apiVersion: apps/v1
kind: StatefulSet
metadata:
name: cockroachdb
spec:
serviceName: "cockroachdb"
replicas: 3
selector:
matchLabels:
app: cockroachdb
template:
metadata:
labels:
app: cockroachdb
spec:
# Init containers are run only once in the lifetime of a pod, before
# it's started up for the first time. It has to exit successfully
# before the pod's main containers are allowed to start.
# This particular init container does a DNS lookup for other pods in
# the set to help determine whether or not a cluster already exists.
# If any other pods exist, it creates a file in the cockroach-data
# directory to pass that information along to the primary container that
# has to decide what command-line flags to use when starting CockroachDB.
# This only matters when a pod's persistent volume is empty - if it has
# data from a previous execution, that data will always be used.
initContainers:
- name: bootstrap
image: cockroachdb/cockroach-k8s-init:0.1
imagePullPolicy: IfNotPresent
args:
- "-on-start=/on-start.sh"
- "-service=cockroachdb"
env:
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
volumeMounts:
- name: datadir
mountPath: "/cockroach/cockroach-data"
affinity:
podAntiAffinity:
preferredDuringSchedulingIgnoredDuringExecution:
- weight: 100
podAffinityTerm:
labelSelector:
matchExpressions:
- key: app
operator: In
values:
- cockroachdb
topologyKey: kubernetes.io/hostname
containers:
- name: cockroachdb
image: cockroachdb/cockroach:v1.0
imagePullPolicy: IfNotPresent
ports:
- containerPort: 26257
name: grpc
- containerPort: 8080
name: http
volumeMounts:
- name: datadir
mountPath: /cockroach/cockroach-data
command:
- "/bin/bash"
- "-ecx"
- |
# The use of qualified `hostname -f` is crucial:
# Other nodes aren't able to look up the unqualified hostname.
CRARGS=("start" "--logtostderr" "--insecure" "--host" "$(hostname -f)" "--http-host" "0.0.0.0")
# We only want to initialize a new cluster (by omitting the join flag)
# if we're sure that we're the first node (i.e. index 0) and that
# there aren't any other nodes running as part of the cluster that
# this is supposed to be a part of (which indicates that a cluster
# already exists and we should make sure not to create a new one).
# It's fine to run without --join on a restart if there aren't any
# other nodes.
if [ ! "$(hostname)" == "cockroachdb-0" ] || \
[ -e "/cockroach/cockroach-data/cluster_exists_marker" ]
then
# We don't join cockroachdb in order to avoid a node attempting
# to join itself, which currently doesn't work
# (https://github.com/cockroachdb/cockroach/issues/9625).
CRARGS+=("--join" "cockroachdb-0.cockroachdb,cockroachdb-1.cockroachdb,cockroachdb-2.cockroachdb")
fi
exec /cockroach/cockroach ${CRARGS[*]}
# No pre-stop hook is required, a SIGTERM plus some time is all that's
# needed for graceful shutdown of a node.
terminationGracePeriodSeconds: 60
volumes:
- name: datadir
persistentVolumeClaim:
claimName: datadir
volumeClaimTemplates:
- metadata:
name: datadir
spec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: 1Gi