Error in /etc/systemd/system/kubelet.service.d (put_read) Is a directory

[cofyc]

hi,

I try to use augtool to modify /etc/systemd/system/kubelet.service.d/10-kubeadm.conf, but found an error. Here is what I did

augtool> set /files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[last()+1]/KUBELET_EXTRA_ARGS "--feature-gates=PersistentLocalVolumes=true"
augtool> print /files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[1]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[1]/KUBELET_CGROUP_DRIVER = "--cgroup-driver=cgroupfs"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[2]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[2]/KUBELET_KUBECONFIG_ARGS = "--kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[3]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[3]/KUBELET_SYSTEM_PODS_ARGS = "--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[4]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[4]/KUBELET_NETWORK_ARGS = "--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[5]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[5]/KUBELET_DNS_ARGS = "--cluster-dns=172.30.0.10 --cluster-domain=cluster.local"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[6]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[6]/KUBELET_AUTHZ_ARGS = "--authorization-mode=Webhook --client-ca-file=/etc/kubernetes/pki/ca.crt"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[7]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[7]/KUBELET_POD_INFRA_ARGS = "--pod-infra-container-image=index-dev.qiniu.io/kelibrary/pause-amd64:3.0"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[8]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[8]/KUBELET_LOG_LEVEL = "-v=7"
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[9]
/files/etc/systemd/system/kubelet.service.d/10-kubeadm.conf/Service/Environment[9]/KUBELET_EXTRA_ARGS = "--feature-gates=PersistentLocalVolumes=true"
augtool> save
error: Failed to execute command
saving failed (run 'errors' for details)
augtool> errors
...
Error in /etc/systemd/system/kubelet.service.d (put_read)
  Is a directory
...

/etc/systemd/system/kubelet.service.d/10-kubeadm.conf cannot be updated.

[raphink]

Hello,

Can you show your file before the change please?

[cofyc]

@raphink

hi, /etc/systemd/system/kubelet.service.d/10-kubeadm.conf is systemd configure file for kubelet.service. After installing kubelet, I need to change configuration in this file to configure kubelet. Previously I modify this file manually, I want to automate this process. It's ok to parse this file, and print out the tree, but I cannot save my changes.

# cat /etc/systemd/system/kubelet.service.d/10-kubeadm.conf
[Unit]
Description=kubelet: The Kubernetes Node Agent
Documentation=http://kubernetes.io/docs/

[Service]
Restart=always
StartLimitInterval=0
RestartSec=10
Environment="KUBELET_CGROUP_DRIVER=--cgroup-driver=cgroupfs"
Environment="KUBELET_KUBECONFIG_ARGS=--kubeconfig=/etc/kubernetes/kubelet.conf --require-kubeconfig=true"
Environment="KUBELET_SYSTEM_PODS_ARGS=--pod-manifest-path=/etc/kubernetes/manifests --allow-privileged=true"
Environment="KUBELET_NETWORK_ARGS=--network-plugin=cni --cni-conf-dir=/etc/cni/net.d --cni-bin-dir=/opt/cni/bin"
Environment="KUBELET_DNS_ARGS=--cluster-dns=172.30.0.10 --cluster-domain=cluster.local"
Environment="KUBELET_AUTHZ_ARGS=--authorization-mode=Webhook --client-ca-file=/etc/kubernetes/pki/ca.crt"
Environment="KUBELET_POD_INFRA_ARGS=--pod-infra-container-image=index-dev.qiniu.io/kelibrary/pause-amd64:3.0"
Environment="KUBELET_LOG_LEVEL=-v=7"
ExecStart=
ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_SYSTEM_PODS_ARGS $KUBELET_NETWORK_ARGS $KUBELET_DNS_ARGS $KUBELET_AUTHZ_ARGS $KUBELET_EXTRA_ARGS $KUBELET_POD_INFRA_ARGS $KUBELET_NODE_IP_ARGS $KUBELET_CGROUPS_DRIVER $KUBELET_LOG_LEVEL

[Install]
WantedBy=multi-user.target

Environment:

# cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=16.04
DISTRIB_CODENAME=xenial
DISTRIB_DESCRIPTION="Ubuntu 16.04.2 LTS"
# uname -a
Linux <hostname> 4.4.0-72-generic #93-Ubuntu SMP Fri Mar 31 14:07:41 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
# dpkg-query -l | grep augeas
ii  augeas-lenses                      1.4.0-0ubuntu1                     all          Set of lenses needed by libaugeas0 to parse config files
ii  augeas-tools                       1.4.0-0ubuntu1                     amd64        Augeas command line tools
ii  libaugeas0                         1.4.0-0ubuntu1                     amd64        Augeas configuration editing library and API

[lutter]

Augeas gets confused about file system paths here, and thinks /etc/systemd/system/kubelet.service.d is the file it should write. The culprit are these two lines

One way to work around this would be to change the definition of the filter to exclude *.d entries, i.e. change it to something like

let filter = incl "/lib/systemd/system/*"
           . incl "/lib/systemd/system/*/*"
           . incl "/etc/systemd/system/*"
           . incl "/etc/systemd/system/*/*"
           . incl "/etc/systemd/logind.conf"
           . incl "/etc/sysconfig/*.systemd"
           . excl "/lib/systemd/system/*.d"
           . excl "/etc/systemd/system/*.d"
           . Util.stdexcl

If that works, we'd need to figure out what other patterns usually denote directories and exclude them too (seems "*.wants" falls into the same category) and update the lens.

[lutter]

I've just put up a PR that seems to fix this issue in my testing.

[cofyc]

Thanks!