e7278c7b7329e895d/shm
overlay                   7.4G      5.2G      1.8G  74% /var/lib/docker/overlay2/50df5234e85a2854b27aa8c7a8e483ca755803bc8bf61c25060a6c14b50a932c/merged

I already tried to prune all docker systems on all nodes and reconfirgured and restarted all.
Is it maybe connected with the fact that all the volumes have a limit of 7.4 GB?

How can I increase the ephemeral-storage therefore?

Thanks a lot :slight_smile: