Flannel and docker don't start - docker

Question

I'm trying to set up a kubernetes cluster on 2 nodes , centos 7.1 using this guide. However when I attempt to start the services on the minion like so:
for SERVICES in kube-proxy kubelet docker flanneld; do
systemctl restart $SERVICES
systemctl enable $SERVICES
systemctl status $SERVICES
done
I get the following error:
-- Logs begin at Wed 2015-12-23 13:00:41 UTC, end at Wed 2015-12-23 16:03:54 UTC. --
Dec 23 16:03:47 sc-test2 systemd[1]: docker-storage-setup.service: main process exited, code=exited, status=1/FAILURE
Dec 23 16:03:47 sc-test2 systemd[1]: Failed to start Docker Storage Setup.
-- Subject: Unit docker-storage-setup.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit docker-storage-setup.service has failed.
--
-- The result is failed.
Dec 23 16:03:47 sc-test2 systemd[1]: Unit docker-storage-setup.service entered failed state.
Dec 23 16:03:48 sc-test2 flanneld[36477]: E1223 16:03:48.187350 36477 network.go:53] Failed to retrieve network config: 100: Key not found (/atomic.io)
Dec 23 16:03:49 sc-test2 flanneld[36477]: E1223 16:03:49.189860 36477 network.go:53] Failed to retrieve network config: 100: Key not found (/atomic.io)
Dec 23 16:03:50 sc-test2 flanneld[36477]: E1223 16:03:50.192894 36477 network.go:53] Failed to retrieve network config: 100: Key not found (/atomic.io)
Dec 23 16:03:51 sc-test2 flanneld[36477]: E1223 16:03:51.194940 36477 network.go:53] Failed to retrieve network config: 100: Key not found (/atomic.io)
Dec 23 16:03:52 sc-test2 flanneld[36477]: E1223 16:03:52.197222 36477 network.go:53] Failed to retrieve network config: 100: Key not found (/atomic.io)
Dec 23 16:03:53 sc-test2 flanneld[36477]: E1223 16:03:53.199248 36477 network.go:53] Failed to retrieve network config: 100: Key not found (/atomic.io)
Dec 23 16:03:54 sc-test2 flanneld[36477]: E1223 16:03:54.201160 36477 network.go:53] Failed to retrieve network config: 100: Key not found (/atomic.io)
I'm sure I set the key on the master with :
etcdctl mk /coreos.com/network/config '{"Network":"172.17.0.0/16"}'
By far installation seems to be the hardest bit on using kubernetes :(

Answer 1

Today's christmas but I spent the whole day trying to get this to work :) This is what I did:
#1 FLANNEL
As mentioned I'd set the flannel etcd key on the master with:
etcdctl mk /coreos.com/network/config '{"Network":"172.17.0.0/16"}'
but I got this error when trying to start flannel on the minion:
Failed to retrieve network config: 100: Key not found (/atomic.io)
So I edited the /etc/sysconfig/flanneld file on the minion from:
# Flanneld configuration options
# etcd url location. Point this to the server where etcd runs
FLANNEL_ETCD="http://master:2379"
# etcd config key. This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_KEY="/coreos.com/network"
# Any additional options that you want to pass
#FLANNEL_OPTIONS=""
to:
# Flanneld configuration options
# etcd url location. Point this to the server where etcd runs
FLANNEL_ETCD="http://master:2379"
# etcd config key. This is the configuration key that flannel queries
# For address range assignment
FLANNEL_ETCD_KEY="/atomic.io/network"
# Any additional options that you want to pass
#FLANNEL_OPTIONS=""
i.e. changed the FLANNEL_ETCD key.
After this systemctl start flanneld worked.
#2 DOCKER
I didn't find a way to make the version installed as a dependency by kubernetes work so I uninstalled it and following the docker docs for Centos installed docker-engine and manually created a docker.service file for systemctl.
cd /usr/lib/systemd/system
and the contents of the docker.service:
[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network.target docker.socket
Requires=docker.socket
Requires=flanneld.service
After=flanneld.service
[Service]
EnvironmentFile=/etc/sysconfig/flanneld
ExecStart=/usr/bin/docker daemon -H fd:// --bip=${FLANNEL_SUBNET}
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
then start and enable the daemon with systemctl as well as query the status.
systemctl restart docker
systemctl enable docker
systemctl status docker